LDK320

200 mA high accuracy and high PSRR voltage regulator

Features
• Input voltage from 2.5 to 18 V
SOT23-5L SOT-89 • Very low-dropout voltage (100 mV typ. @ 100 mA load)
• Low quiescent current (typ. 60 μA, 1 μA in off mode)
• High PSRR: 88 dB @ 120 Hz
• Low noise
• Output voltage tolerance: ± 0.5% @ 25 °C (LDK320A) or ± 2% 25 °C
• Output current up to 200 mA
• Wide range of output voltages available on request: fixed from 1.2 V to 12 V
Maturity status link with 100 mV step and adjustable
LDK320 • Logic-controlled electronic shutdown
• Compatible with ceramic capacitor COUT = 1 μF
• Current, SOA and thermal protections
• Available in SOT23-5L and SOT-89 packages
• Temperature range: -40 °C to 125 °C

Applications
• DSC
• TV
• BD, DVD
• PC
• Industrial

Description
The LDK320 is a low drop voltage regulator, which provides a maximum output
current of 200 mA from an input voltage in the range of 2.5 V to 18 V, with a typical
dropout voltage of 100 mV.
It is stabilized with a ceramic capacitor on the output.
The very good dynamic characteristic, combined with low drop voltage and low
quiescent current make it suitable for low power battery-powered applications.
The enable logic control function allows the LDK320 to be in shutdown mode by
consuming a total current lower than 1 μA.
This device also includes a short-circuit current limiting, thermal and SOA
protections.

DS11321 - Rev 11 - June 2024 www.st.com

For further information contact your local STMicroelectronics sales office.
 LDK320
Diagram

1 Diagram

Figure 1. Block diagram (fixed version)

VIN VOUT

Bias
generator
OP-AMP

EN
Enable

Thermal
Bandgap protection
reference

Current
limit

GND

GIPD030820151330MT

Figure 2. Block diagram (adjustable version)

VIN VOUT

Bias
generator
OP-AMP

EN
Enable
ADJ

Thermal
Bandgap protection
reference

Current
limit

GND

DS11321 - Rev 11 page 2/32

 LDK320
Pin configuration

2 Pin configuration

Figure 3. Pin connection (top view)

1 5

3 4
SOT-89 SOT-89 (D configuration)

SOT23-5L

GIPD030820151343MT

Table 1. Pin description (SOT23-5L)

Pin n° Symbol Function

1 IN Input voltage of the LDO

2 GND Common ground
3 EN Enable pin logic input: low = shutdown, high = active
4 ADJ/NC Adjustable pin on ADJ version, not connected on fixed version
5 OUT Output voltage of the LDO

Table 2. Pin description (SOT-89)

Pin n° Symbol Function

1 OUT Output voltage of the LDO

2 GND Common ground
3 IN Input voltage of the LDO
TAB GND Common ground

Table 3. Pin description (SOT-89, D configuration)

Pin n° Symbol Function

1 GND Common ground

2 IN Input voltage of the LDO
3 OUT Output voltage of the LDO
TAB IN Input voltage of the LDO

DS11321 - Rev 11 page 3/32

 LDK320
Typical application

3 Typical application

Figure 4. Typical application circuits

VIN VO U T VI N VO U T
VI VO VI VO
ON ON
EN L D K 32 0 E N L D K 32 0
O FF O FF R1
CI N CO U T CI N CO U T
1 µF 1 µF
G ND 1 µF ADJ
G ND 1 µF

R2

VO= V A D J (1+R1/R2)

F ix e d output volta ge ve rs ion Adjustable output voltage version

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Note: Adjustable version and enable pin are not available on SOT-89 package.

DS11321 - Rev 11 page 4/32

 LDK320
Maximum ratings

4 Maximum ratings

Table 4. Absolute maximun ratings

Symbol Parameter Value Unit

VIN DC input voltage - 0.3 to 20 V

VOUT DC output voltage - 0.3 to VI + 0.3 V

VEN Enable input voltage - 0.3 to VI + 0.3 V

VADJ ADJ pin voltage - 0.3 to 2 V

IOUT Output current Internally limited mA

PD (1) Power dissipation Internally limited mW

TSTG Storage temperature range - 65 to 150 °C

Operating junction temperature

TOP - 40 to 125 °C
range

1. Maximum power dissipation must be calculated by taking into account the package and thermal performance.

Note: Absolute maximum ratings are those values beyond which damage to the device may occur. Functional
operation under these conditions is not implied. All values are referred to GND.

