NCR320U / NCR321U
250 mA LED driver in SOT457
Rev. 1 — 11 December 2018
Product data sheet
1. Product profile
1.1. General description
LED driver consisting of a resistor-equipped NPN transistor with two diodes on one chip in an
SOT457 (SC-74; TSOP6) plastic package.
Table 1. Product overview
Type number
NCR320U
NCR321U
Package
Nexperia
SOT457
SOT457
JEITA
SC-74; TSOP6
SC-74; TSOP6
1.2. Features and benefits
•
•
•
•
•
•
•
•
•
Stabilized output current of 10 mA without external resistor
Stabilized output current adjustable up to 250 mA when an external resistor is used
High current accuracy at supply voltage variation
Low voltage overhead of 1.4 V
Reduces component count and board space
High power dissipation of 750 mW
Supply voltage up to 16 V
Digital PWM input up to 10 kHz frequency for NCR321U
AEC-Q101 qualified
1.3. Applications
•
•
•
•
Constant current LED driver
Generic constant current source
Automotive applications (for example: interior lighting, dash board, instrumentation, number
plate light)
Increase stabilized output current by paralleling drivers
Nexperia
NCR320U / NCR321U
250 mA LED driver in SOT457
1.4. Quick reference data
Table 2. Quick reference data
Symbol
Parameter
V
EN
enable voltage
NCR320U
NCR321U
V
out
I
out
output voltage
stabilized output current
NCR320U
NCR321U
[1]
Pulse test: t
p
≤ 300 µs; δ ≤ 0.02
Conditions
Min
-
-
-
Typ
-
-
-
10
10
Max
25
4.5
16
11
11
Unit
V
V
V
mA
mA
V
out
= 1.4 V;
V
EN
= 12 V
V
out
= 1.4 V;
V
EN
= 3.3 V
[1]
9
[1]
9
2. Pinning information
Table 3. Pinning
Pin
Symbol
1
2
3
4
5
6
VEN
IOUT
IOUT
GND
IOUT
REXT
Description
enable voltage
output current
output current
ground
output current
external resistor
1
2
3
Simplified outline
6
5
4
Symbol
REXT
IOUT
GND
SC-74; TSOP6
(SOT457)
VEN
IOUT
IOUT
aaa-029361
3. Ordering information
Table 4. Ordering information
Type number Package
Name
NCR320U
NCR321U
SC-74; TSOP6
SC-74; TSOP6
Description
plastic surface-mounted package; 6 leads
plastic surface-mounted package; 6 leads
Version
SOT457
SOT457
4. Marking
Table 5. Marking codes
Type number
NCR320U
NCR321U
Marking code
L4
L5
NCR320U_NCR321U
All information provided in this document is subject to legal disclaimers.
©
Nexperia B.V. 2018. All rights reserved
Product data sheet
Rev. 1 — 11 December 2018
2 / 17
Nexperia
NCR320U / NCR321U
250 mA LED driver in SOT457
5. Limiting values
Table 6. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol
I
out
V
EN
Parameter
stabilized output current if
external resistor is used
enable voltage
NCR320U
NCR321U
V
out
V
R
P
tot
output voltage
reverse voltage
total power dissipation
T
amb
≤ 25 °C
-
-
-
[1]
-
[2]
-
[3]
-
[4]
-
[5]
-
T
j
T
amb
T
stg
[1]
[2]
[3]
[4]
[5]
Conditions
Min
-
Max
300
Unit
mA
25
4.5
16
0.5
475
650
750
1100
150
150
150
V
V
V
V
mW
mW
mW
mW
°C
°C
°C
junction temperature
ambient temperature
storage temperature
-
-55
-65
Between all terminals.
Device mounted on an FR4 Printed-Circuit Board (PCB), single-side copper (35 µm), tin-plated and
standard footprint.
Device mounted on an FR4 Printed-Circuit Board (PCB), single-side copper (35 µm), tin-plated; mounting
2
pad for collector 1 cm .
Device mounted on an FR4 Printed-Circuit Board (PCB), 4-layer copper, tin-plated and standard footprint.
Device mounted on an FR4 Printed-Circuit Board (PCB), 4-layer copper, tin-plated; mounting pad for
2
collector 1 cm .
1.2
P
tot
(W)
0.9
(2)
(3)
aaa-029389
(1)
0.6
(4)
0.3
0
-75
-25
25
2
75
125
175
T
amb
(°C)
(1) FR4 PCB, 4-layer copper, 1 cm
(2) FR4 PCB, 4-layer copper, standard footprint
2
(3) FR4 PCB, single sided copper (35 µm), 1 cm
(4) FR4 PCB, single-sided copper (35 µm), standard footprint
Fig. 1.
Power derating curve
NCR320U_NCR321U
All information provided in this document is subject to legal disclaimers.
