Datasheet

DS_FT312D USB ANDROID HOST IC

Version 1.3

Document No.: FT_000816 Clearance No.: FTDI# 331

Future Technology
Devices International
Ltd.
DS_FT312D
(USB Android Host IC)
The FT312D is a USB 2.0 Full Speed host IC
specifically targeted at providing access to
peripheral hardware from an Android platform with
a USB device port. The device will bridge the USB
port to a UART interface via the Android Open
Accessory protocol and has the following advanced
features:
• Single chip USB to UART interface.
• 12 MHz oscillator using external crystal.
• Entire USB protocol handled on the chip. No
• Integrated power-on-reset circuit.
USB specific firmware programming required.
• +3V3Single Supply Operation with 5V tolerant
• Supports USB bulk transfer mode
inputs.
• Basic UART interface with RXD, TXD, RTS#,
• USB 2.0 Full Speed compatible.
CTS# pins.
• Extended operating temperature range; -40⁰C
• TX_ACTIVE signal for controlling transceivers
to 85⁰C.
on RS485 interfaces.
• Available in compact Pb-free 32 Pin LQFP and
• UART RX buffer size is 5512 bytes
QFN packages (both RoHS compliant).
• UART TX buffer size is 256 bytes
• USB_ERROR indicator pin
• Suitable for use on any Android platform
supporting Android Open Accessory Mode
(Typically 3.1 onwards, however some
platforms may port Open Accessory Mode to
version 2.3.4)

Neither the whole nor any part of the information contained in, or the product described in this manual, may be adapted, or reproduced
in any material or electronic form without the prior written consent of the copyright holder. This product and its documentat ion are
supplied on an as-is basis and no warranty as to their suitability for any particular purpose is either made or implied. Future Technology
Devices International Ltd will not accept any claim for damages howsoever arising as a result of use or failure of this product. Your
statutory rights are not affected. This product or any variant of it is not intended for use in any medical appliance, device, or system in
which the failure of the product might reasonably be expected to result in personal injury. This document provides preliminar y
information that may be subject to change without notice. No freedom to use patents or other intellectual property rights is implied by
the publication of this document. Future Technology Devices International Ltd, Unit 1, 2 Seaward Place, Centurion Business Park,
Glasgow, G41 1HH, United Kingdom.

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DS_FT312D USB ANDROID HOST IC
Version 1.3

Document No.: FT_000816 Clearance No.: FTDI# 331

1 Typical Applications
• Connecting Android phones to USB accessories • Home automation via Android devices
• Connecting Android tablets to USB accessories • Data logging from USB accessories
• Controlling instrumentation from Android • Connecting serial printing devices to Android
devices. devices

1.1 Part Numbers

Part Number Package
FT312D-32Q1C-x 32 Pin QFN
FT312D-32L1C-x 32 Pin LQFP

Note: Packing codes for x is:

- R: Taped and Reel, QFN 3,000pcs per reel, LQFP 1500 pcs per reel.
- (no suffix): Tray packing, 260pcs per tray QFN, 250 pcs per tray LQFP

For example: FT312D-32Q1C-R is 3,000pcs QFN taped and reel packing

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DS_FT312D USB ANDROID HOST IC
Version 1.3

Document No.: FT_000816 Clearance No.: FTDI# 331

2 FT312D Block Diagram

USB_ERROR#
TXD

RXD
USBDP
USB
RTS#
USB Host Buffer UART
USBDM Transceiver
CTS#

TX_ACTIVE

Figure 2.1 FT312D Block Diagram

For a description of the function please refer to Section 4.