Table 5. Thermal data

Symbol Parameter SOT23-5L SOT-89 Unit

RthJA Thermal resistance junction-ambient 160 110 °C/W

RthJC Thermal resistance junction-case 68 15 °C/W

DS11321 - Rev 11 page 5/32

 LDK320
Electrical characteristics

5 Electrical characteristics

TJ = 25 °C, VIN = VOUT(NOM) + 1 V, CIN = COUT = 1 μF, IOUT = 1 mA, VEN = VIN, unless otherwise specified.

Table 6. LDK320 electrical characteristics (fixed output version)

Symbol Parameter Test conditions Min. Typ. Max. Unit

VIN Operating input voltage 2.5 18 V

TJ = 25 °C -2 2 %
VOUT accuracy
-40 °C < TJ < 125 °C -3 3 %
VOUT
TJ = 25 °C -0.5 0.5 %
VOUT accuracy, LDK320A
-40 °C < TJ < 125 °C -1.5 1.5 %

ΔVOUT Static line regulation VOUT +1 V ≤ VIN ≤ 18 V 0.001 0.05 %/V

IOUT = 1 mA to 200 mA,

10 15 mV
VOUT ≤ 2 V
Static load regulation
ΔVOUT
(SOT23-5L) IOUT = 1 mA to 200 mA,
0.001 0.003 %/mA
VOUT > 2 V

IOUT = 1 mA to 200 mA,

10 25 mV
VOUT ≤ 2 V
Static load regulation
ΔVOUT
(SOT-89) IOUT = 1 mA to 200 mA,
0.001 0.004 %/mA
VOUT > 2 V

IOUT = 100 mA,

100
VOUT = 3.3 V
VDROP Dropout voltage (1)
IOUT = 200 mA, VOUT = 3.3 V
200 350 mV
-40 °C < TJ < 125 °C

10 Hz to 100 kHz,
eN Output noise voltage 63 μVRMS/V
IOUT = 10 mA

f = 120 Hz, IOUT = 10 mA,

88
VOUT = 3.3 V

f = 1 kHz IOUT = 10 mA,

SVR Supply voltage rejection 65 dB
VOUT = 3.3 V

f = 10 kHz, IOUT= 10 mA
48
VOUT = 3.3 V

VOUT +1 V VIN 18 V,
IOUT = 0 mA, 60 90
-40 °C < TJ < 125 °C
IQ Quiescent current VIN = VOUT +1 V IOUT = 200 mA, μA
70 100
-40 °C < TJ < 125 °C

VIN input current in OFF mode:

0.2 1
VEN = GND TJ = 25 °C

RL = 0 330
ISC Short-circuit current mA
RL = 0, VIN = 16 V 200

DS11321 - Rev 11 page 6/32

 LDK320
Electrical characteristics

Symbol Parameter Test conditions Min. Typ. Max. Unit

VIN = 2.5 V to 18 V,
Enable input logic low 0.4
-40 °C < TJ < 125 °C
VEN V
VIN = 2.5 V to 18 V,
Enable input logic high 1.2
-40 °C < TJ < 125 °C

IEN Enable pin input current VEN = VIN 0.1 100 nA

Thermal shutdown 160

TSHDN °C
Hysteresis 20
Capacitance (see
COUT Output capacitor Section 6: Typical 1 22 µF
characteristics)

1. Dropout voltage is the input-to-output voltage difference at which the output voltage is 100 mV below its nominal value.

TJ = 25 °C, VIN = 2.5 V, CIN = COUT = 1 μF, IOUT = 1 mA, VEN = VIN, unless otherwise specified.

