Ordering number : ENN6518

Monolithic Linear IC

LA6538T
Single-Phase Full-Wave Fan Motor Driver

Overview • Ultraminiature package

(MSOP-8: 3.0 × 4.9 × 0.93 mm3)
The LA6538T is optimal for use as a fan motor driver in
— Allows the circuit board to be miniaturized and a
equipment, such as notebook personal computers and
large heat sink to be used.
electronic game units, that requires miniaturization and
low noise levels. This device achieves highly efficient Reference materials:
single-phase bipolar fan motor drive by providing a low
T package (MSOP-8) series fan motor drivers
saturation voltage BTL output.
LB1964T: 3 and 5 V operation, low saturation voltage
Functions and Features switching single-phase bipolar drive, FG output
• BTL output single-phase full-wave linear drive (gain LB11963T: 5 and 12 V operation, switching single-
resistance: 180 to 500 kΩ, 360×) phase bipolar drive, restart circuit, lock detection, 1/2
— Since this device generates no switching noise, it is FG output
optimal for fan drive in audio equipment, electronic LB11964T: 5 and 12 V operation, switching single-
games, and notebook personal computers. phase bipolar drive, restart circuit, lock detection, FG
• Supports low-voltage operation and features a wide output
usable voltage range (VCC = 2.5 to 9.5 V).
• Low saturation voltage output (Upper side + lower side Package Dimensions
saturation voltage: VOsat(total) = 0.2 V (typ), unit: mm
IO = 100 mA)
3245-MSOP8
— This device achieves a high coil efficiency for low
current drain, and generates minimal heat in the IC [LA6538T]
3.0
itself.
• Constant-voltage Hall bias output. 8 5
— The Hall element is regulated at 2.1 V, and the
0.5

device provides a stable Hall output with excellent

3.0
4.9

temperature characteristics.
• FG output
— The LA6538T provides a speed detection output (an 0.65
1 4
open-collector output). (0.5) 0.25 0.25

• Built-in thermal protection circuit

1.1max

— This circuit limits the drive current to prevent

(0.85)

damage to or destruction of the IC when the IC chip

temperature exceeds 180°C due to excessive output
current caused by load shorting or other problem.
0.08

SANYO: MSOP8

Any and all SANYO products described or contained herein do not have specifications that can handle
applications that require extremely high levels of reliability, such as life-support systems, aircraft’s
control systems, or other applications whose failure can be reasonably expected to result in serious
physical and/or material damage. Consult with your SANYO representative nearest you before using
any SANYO products described or contained herein in such applications.
SANYO assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other
parameters) listed in products specifications of any and all SANYO products described or contained
herein.

SANYO Electric Co.,Ltd. Semiconductor Company

TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN
83000RM (OT) No. 6518-1/6
 LA6538T

Pd max — Ta
600
Specified printed circuit board:

Allowable power dissipation, Pdmax — mW

20.0 × 10.0 × 0.8 mm3
500 Paper phenolic board
Mounted on the specified
printed circuit board
400

300

200
192

100

0
--20 0 20 40 60 80 100
Ambient temperature, Ta — °C ILA00211

Specifications
Maximum Ratings at Ta = 25°C
Parameter Symbol Conditions Ratings Unit
Maximum supply voltage VCC max 10 V
Allowable power dissipation Pd max Mounted on the specified printed circuit board* 400 mW
OUT pin output current IOUT max 0.3 A
OUT pin output voltage handling VOUT max 9.5 V
FG output voltage handling VFG max 10 V
FG output current IFG max 5 mA
Operating temperature Topr –20 to +90 °C
Storage temperature Tstg –55 to +150 °C

Note: * Specified printed circuit board: 20.0 × 10.0 × 0.8 mm3 paper phenolic board, wiring density: 20%.

Recommended Operating Conditions at Ta = 25°C

Parameter Symbol Conditions Ratings Unit
Supply voltage VCC 2.5 to 9.5 V
Hall input common-mode input voltage range VICM 0.9 to VCC – 1 V

Electrical Characteristics at Ta = 25°C, VCC = 5 V

Ratings
Parameter Symbol Conditions Unit
min typ max
Circuit current ICC IN– = 2.6 V, IN+ = 2.4 V, RL = ∞ 10 15 mA
OUT pin output low-level voltage VOL IO = 100 mA 0.1 0.2 V
OUT pin output high-level voltage VOH IO = 100 mA 0.1 0.2 V
Hall bias voltage VHB RH = 360 Ω + 91 Ω 1.9 2.1 2.3 V
Hall amplifier gain VG 47 50 53 dB
Hall amplifier input resistance VINR 400 500 620 Ω
FG output low-level voltage VFG IFG = 3 mA 0.2 0.3 V
FG output leakage current IFGL VFG = 7 V 30 µA
Thermal protection circuit T-TSD Design guarantee* 150 180 200 °C
Note: * Design guarantee: Indicates a design target value. These parameters are not tested in the independent IC.