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Table of Contents

1 Typical Applications ...................................................... 2

1.1 Part Numbers ............................................................................ 2
2 FT312D Block Diagram.................................................. 3
3 Device Pin Out and Signal Description .......................... 6
3.1 Package Symbol ........................................................................ 6
3.1.1 Package Pin Out Description ........................................................................... 6

4 Function Description ..................................................... 8

4.1 Key Features ............................................................................. 8
4.2 Functional Block Descriptions ................................................... 8
4.2.1 UART Interface Module .................................................................................. 8
4.2.2 Buffers ........................................................................................................ 8
4.2.3 USB Host ..................................................................................................... 8
4.2.4 USB Transceivers .......................................................................................... 8

4.3 Default Descriptor Strings......................................................... 8

5 UART Interface ........................................................... 10
6 USB Error Detection .................................................... 12
7 Absolute Maximum Ratings......................................... 13
7.1 DC Characteristics ................................................................... 13
7.2 ESD and Latch-up Specifications ............................................. 14
8 Application Examples .................................................. 15
8.1 USB to UART Converter ........................................................... 15
8.2 USB to RS232 Converter ......................................................... 16
9 Package Parameters ................................................... 17
9.1 FT312D Package Markings ...................................................... 17
9.1.1 QFN-32 ..................................................................................................... 17
9.1.2 LQFP-32 .................................................................................................... 18

9.2 FT312D Package Dimensions .................................................. 19

9.2.1 QFN-32 Package Dimensions ........................................................................ 19
9.2.2 LQFP-32 Package Dimensions ....................................................................... 20

9.3 Solder Reflow Profile .............................................................. 20

10 Contact Information ................................................... 22
Appendix A – References ................................................... 23
Document References ...................................................................... 23

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Useful utilities and examples firmware ............................................ 23

Appendix B - List of Figures and Tables ............................. 24
List of Figures .................................................................................. 24
List of Tables.................................................................................... 24
Appendix C - Revision History ............................................ 25

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3 Device Pin Out and Signal Description

3.1 Package Symbol

16

15

14

13

12

11

10

9
NC
VCCIO

RESET#
TEST0

TEST2
GND
GND
GND
17 8
USBDP TEST1
18 7
USBDM VREGOUT
19 6
GND GND
20 5
NC FT312D XTOUT
21 4
NC QFN 32 XTIN
22 3
VCCIO AVCC

USB_ERROR#
23 2
TXD VCC
TX_ACTIVE

24 1
RXD GND
VCCIO
RTS#
CTS#
GND

GND
NC
NC
25

26

27

28

29

30

31

32

33

Figure 3.1QFN Schematic Symbol

Note 1: The pinout is the same for the QFN and LQFP packages.

Note 2: Pin 33 on the symbol is the copper pad in the centre of the QFN package

3.1.1 Package Pin Out Description

Note: # denotes an active low signal.

Pin No. Name Type Description

POWER
2 VCC 3V3 supply to IC internal 1V8 regulator
Input
POWER
3 AVCC 1V8 supply to IC core
Input
POWER
13, 22, 28 VCCIO 3V3 supply for the IO cells
Input
POWER
7 VREGOUT 1V8 output. May be used as input source for pin 3.
Output
POWER
1,6,14,15,16,19,27 GND 0V Ground input.
Input
Table 3.1 Power and Ground

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Pin No. Name Type Description

Input to 12 MHz Oscillator Cell. Connect 12 MHz crystal
4 XTIN INPUT
across pins 4 and 5.
Output from 12 MHz Oscillator Cell. Connect 12 MHz
5 XTOUT OUTPUT
crystal across pins 4 and 5.
8 TEST1 INPUT For internal use. Pull to GND
9 TEST2 INPUT For factory use. Pull to 3V3.
10 RESET# INPUT Reset input (active low).
11 TEST0 OUTPUT Leave unterminated.
12 NC - No connect pins. Leave unterminated.
17 USBDP INPUT/OUTPUT USB Data Signal Plus.
18 USBDM INPUT/OUTPUT USB Data Signal Minus.
20 NC - No connect pins. Leave unterminated.
21 NC - No connect pins. Leave unterminated.
23 TXD OUTPUT Transmit asynchronous data output
24 RXD INPUT Receive asynchronous data input
25 RTS# OUTPUT Request to send control output
26 CTS# INPUT Clear to send control input
29 TX_ACTIVE OUTPUT UART active signal (typically used with RS485)
30 NC - No connect pins. Leave un-terminated
31 NC - No connect pins. Leave un-terminated
Output signal to indicate a problem with the USB
32 USB_ERROR# OUTPUT
connection
Table 3.2 Function Pins

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4 Function Description
The FT312D is FTDI’s second dedicated Android Open Accessory Mode integrated circuit device or Android
Host. The FT312D USB host port is dedicated to support of the Android Open Accessory class and will
bridge data between this port and the UART interface.