DS11321 - Rev 11 page 7/32

 LDK320
Electrical characteristics

Table 7. LDK320 electrical characteristics (ADJ version)

Symbol Parameter Test conditions Min. Typ. Max. Unit

VIN Operating input voltage 2.5 18 V

Adjustable voltage TJ = 25 °C 1.185 V

TJ = 25 °C -2 +2
Adjustable voltage accuracy %
-40 °C < TJ < 125 °C -3 +3
VADJ
Adjustable voltage,
TJ = 25 °C 1.2 V
LDK320A
TJ = 25 °C -0.5 +0.5
Adjustable voltage accuracy,
%
LDK320A -40 °C < TJ < 125 °C -1.5 +1.5

ΔVOUT Static line regulation VOUT + 1 V ≤ VIN ≤ 18 V 0.001 0.05 %/V

ΔVOUT Static load regulation IOUT = 1 mA to 200 mA 0.0002 0.003 %/mA

IOUT = 100 mA, VOUT = 3.3 V 100

VDROP Dropout voltage (1) IOUT = 200 mA, VOUT = 3.3 V mV
200 350
-40 °C < TJ < 125 °C

eN Output noise voltage 10 Hz to 100 kHz IOUT = 10 mA 60 μVRMS

IADJ Adjust pin current 1 μA

f = 120 Hz IOUT = 10 mA,

83
VOUT = VADJ

f = 1 kHz IOUT = 10 mA,

SVR Supply voltage rejection 73 dB
VOUT = VADJ

f = 10 kHz IOUT = 10 mA,

58
VOUT = VADJ

VOUT +1 V ≤ VIN ≤ 18 V,
IOUT = 0 mA, 50 90
-40 °C < TJ < 125 °C

VIN = VOUT + 1 V,
IQ Quiescent current μA
IOUT = 200 mA, 60 100
-40 °C < TJ < 125 °C

VIN input current in OFF mode:

0.2 1
VEN = GND, TJ = 25 °C

RL = 0 330
ISC Short-circuit current mA
RL = 0, VIN = 16 V 200

VIN = 2.5 V to 18 V,
Enable input logic low 0.4
-40 °C < TJ < 125 °C
VEN V
VIN = 2.5 V to 18 V,
Enable input logic high 1.2
-40 °C < TJ < 125 °C

IEN Enable pin input current VEN = VIN 0.1 100 nA

Thermal shutdown 160

TSHDN °C
Hysteresis 20

DS11321 - Rev 11 page 8/32

 LDK320
Electrical characteristics

Symbol Parameter Test conditions Min. Typ. Max. Unit

Capacitance (see
COUT Output capacitor Section 6: Typical 1 22 μF
characteristics)

DS11321 - Rev 11 page 9/32

 LDK320
Typical characteristics

6 Typical characteristics

Unless otherwise specified: TJ = 25 °C, VIN = VOUT(NOM) + 1 V, CIN = COUT = 1 μF.

Figure 5. Output voltage vs. temperature (VIN = 2.5 V, Figure 6. Output voltage vs. temperature (VIN = 2.5 V,
VOUT = VADJ, IOUT = 1 mA) VOUT = VADJ, IOUT = 200 mA)

1.24 1.24

1.22 1.22

1.2
Output voltage [V]

voltage [V]
1.2

Output Voltage
1.18 1.18

1.16 1.16

1.14 1.14
-40 -25 0 25 55 85 125 -40 -25 0 25 55 85 125
Temperature [ °C] Temperature [ °C]

GIPD040820151207MT GIPD040820151208MT

Figure 7. Output voltage vs. temperature (VIN = 4.3 V,

Figure 8. Output voltage vs. temperature (VIN = 4.3 V,
VOUT = 3.3 V, IOUT = 1 mA)
VOUT = 3.3 V, IOUT = 200 mA)

3.37
3.37

3.35
3.35

3.33
Output Voltage [V]

3.33
Output Voltage [V]

3.31
3.31

3.29
3.29

3.27
-40 -25 0 25 55 85 125
3.27
-40 -25 0 25 55 85 125 Temperature [ °C]
Temperature [ °C]
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DS11321 - Rev 11 page 10/32

 LDK320
Typical characteristics

Figure 9. Line regulation vs. temperature (VIN = 4.3 to Figure 10. Line regulation vs. temperature (VIN = 2.5 to
18 V, VOUT = 3.3 V, IOUT = 1 mA) 18 V, VOUT = VADJ, IOUT = 1 mA)

0.3 0.3

0.25 0.25

Line Regulation [% / V]
Line Regulation [% / V]

0.2 0.2

0.15 0.15

0.1 0.1

0.05 0.05

0 0
-40 -25 0 25 55 85 125 -40 -25 0 25 55 85 125

Temperature [ °C] Temperature [ °C]