©
Nexperia B.V. 2018. All rights reserved
Product data sheet
Rev. 1 — 11 December 2018
3 / 17
Nexperia
NCR320U / NCR321U
250 mA LED driver in SOT457
6. Thermal characteristics
Table 7. Thermal characteristics
Symbol Parameter
R
th(j-a)
thermal resistance from
junction to ambient
Conditions
in free air
Min
[1]
-
[2]
-
[3]
-
[4]
-
R
th(j-sp)
[1]
[2]
[3]
[4]
10
3
Z
th(j-a)
(K/W)
10
2
Typ
-
-
-
-
-
Max
265
190
165
115
50
Unit
K/W
K/W
K/W
K/W
K/W
thermal resistance from
junction to solder point
-
Device mounted on an FR4 PCB, single-sided copper (35 µm), tin-plated and standard footprint.
Device mounted on an FR4 PCB, single-sided copper (35 µm), tin-plated; mounting pad
2
for collector 1 cm .
Device mounted on an FR4 PCB, 4-layer copper, tin-plated and standard footprint.
2
Device mounted on an FR4 PCB, 4-layer copper, tin-plated; mounting pad for collector 1 cm .
aaa-010054
duty cycle = 1
0.75
0.5
0.33
0.2
0.1
10
0.05
0.02
0.01
0
1
10
-5
10
-4
10
-3
10
-2
10
-1
1
10
10
2
t
p
(s)
10
3
FR4 PCB; single-sided copper; tin-plated and standard footprint
Fig. 2.
Transient thermal impedance from junction to ambient as a function of pulse duration; typical values
10
3
Z
th(j-a)
(K/W)
10
2
duty cycle = 1
0.75
0.5
0.33
0.2
0.1
10
0.05
0.02
0.01
1
10
-5
0
10
-4
10
-3
10
-2
10
-1
1
10
10
2
t
p
(s)
10
3
aaa-010055
FR4 PCB; 4-layer copper; tin-plated and standard footprint
Fig. 3.
Transient thermal impedance from junction to ambient as a function of pulse duration; typical values
NCR320U_NCR321U
All information provided in this document is subject to legal disclaimers.
©
Nexperia B.V. 2018. All rights reserved
Product data sheet
Rev. 1 — 11 December 2018
4 / 17
Nexperia
NCR320U / NCR321U
250 mA LED driver in SOT457
7. Characteristics
Table 8. Characteristics
T
amb
= 25 °C unless otherwise specified.
Symbol
V
(BR)CEO
h
FE
R
int
V
Rint
I
EN
Parameter
collector-emitter
breakdown voltage
DC current gain
internal resistor
voltage drop at internal
resistor R
int
enable current
NCR320U
NCR321U
R
B
bias resistor
NCR320U
NCR321U
I
out
stabilized output current
NCR320U
NCR321U
I
out
stabilized output current
NCR320U at R
ext
= 3 Ω
NCR321U at R
ext
= 3 Ω
V
out, min
lowest sufficient output
voltage overhead:
V
out
= V
CC
- V
LED
NCR320U
NCR321U
ΔI
out
/(I
out
x ΔV
CC
)
NCR320U
NCR321U
[1]
Pulse test: t
p
≤ 300 μs; δ ≤ 0.02.
Conditions
I
C
= 1 mA; I
B
= 0 A
V
CE
=1 V; I
C
= 50 mA
I
Rint
= 10 mA
I
out
= 10 mA
Min
16
[1]
200
85
[1]
0.85
Typ
-
350
95
0.95
Max
-
-
105
1.05
Unit
V
Ω
V
V
EN
= 12 V
V
EN
=3.3 V
[1]
-
[1]
-
-
-
1.2
1.2
10
1.5
10
10
250
250
1.4
-
-
-
-
11
11
-
-
-
mA
mA
kΩ
kΩ
mA
mA
mA
mA
V
V
EN
= 12 V; V
out
= 1.4 V
V
EN
= 3.3 V; V
out
= 1.4 V
V
EN
= 12 V; V
out
> 1.4 V
V
EN
= 3.3 V; V
out
> 1.4 V
I
out
> 10 mA
[1]
9
[1]
9
[1]
-
[1]
-
-
ΔI
out
/(I
out
x ΔT
amb
)
stabilized output current change over ambient temperature
V
EN
= 12 V; V
out
> 2 V
V
EN
= 3.3 V; V
out
> 2 V
V
EN
= 12 V; V
out
> 2 V
V
EN
= 3.3 V; V
out
> 2 V
[1]
-
[1]
-
[1]
-
[1]
-
-0.27
-0.27
1
1
-
-
-
-
%/K
%/K
%/V
%/V
stabilized output current change over supply voltage
NCR320U_NCR321U
All information provided in this document is subject to legal disclaimers.
©
Nexperia B.V. 2018. All rights reserved
Product data sheet
Rev. 1 — 11 December 2018
5 / 17