4.1 Key Features

Easy to use Android Open Accessory IC translating the Device port of the Android device into UART
capabilities.

4.2 Functional Block Descriptions

The following paragraphs describe each function within FT312D. Please refer to the block diagram shown
in Figure 2.1.

4.2.1 UART Interface Module

The FT312DUART module controls the UART interface providing basic RXD, TXD signalling with
RTS#/CTS# hardware flow control. An additional TX_Active signal is supplied to control external RS485
transceivers for users wishing to create a USB to RS485 bridge. The UART supports baud rates from 300
baud to 921600 baud. A full description of the UART module is provided in Section 5.

4.2.2 Buffers
The FT312D provides internal buffering between the USB port and the UART port of the IC for smooth
data streaming.

The Android device can send NAK’s to the USB OUT token sent from the FT312D. This can happen when
the UART application on the Android is running in the background or multiple applications are launched in
the Android device. When the UART application on the Android device is not accepting data, the data will
be buffered in the UART RX buffer in FT312D. The UART RX buffer size is 5512 bytes.

The UART_TX buffer which stores data from the USB port, heading for the UART is 256 bytes.

4.2.3 USB Host

The USB Host block handles the parallel-to-serial and serial-to-parallel conversion of the USB physical
layer. This includes bit stuffing, CRC generation.

4.2.4 USB Transceivers

USB transceiver cells provide the physical USB device interface supporting USB 1.1 and USB 2.0
standards. Low-speed and full-speed USB data rates are supported. The output driver provides 3V3 level
slew rate control signalling, whilst a differential receiver and two single ended receivers provide USB
DATA IN, SE0 and USB Reset condition detection. These cells also include integrated internal pull-down
resistors as required for host mode.

4.3 Default Descriptor Strings

When the USB port is connected to the Android USB port, the Android platform will determine which
application to load based on the strings read from the FT312D. These strings are configurable with a
Windows utility: FT312D Configuration available for download from the FTDI website. Please refer to the
application note AN_236 User Guide for FT312D Configuration Utility to change the default string values.

Default values for the strings are set in the device as per Table 4.1.

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Descriptor String Default Value

Manufacturer FTDI
Model Android Accessory FT312D
Version 1.0
Serial FTDI FT312D
Description FTDI Android Accessory FT312D
Table 4.1 Default Descriptor Strings

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5 UART Interface
The interface implements a standard asynchronous serial UART port with flow control, for example
RS232/422/485. The UART can support baud rates from 300 to 921600 with RTS/CTS flow control. The
UART can support baud rates from 300 to 115200 with no flow control.

Data transfer uses NRZ (Non-Return to Zero) data format consisting of 1 start bit, 7 or 8 data bits, an
optional parity bit, and one or two stop bits. When transmitting the data bits, the least significant bit is
transmitted first. Transmit and receive waveforms are illustrated in Figure 5-1 and Figure 5-2.

Figure 5-1 UART Receive Waveform

Figure 5-2 UART Transmit Waveform

Baud rate (default =9600 baud), flow control settings (default = None), number of data bits (default=8),
parity (default is no parity) and number of stop bits (default=1) are all configurable from the Android
application. Please refer to FT31XD Android Programmers Guide for further details.

TX_ACTIVE is transmit enable, this output may be used in RS485 designs to enable the line driver for
transmit mode.

UART RX buffer size is 5512 bytes and UART TX buffer size is 256 bytes.

Note: UART software flow control with XON/XOFF is not supported

UART hardware flow control with DTR/DSR is not supported

Note:

The FT312D has to enumerate the Android device before receiving data from the UART device.

This can be implemented by disconnecting the UART TXD signal of external UART device connected to the

FT312D RXD signal until after the FT312D has established the USB link with Android device.

The connection sequence should be:

1. Connect FT312D to Android and complete enumeration.

2. Connect the TXD of UART device to FT312D’s RXD then start to receive data.

There are two methods to implement this function:

1. When FT312D connects to the Android device and enumeration is completed, the USB_ERROR# will
become Logic 0 (default Logic 1). This signal can be used to control the TTL gate (74LVC2G241,
74LVC1G125 or others) ON/OFF such that the TXD/RXD lines are connected/disconnected.