GIPD040820151211MT GIPD040820151212MT

Figure 11. Load regulation vs. temperature (VIN = 4.3 V, Figure 12. Load regulation vs. temperature (VIN = 2.5 V,
VOUT = 3.3 V, IOUT = 1 to 200 mA) VOUT = VADJ, IOUT = 1 to 200 mA)

0.01 0.005

0.008 0.004
Load Regulation [% / mA]

Load Regulation [% / mA]

0.006 0.003

0.004 0.002

0.002 0.001

0 0
-40 -25 0 25 55 85 125 -40 -25 0 25 55 85 125
Temperature [ °C] Temperature [ °C]

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Figure 13. Enable thresholds vs. temperature

Figure 14. Dropout voltage vs. temperature
(IOUT = 1 mA)
300
1
275

250
0.9 VENL VENH
225
IOUT =100mA
0.8 200

175 IOUT =200mA

[mV]

0.7
VEN Enable [V]

150
VDROP

125
0.6
100

0.5 75

50

0.4 25

0
0.3 -40 -25 0 25 55 85 125
-40 -25 0 25 55 85 125 Temperature [ °C]
Temperature [ °C]
GIPD040820151216MT
GIPD040820151215MT

DS11321 - Rev 11 page 11/32

 LDK320
Typical characteristics

Figure 15. Quiescent current vs. input voltage Figure 16. Quiescent current vs. temperature (IOUT = 1
(IOUT = 1 mA) mA)

120 100

110 T=-40°C VIN =4.3V

90
VIN =10V
100 T=25°C
VIN =18V
80
T=125°C
90
70
80

60
70
Iq [uA]

Iq [uA]
60 50

50
40

40
30
30
20
20

10
10

0 0
2.5 10 18 -40 -25 0 25 55 85 125
VIN [V] Temperature [°C]

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Figure 17. Quiescent current vs. output current Figure 18. Quiescent current vs. temperature
(VIN = 4.3 V) (IOUT = 200 mA)

100 100

T=-40°C
90 90
VIN =4.3V
T=25°C
80 80
T=125°C

70 70

60 60
Iq [uA]
Iq [uA]

50 50

40 40

30 30

20 20

10 10

0 0
1 100 200 -40 -25 0 25 55 85 125
IOUT [mA] Temperature [°C]

GIPD040820151219MT GIPD040820151220MT

Figure 19. Off-state current vs. temperature Figure 20. Short-circuit current vs. temperature
(VIN = 4.3 V)

0.4

0.38

0.36

0.34

0.32
ISC

0.3

0.28

0.26

0.24

0.22

0.2
-40 -25 0 25 55 85 125

Temperature [°C]
GIPD040820151222MT

DS11321 - Rev 11 page 12/32

 LDK320
Typical characteristics

Figure 21. Dropout voltage vs. IOUT Figure 22. Short-cicuit current vs. drop voltage

500 0.4

T=-40°C 0.35
T=25°C
400
T=125°C 0.3

0.25
VDROP [mV]

300

ISC [A]
0.2

200
0.15

0.1
100

0.05

0 0
1 100 200 0 2 4 6 8 10 12 14 16 18 20
IOUT [mA] VDROP [V]
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Figure 23. SVR vs. frequency Figure 24. Output noise spectral density
T = 25 °C, IOUT =10 mA, for VOUT = 3.3 V then VIN= 3.8 to 4.3 V, for
VOUT = VADJ then VIN = 2.5 to 3 V VIN = VOUT+1 V, IOUT =10 mA, CIN = COUT = 1μ F, T = 25 °C
100 20

90

80 Vout=3.3V Vout=Vadj
15
Vout=Vadj
70
Vout=3.3V
eN [uV/SQRT(Hz)]

60
SVR [dB]

50 10

40

30
5
20

10

0 0
100 1000 10000 100000 10.0 100.0 1000.0 10000.0 100000.0
Frequency [Hz] Frequency [Hz]
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Figure 25. Stability plan (VOUT = 3.3 V) Figure 26. Stability plan (VOUT = VADJ)

IOUT from 10 mA to 0.2 A for VIN = 4.3 V, IOUT = 0.18 A for VIN = 18 V, CIN = 1 μF, T = 25 °C IOUT from 10 mA to 0.2 A for VIN = 2.5V, IOUT = 0.18 A for VIN = 18 V, CIN=1 μF, T = 25 °C
ESR@100 KHz [ Ω]