Truth Table
IN– IN+ OUT1 OUT2 FG Mode
H L H L L
Motor operating
L H L H off
— — off off — Thermal protection activated

No. 6518-2/6
 LA6538T

Pin Assignment

IN+ 1 8 FG

HB 2 7 VCC

LA6538T
IN-- 3 6 OUT2

OUT1 4 5 GND

Top view
ILA00206

Sample Application Circuit

VCC
Di Cr *4
*1 VCC

*3
FG R2
HB
*2
H IN-- OUT1 H

IN+ OUT2

R1 R2
GND

Devices on the
printed circuit board

ILA00207 ILA00208

Notes: 1. When the diode Di is used to prevent device destruction from reverse connection, the capacitor Cr must be inserted to assure a path for
regenerative currents. Similarly, if there are no nearby capacitors on the fan power supply line, the capacitor Cr is also required to increase
reliability.
2. The Hall element is biased at a constant voltage of approximately 2.1 V from the HB pin. Thus the LA6538T provides a stable Hall output with
excellent temperature characteristics. The resistor R1 adjusts the Hall output amplitude.
The LA6538T implements linear drive by amplifying the Hall output and applying voltage control to the motor coils. Startup characteristics and
efficiency are improved by using a higher Hall device output. However, the motor can be made to operate more quietly by adjusting the Hall device.
3. If the Hall bias is taken from VCC, bias the Hall device at 1/2 VCC as shown in the figure.
4. This pin must be left open if unused.

Block Diagram
VCC

FG
2.1 VRG 180 kΩ 180 kΩ

HB
IN+ 500 Ω 500 Ω
OUT1 OUT2
H

IN--

GND

ILA00209

No. 6518-3/6
 LA6538T

Timing Chart

Hall Signal

OUTPUT

Coil Current

FG Pulse

ILA00210

No. 6518-4/6
 LA6538T

ICC — VCC VO(sat) — IO

18 0.7
VCC = 8.5 V

)
-- = L

PN
Output saturation voltage, VO(sat) — V
16

N
IN 0.6

(
T1
IN-- = IN+ = HB

U
14

O
Current drain, ICC — mA

0.5

)
NP
12

)
PN
IN-- = IN+ = 1/2 VCC

(P
+ =L

T2

(N
10 0.4

OU
IN

T2
OU
l )
NP
8 0.3 ta (P
to
T1
6 OU
0.2
4

0.1
2

0 0
0 2 4 6 8 10 12 0 100 200 300 400
Supply voltage, VCC — V ILA00212 Output current, IO — mA ILA00213
VO(sat) — IO VO(sat) — IO
0.6 0.6
OUT2 pnp (upper side) OUT1 npn (lower side)

Output saturation voltage, VO(sat) — V

Output saturation voltage, VO(sat) — V

V
V
N8
0.5 0.5

N5
NP
V

NP
P8
PN

0.4 0.4
V
P5
PN

0.3 0.3

V
N3
NP
0.2 0.2
3V
P
PN

0.1 0.1

0 0
0 100 200 300 400 0 100 200 300 400
Output current, IO — mA ILA00214 Output current, IO — mA ILA00215
FG Threshold Level VFG(sat) — IFG
0.6
VCC = 5 V
Saturation voltage, VFG(sat) — V

0.5

0.4

FG = “H”
VFG

H 0.3

0.2
9V 5V
3V
0.1
FG = “L”
L 0
0 1 2 3 0 1 2 3 4 5 6 7 8 9 10
Output voltage, VOUT2 — V ILA00216 FG supply current, IFG — mA ILA00217
VHB — IHB Gain Characteristics
2.8 6
VCC = 5 V VCC = 5 V
1/2 VCC bias
2.4
9V 5
Hall bias voltage, VHB — V

3V
Output voltage, VO — V

2.0
5V 4

1.6
3
1.2

2
0.8

1
0.4

0 0
0 2 4 6 8 10 --40 --30 --20 --10 0 10 20 30 40
Hall bias current, IHB — mA ILA00218 (IN--) — (IN+) -- mV ILA00219

No. 6518-5/6
 LA6538T

Specifications of any and all SANYO products described or contained herein stipulate the performance,
characteristics, and functions of the described products in the independent state, and are not guarantees
of the performance, characteristics, and functions of the described products as mounted in the customer’s
products or equipment. To verify symptoms and states that cannot be evaluated in an independent device,
the customer should always evaluate and test devices mounted in the customer’s products or equipment.
SANYO Electric Co., Ltd. strives to supply high-quality high-reliability products. However, any and all
semiconductor products fail with some probability. It is possible that these probabilistic failures could
give rise to accidents or events that could endanger human lives, that could give rise to smoke or fire,
or that could cause damage to other property. When designing equipment, adopt safety measures so
that these kinds of accidents or events cannot occur. Such measures include but are not limited to protective
circuits and error prevention circuits for safe design, redundant design, and structural design.
In the event that any or all SANYO products (including technical data, services) described or contained
herein are controlled under any of applicable local export control laws and regulations, such products must
not be exported without obtaining the export license from the authorities concerned in accordance with the
above law.
No part of this publication may be reproduced or transmitted in any form or by any means, electronic or
mechanical, including photocopying and recording, or any information storage or retrieval system,
or otherwise, without the prior written permission of SANYO Electric Co., Ltd.
Any and all information described or contained herein are subject to change without notice due to
product/technology improvement, etc. When designing equipment, refer to the “Delivery Specification”
for the SANYO product that you intend to use.
Information (including circuit diagrams and circuit parameters) herein is for example only; it is not
guaranteed for volume production. SANYO believes information herein is accurate and reliable, but
no guarantees are made or implied regarding its use or any infringements of intellectual property rights
or other rights of third parties.

This catalog provides information as of August, 2000. Specifications and information herein are subject to
change without notice.

PS No. 6518-6/6