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Figure 5-3 UART RXD and TXD connection gated by Enumeration

If the UART device has an enable pin (active high enable) such as on the GPS module, the USB_ERROR#
can also be used. The USB_ERROR# pin may be inverted with an NPN BJT then connected to the enable
pin of the GPS module.

Figure 5-4 Inverting Gate Control signal to enable GPS module (active high enable)

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6 USB Error Detection

Pin 32 of the device is provided to indicate a problem has occurred with the USB connection. The errors
are USB device not supported, USB hub not supported and USB device not responding. USB device not
supported would occur if the USB port was connected to a non-Android class device port. E.g. The
FT312D is not designed to host memory sticks or printers etc. USB hub not supported would be reported
if FT312D is connected to a USB hub. USB device not responding would occur if the USB device connected
to the FT312D host port did not respond and the enumeration failed. The signal states are as follows:

Pin state Definition

Logic 0 Device connected to USB and functional
Logic 1 Device not connected
One 100 ms logic 0 pulse Device not responding. This pulse occurs at plug-in
and then the signal returns to logic 1. This then
repeats every two seconds.
Two 100 ms logic 0 pulses Device not supported. These pulses occur at plug-
in and then the signal returns to logic 1. This then
repeats every two seconds.
Three 100 ms logic 0 pulses Hub not supported. These pulses occur at plug-in
and then the signal returns to logic 1. This then
repeats every two seconds.
Table 6.1 Error Detection

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7 Absolute Maximum Ratings

The absolute maximum ratings for FT312D are shown in Table 7.1. These are in accordance with the
Absolute Maximum Rating System (IEC 60134). Exceeding these may cause permanent damage to the
device.

Parameter Value Unit

Storage Temperature -65°C to 150°C °C
168 Hours
Floor Life (Out of Bag) At Factory Ambient
(IPC/JEDEC J-STD-033A MSL Level 3 Hours
( 30°C / 60% Relative Humidity)
Compliant)*
Ambient Temperature (Power Applied) -40°C to 85°C °C
MTTF 9,110,463 Hours
Vcc Supply Voltage 0 to +3.63 V
VCCIO 0 to +3.63 V
AVCC 0 to + 1.98 V
DC Input Voltage - USBDP and USBDM -0.5 to +(Vcc +0.5) V
DC Input Voltage - High Impedance
-0.5 to +5.00 V
Bidirectional
DC Input Voltage - All other Inputs -0.5 to +(Vcc +0.5) V
DC Output Current - Outputs 4 mA
DC Output Current - Low Impedance
4 mA
Bidirectional
Table 7.1 Absolute Maximum Ratings

* If devices are stored out of the packaging beyond this time limit the devices should be baked before
use. The devices should be ramped up to a temperature of 125°C and baked for up to 17 hours.

7.1 DC Characteristics
DC Characteristics (Ambient Temperature -40˚C to +125˚C)

Parameter Description Minimum Typical Maximum Units Conditions

VCC Operating Supply
Vcc1 2.97 3.3 3.63 V
Voltage
VCCIO Operating
Vcc2 2.97 3.3 3.63 V
Supply Voltage
VCC_PLL Operating
AVCC 1.62 1.8 1.98 V
Supply Voltage
Operating Supply
Normal
Icc1 Current 25 mA
Operation
48 MHz
Operating Supply
Icc2 128 µA USB Suspend
Current
Table 7.2 Operating Voltage and Current

Parameter Description Minimum Typical Maximum Units Conditions

I source = 8
Voh Output Voltage High 2.4 V
mA
I sink = 8
Vol Output Voltage Low 0.4 V
mA
Input Switching
Vin 1.5 V
Threshold
Table 7.3 I/O Pin Characteristics

Parameter Description Minimum Typical Maximum Units Conditions

I/O Pins Static Output
UVoh 2.8 V
( High)
I/O Pins Static Output
UVol 0.3 V
( Low )
UVse Single Ended Rx 0.8 2.0 V