1 1
ESR@100KHz [Ω]

0.1 0.1

0.01 0.01
1 2.2 4.7 10 22 1 2.2 4.7 10 22
COUT [uF] (nominal value) COUT [uF] (nominal value)
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DS11321 - Rev 11 page 13/32

 LDK320
Typical characteristics

Figure 27. Startup with enable (VOUT = 3.3 V) Figure 28. Startup with enable (VOUT = VADJ)

VIN = 4.3 V, VEN = from 0 to Vin, IOUT = 200 mA, CIN = COUT = 1 μF trise = tfall = 1 μs VIN = 18 V, VEN = from 0 to Vin, IOUT =200 mA, CIN = COUT =1 μF trise = tfall = 1 μs

Ch1=VEN Ch1=VEN

Ch2=VOUT Ch2=VOUT

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Figure 29. Turn-on time (VOUT = 3.3 V) Figure 30. Turn-on time (VOUT = VADJ)

VIN = VEN = from 0 to 4.3 V, IOUT = 200 mA, CIN = COUT = 1 μF, Trise = 1 μs VIN = VEN = from 0 to 18 V, IOUT = 200 mA VOUT = VREF, CIN = COUT = 1 μF Trise = 5 μs

Ch1=VIN

Ch1=VIN

Ch2=VOUT
Ch2=VOUT

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Figure 31. Line transient (VOUT = 3.3 V, rise) Figure 32. Line transient (VOUT = 3.3 V, fall)

VIN = VEN = from 4.3 to 8.3 V, IOUT = 10 mA, CIN = COUT = 1 μF Trise = 5 μs VIN = VEN = from 4.3 to 8.3 V, IOUT =10 mA, CIN = COUT =1 μF Tfall = 5 μs

Ch1=VIN
Ch1=VIN

Ch2=VOUT

Ch2=VOUT

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DS11321 - Rev 11 page 14/32

 LDK320
Typical characteristics

Figure 33. Load transient (VOUT = 3.3 V, rise)

Figure 34. Load transient (VOUT = VADJ, fall)
VIN = VEN = 4.3 V, IOUT = from 1 to 200 mA, CIN = COUT = 1 μF Trise = 5 μs
VIN = VEN = 2.5 V, IOUT = from 1 to 200 mA, CIN = COUT = 1 μF Trise - Tfall = 5 μs

Ch2=VOUT
Ch4=IOUT

Ch1=VOUT

Ch4=IOUT

GIPD040820151237bMT
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DS11321 - Rev 11 page 15/32

 LDK320
Package information

7 Package information

In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK packages,
depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product
status are available at: www.st.com. ECOPACK is an ST trademark.

7.1 SOT23-5L package information

Figure 35. SOT23-5L package outline (option A)

DS11321 - Rev 11 page 16/32

 LDK320
Package information

Table 8. SOT23-5L mechanical data (option A)

Dimensions (mm)

Symbol Min. Nom. Max.

A - - 1.25
A1 0.04 - 0.10
A2 1.00 1.10 1.20
b 0.33 - 0.41
b1 0.32 0.35 0.38
c 0.15 - 0.19
c1 0.14 0.15 0.16
D 2.82 2.92 3.02
E 2.60 2.80 3.00
E1 1.50 1.60 1.70
e 0.95 BSC
e1 1.90 BSC
L 0.30 - 0.60
Θ 0° 8°

DS11321 - Rev 11 page 17/32

 LDK320
Package information

7.2 SOT23-5L package information

Figure 36. SOT23-5L package outline (option B)

DS11321 - Rev 11 page 18/32

 LDK320
Package information

Table 9. SOT23-5L package mechanical data (option B)

mm
Dim.
Min. Typ. Max.

A 0.90 1.45
A1 0 0.15
A2 0.90 1.30
b 0.30 0.50
c 0.14 0.20
c1 0.14 0.15 0.16
D 2.90 BSC
E 2.80 BSC
E1 1.60 BSC
e 0.95 BSC
e1 1.90 BSC
L 0.30 0.55
L2 0.25
N 5
θ 0° 8°
Tolerance
aaa 0.15
bbb 0.20
ccc 0.10
ddd 0.20
eee 0.08

Figure 37. SOT23-5L recommended footprint

Note: Dimensions are in mm

DS11321 - Rev 11 page 19/32

 LDK320
Package information

7.3 SOT23-5L packing information

Figure 38. SOT23-5L tape and reel outline

Table 10. SOT23-5L tape and reel mechanical data

mm
Dim.
Min. Typ. Max.

A 180
C 12.8 13.0 13.2
D 20.2
N 60
T 14.4
Ao 3.13 3.23 3.33
Bo 3.07 3.17 3.27
Ko 1.27 1.37 1.47
Po 3.9 4.0 4.1
P 3.9 4.0 4.1

DS11321 - Rev 11 page 20/32

 LDK320
Package information

7.4 SOT-89 package information

Figure 39. SOT-89 package outline

7098166_REV_F

DS11321 - Rev 11 page 21/32

 LDK320
Package information

Table 11. SOT-89 mechanical data

mm
Dim.
Min. Typ. Max.

A 1.40 1.60
B 0.44 0.56
B1 0.36 0.48
C 0.35 0.44
C1 0.35 0.44
D 4.40 4.60
D1 1.62 1.83
D3 0.90
E 2.29 2.60
e 1.42 1.57
e1 2.92 3.07
H 3.94 4.25
H1 2.70 3.10
K 1° 8°
L 0.89 1.20
R 0.25
β 90°

DS11321 - Rev 11 page 22/32

 LDK320
Package information

Figure 40. SOT-89 recommended footprint

Footprint

DS11321 - Rev 11 page 23/32

 LDK320
Package information

7.5 SOT-89 packing information

Figure 41. SOT-89 carrier tape outline

7111762_5

Figure 42. SOT-89 device orientation

DS11321 - Rev 11 page 24/32

 LDK320
Package information

Table 12. SOT-89 carrier tape mechanical data

mm
Dim.
Value Tolerance

Ao 4.91 ± 0.10
Bo 4.52 ± 0.10
Ko 1.90 ± 0.10
F 5.50 ± 0.10
E 1.75 ± 0.10
W 12 ± 0.30
P2 2 ± 0.10
Po 4 ± 0.10
P1 8 ± 0.10
T 0.30 ± 0.10
D Ø 1.55 ± 0.05
D1 Ø 1.60 ± 0.10

DS11321 - Rev 11 page 25/32

 LDK320
Package information

Figure 43. SOT-89 reel drawing

DS11321 - Rev 11 page 26/32

 LDK320
Ordering information

8 Ordering information

Table 13. Order code

SOT-89
SOT23-5L SOT-89 Marking Accuracy (%) Output voltage
(D configuration)

LDK320AM-R ADA 0.5

ADJ
LDK320M-R KAD 2

LDK320AM12R (1) 0.5

1.2
LDK320M12R (1) 2

LDK320AM15R (1) 15A 0.5 1.5

LDK320AM18R (1) 18A 0.5

1.8
LDK320M18R K18 2
LDK320AM25R 25A 0.5
2.5
LDK320M25R K25 2
LDK320AM30R 30A 0.5
LDK320ADU30R 30 0.5 3
LDK320M30R K30 2
LDK320AM33R 33A 0.5
LDK320ADU33R 33 0.5 3.3
LDK320M33R K33 2
LDK320AM36R 36A 0.5 3.6
LDK320AM50R 50A 0.5
LDK320ADU50R 50 0.5
5
LDK320AU50R E0 0.5
LDK320M50R K50 2
LDK320AM120R 120A 0.5
LDK320ADU120R A2 0.5 12

LDK320M120R (1) 2

1. Available on request.

DS11321 - Rev 11 page 27/32

 LDK320

Revision history
Table 14. Document revision history

Date Revision Changes

16-Nov-2015 1 First release.

Document status promoted from preliminary data to production data.
Updated title and features in cover page.
01-Jun-2016 2
Updated Section 8: “Ordering information”.
Minor text changes.
Updated Section 8: "Ordering information".
05-Jul-2017 3
Minor text changes.
Updated ΔVOUT test condition in Table 6. LDK320 electrical characteristics (fixed
09-Oct-2018 4 output version).
Added new order code LDK320AU50R in Table 12. Order code.
Added ΔVOUT for SOT-89 in Table 6. LDK320 electrical characteristics (fixed output
28-Oct-2019 5
version).
23-Jul-2020 6 Updated Figure 2. Block diagram (adjustable version).
10-Nov-2020 7 Updated Table 12. Order code.
12-Nov-2020 8 Added new Marking column in Table 13. Order code.
Updated Section 7.2.
26-Apr-2022 9
Added new Section 7.1 SOT23-5L package information.
05-Dec-2023 10 Updated VADJ and VDROP test conditions in Table 7.
04-Jun-2024 11 Updated Figure 35