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Parameter Description Minimum Typical Maximum Units Conditions

Threshold
Differential Common
UCom 0.8 2.5 V
Mode
Differential Input
UVdif 0.2 V
Sensitivity
Driver Output
UDrvZ 3 6 9 Ω
Impedance
Table 7.4 USB I/O Pin (USBDP, USBDM) Characteristics

Parameter Description Minimum Typical Maximum Units Conditions

Power supply of
1.8V power
VCCK internal core cells and 1.62 1.8 1.98 V
supply
I/O to core interface
Power supply of 1.8V 1.8V power
VCC18IO 1.62 1.8 1.98 V
OSC pad supply
Operating junction
TJ -40 25 125 °C
temperature
Iin= VCC18IO
Iin Input leakage current -10 ±1 10 µA
or 0V
Tri-state output
Ioz -10 ±1 10 µA
leakage current
Table 7.5 Crystal Oscillator 1.8 Volts DC Characteristics

7.2 ESD and Latch-up Specifications

Description Specification
Human Body Mode (HBM) ± 2000V
Machine mode (MM) ± 200V
Charged Device Mode (CDM) ± 500V
Latch-up > ± 200mA
Table 7.6 ESD and Latch-up Specifications

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8 Application Examples
The following sections illustrate possible applications of the FT312D.

8.1 USB to UART Converter

5V 3V3 3V3
REGULATOR

5V Power to USB

Ferrite VCC
Bead
VCCIO
1 UART_TXD
RESET# TXD
2 27R
USBDM
UART_RXD
3 RXD
USBDP
4 27R UART_RTS# MCU/FPGA
RTS#

5
UART_CTS#
47pF 47pF CTS#
SHIELD
FT312D UART_TX_ACTIVE
100nF TX_ACTIVE
GND

GND

AVCC LED
620R
3V3
USB_ERROR
VREGOUT
D
GN

3V3

100nF + 4.7uF 100nF

GND

GND

Figure 8.1 Application Example showing USB to UART Converter

The UART signals are at 3V3 level and may be used to drive directly into a FPGA or MCU with a 3V3
interface, or could be level shifted with an RS232, RS422 or RS485 transceiver. The TX_ACTIVE signal is
used mostly with RS485 transceivers to enable the Transmit line drivers.

The unused pins may be left unterminated.

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8.2 USB to RS232 Converter

5V 3V3 3V3
REGULATOR

5V Power to USB

Ferrite VCC
Bead
VCCIO TXD
DB9
1 UART_TXD 3
RESET# TXD
2 27R
USBDM RXD
UART_RXD 2
3 RXD
USBDP
4 27R RS232 RTS
UART_RTS#
RTS# LEVEL 7
CONVERTER
5 CTS
UART_CTS# 8
47pF 47pF CTS#
SHIELD 10
FT312D
5
100nF TX_ACTIVE
GND
SHIELD

GND

AVCC LED
620R
3V3
USB_ERROR
VREGOUT
D
GN

3V3

100nF + 4.7uF 100nF

GND

GND

Figure 8.2 Application Example showing USB to RS232 Converter

An example of using the FT312D as a USB to RS232 converter is illustrated in Figure 8.2. In this
application, a TTL to RS232 Level Converter IC is used on the serial UART interface of the FT312D to
convert the TTL levels of the FT312D to RS232 levels. This level shift can be done using line drivers from
a variety of vendors e.g., Zywyn.

A suitable level shifting device is the Zywyn ZT3243F which is capable of RS232 communication at up to
1000k baud.

The unused pins may be left unterminated.

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9 Package Parameters
FT312D is available in RoHS Compliant packages, QFN package (32QFN) and an LQFP package (32LQFP).
The packages are lead (Pb) free and use a ‘green’ compound. The package is fully compliant with
European Union directive 2002/95/EC.

The mechanical drawings of the packages are shown in Sections 9.2 - all dimensions are in millimetres.

The solder reflow profile for all packages can be viewed in Section 9.3.

9.1 FT312D Package Markings

9.1.1 QFN-32
An example of the markings on the QFN package are shown in Figure 9-1. The FTDI part number is too
long for the 32 QFN package so in this case the last two digits are wrapped down onto the date code line.