DS11321 - Rev 11 page 28/32

 LDK320
Contents

Contents
1 Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
2 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3 Typical application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
4 Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
5 Electrical characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6 Typical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
7 Package information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
7.1 SOT23-5L package information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
7.2 SOT23-5L package information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7.3 SOT23-5L packing information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
7.4 SOT-89 package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
7.5 SOT-89 packing information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8 Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
List of tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
List of figures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

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List of tables

List of tables
Table 1. Pin description (SOT23-5L) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Table 2. Pin description (SOT-89). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Table 3. Pin description (SOT-89, D configuration) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Table 4. Absolute maximun ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Table 5. Thermal data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Table 6. LDK320 electrical characteristics (fixed output version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 7. LDK320 electrical characteristics (ADJ version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Table 8. SOT23-5L mechanical data (option A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Table 9. SOT23-5L package mechanical data (option B) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Table 10. SOT23-5L tape and reel mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 11. SOT-89 mechanical data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Table 12. SOT-89 carrier tape mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 13. Order code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Table 14. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

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List of figures

List of figures
Figure 1. Block diagram (fixed version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Figure 2. Block diagram (adjustable version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Figure 3. Pin connection (top view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Figure 4. Typical application circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Figure 5. Output voltage vs. temperature (VIN = 2.5 V, VOUT = VADJ, IOUT = 1 mA) . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 6. Output voltage vs. temperature (VIN = 2.5 V, VOUT = VADJ, IOUT = 200 mA) . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 7. Output voltage vs. temperature (VIN = 4.3 V, VOUT = 3.3 V, IOUT = 1 mA) . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 8. Output voltage vs. temperature (VIN = 4.3 V, VOUT = 3.3 V, IOUT = 200 mA) . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 9. Line regulation vs. temperature (VIN = 4.3 to 18 V, VOUT = 3.3 V, IOUT = 1 mA) . . . . . . . . . . . . . . . . . . . . . . 11
Figure 10. Line regulation vs. temperature (VIN = 2.5 to 18 V, VOUT = VADJ, IOUT = 1 mA) . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 11. Load regulation vs. temperature (VIN = 4.3 V, VOUT = 3.3 V, IOUT = 1 to 200 mA) . . . . . . . . . . . . . . . . . . . . . 11
Figure 12. Load regulation vs. temperature (VIN = 2.5 V, VOUT = VADJ, IOUT = 1 to 200 mA) . . . . . . . . . . . . . . . . . . . . . 11
Figure 13. Enable thresholds vs. temperature (IOUT = 1 mA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 14. Dropout voltage vs. temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 15. Quiescent current vs. input voltage (IOUT = 1 mA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 16. Quiescent current vs. temperature (IOUT = 1 mA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 17. Quiescent current vs. output current (VIN = 4.3 V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 18. Quiescent current vs. temperature (IOUT = 200 mA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 19. Off-state current vs. temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 20. Short-circuit current vs. temperature (VIN = 4.3 V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 21. Dropout voltage vs. IOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 22. Short-cicuit current vs. drop voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 23. SVR vs. frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 24. Output noise spectral density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 25. Stability plan (VOUT = 3.3 V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 26. Stability plan (VOUT = VADJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 27. Startup with enable (VOUT = 3.3 V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 28. Startup with enable (VOUT = VADJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 29. Turn-on time (VOUT = 3.3 V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 30. Turn-on time (VOUT = VADJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 31. Line transient (VOUT = 3.3 V, rise) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 32. Line transient (VOUT = 3.3 V, fall) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 33. Load transient (VOUT = 3.3 V, rise) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 34. Load transient (VOUT = VADJ, fall) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 35. SOT23-5L package outline (option A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 36. SOT23-5L package outline (option B) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Figure 37. SOT23-5L recommended footprint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 38. SOT23-5L tape and reel outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 39. SOT-89 package outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Figure 40. SOT-89 recommended footprint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 41. SOT-89 carrier tape outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 42. SOT-89 device orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 43. SOT-89 reel drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

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