FTDI Line 1 – FTDI Logo

I
XXXXXXXX Line 2 – Wafer Lot Number

FT312D-32Q Line 3 – FTDI Part Number

1C YYWW Line 4 – Revision and Date

Code
32
1

Figure 9-1QFN Package Markings

1C should be printed on line 4, then a space and then the Date Code.

1. YYWW = Date Code, where YY is year and WW is week number

2. Marking alignment should be centre justified
3. Laser Marking should be used
4. All marking dimensions should be marked proportionally. Marking font should be using Unisem
standard font (Roman Simplex)

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9.1.2 LQFP-32
An example of the markings on the LQFP package are shown in Figure 9-2.

FTD Line 1 – FTDI Logo

I
XXXXXXXXXX Line 2 – Wafer Lot Number

FT312D-32L Line 3 – FTDI Part Number

32
1C YYWW Line 4 – Revision, Date Code

Figure 9-2 LQFP Package Markings

Notes:

1. YYWW = Date Code, where YY is year and WW is week number

2. Marking alignment should be centre justified
3. Laser Marking should be used
4. All marking dimensions should be marked proportionally. Marking font should be using Unisem
standard font (Roman Simplex)

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9.2 FT312D Package Dimensions

9.2.1 QFN-32 Package Dimensions

Figure 9-3 QFN-32 Package Dimensions

Note 1: Dimensions are in mm

Note 2: The centre pad should be connected to the GND plane for improved thermal conduction and
noise immunity.

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9.2.2 LQFP-32 Package Dimensions

Figure 9-4 LQFP-32 Package Dimensions

Note: Dimensions are in mm

9.3 Solder Reflow Profile

Figure 9-5 All packages Reflow Solder Profile

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Pb Free Solder SnPb Eutectic and Pb free

Profile Feature Process (non-green material) Solder
(green material) Process

Average Ramp Up Rate (Ts to Tp) 3°C / second Max. 3°C / Second Max.

Preheat
- Temperature Min (Ts Min.) 150°C 100°C
- Temperature Max (Ts Max.) 200°C 150°C
- Time (ts Min to ts Max) 60 to 120 seconds 60 to 120 seconds

Time Maintained Above Critical

Temperature TL:
217°C 183°C
- Temperature (TL)
60 to 150 seconds 60 to 150 seconds
- Time (tL)
Peak Temperature (Tp) 260°C see Figure 9-5
Time within 5°C of actual Peak
30 to 40 seconds 20 to 40 seconds
Temperature (tp)
Ramp Down Rate 6°C / second Max. 6°C / second Max.
Time for T= 25°C to Peak Temperature,
8 minutes Max. 6 minutes Max.
Tp
Table 9.1 Reflow Profile Parameter Values

SnPb Eutectic and Pb free (non-green material)

Package Thickness Volume mm3 < 350 Volume mm3 >=350

< 2.5 mm 235 +5/-0 deg C 220 +5/-0 deg C

≥ 2.5 mm 220 +5/-0 deg C 220 +5/-0 deg C

Pb Free (green material) = 260 +5/-0 deg C

Table 9.2 Package Reflow Peak Temperature

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10 Contact Information

Head Office – Glasgow, UK Branch Office – Tigard, Oregon, USA

Future Technology Devices International Limited (UK) Future Technology Devices International Limited (USA)
Unit 1, 2 Seaward Place, Centurion Business Park 7130 SW Fir Loop
Glasgow G41 1HH Tigard, OR 97223-8160
United Kingdom USA
Tel: +44 (0) 141 429 2777 Tel: +1 (503) 547 0988
Fax: +44 (0) 141 429 2758 Fax: +1 (503) 547 0987

E-mail (Sales) sales1@ftdichip.com E-mail (Sales) us.sales@ftdichip.com

E-mail (Support) support1@ftdichip.com E-mail (Support) us.support@ftdichip.com
E-mail (General Enquiries) admin1@ftdichip.com E-mail (General Enquiries) us.admin@ftdichip.com

Branch Office – Taipei, Taiwan Branch Office – Shanghai, China

Future Technology Devices International Limited (Taiwan) Future Technology Devices International Limited (China)
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System and equipment manufacturers and designers are responsible to ensure that their systems, and any Future Technology Devi ces
International Ltd (FTDI) devices incorporated in their systems, meet all applicable safety, regulatory and system-level performance
requirements. All application-related information in this document (including application descriptions, suggested FTDI devices and other
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Seaward Place, Centurion Business Park, Glasgow G41 1HH, United Kingdom. Scotland Registered Company Number: SC136640

Copyright © Future Technology Devices International Limited 22

 Datasheet
DS_FT312D USB ANDROID HOST IC
Version 1.3

Document No.: FT_000816 Clearance No.: FTDI# 331

Appendix A – References
Document References
White Paper - WP_001 Connecting Peripherals to an Android Platform
FT31XD Android Programmers Guide

Useful utilities and examples firmware

Utilities - FT312D Configuration

Software Examples - Android Projects
FTDI AOA HyperTerm

Copyright © Future Technology Devices International Limited 23

 Datasheet
DS_FT312D USB ANDROID HOST IC
Version 1.3

Document No.: FT_000816 Clearance No.: FTDI# 331

Appendix B - List of Figures and Tables

List of Figures
Figure 2.1 FT312D Block Diagram ................................................................................................... 3
Figure 3.1QFN Schematic Symbol ................................................................................................... 6
Figure 5-1 UART Receive Waveform .............................................................................................. 10
Figure 5-2 UART Transmit Waveform ............................................................................................ 10
Figure 5-3 UART RXD and TXD connection gated by Enumeration ..................................................... 11
Figure 5-4 Inverting Gate Control signal to enable GPS module (active high enable) ........................... 11
Figure 8.1 Application Example showing USB to UART Converter ...................................................... 15
Figure 8.2 Application Example showing USB to RS232 Converter ..................................................... 16
Figure 9-1QFN Package Markings .................................................................................................. 17
Figure 9-2 LQFP Package Markings ................................................................................................ 18
Figure 9-3 QFN-32 Package Dimensions ........................................................................................ 19
Figure 9-4 LQFP-32 Package Dimensions ....................................................................................... 20
Figure 9-5 All packages Reflow Solder Profile ................................................................................. 20

List of Tables
Table 3.1 Power and Ground .......................................................................................................... 6
Table 3.2 Function Pins.................................................................................................................. 7
Table 4.1 Default Descriptor Strings ................................................................................................ 9
Table 6.1 Error Detection ............................................................................................................. 12
Table 7.1 Absolute Maximum Ratings ............................................................................................ 13
Table 7.2 Operating Voltage and Current ....................................................................................... 13
Table 7.3 I/O Pin Characteristics ................................................................................................... 13
Table 7.4 USB I/O Pin (USBDP, USBDM) Characteristics .................................................................. 14
Table 7.5 Crystal Oscillator 1.8 Volts DC Characteristics .................................................................. 14
Table 7.6 ESD and Latch-up Specifications ..................................................................................... 14
Table 9.1 Reflow Profile Parameter Values ..................................................................................... 21
Table 9.2 Package Reflow Peak Temperature .................................................................................. 21

Copyright © Future Technology Devices International Limited 24

 Datasheet
DS_FT312D USB ANDROID HOST IC
Version 1.3

Document No.: FT_000816 Clearance No.: FTDI# 331

Appendix C - Revision History

Document Title: DS_FT312D USB Android Host IC
Document Reference No.: FT_000816
Clearance No.: FTDI# 331
Product Page: https://ftdichip.com/product-category/products/ic/
Document Feedback: Send Feedback

Revision Changes Date

Version 1.0 Initial Datasheet Created 2013-02-01
Note added on USB enumeration to be completed before
Version 1.1 2013-11-15
receiving data in RXD
Version 1.2 Updated Figure 9-3 and Figure 9-4 package dimensions 2019-05-27
Modified Table 6.1 Error Detection
Added MTTF in table 7.1.
1.3 Updated various links & added new links to Useful utilities 25-11-2024
and examples firmware in Appendix A.

Removed section 1.2.

Copyright © Future Technology Devices International Limited 25