NJW4616
Constant Current LED Driver with PWM Dimming Control
■
GENERAL DESCRIPTION
The NJW4616 is a constant current LED driver with PWM
dimming control. The output current can be set by external
sensing resister, and the NJW4616 can set up to 300mA.
Because the withstand voltage of the output (LED) pin is 40V, it
can series-connect the LED depending on forward voltage of the
LED.
The LED dimming control can be regulated via PWM duty cycle.
It is suitable for back light, light source and so on.
■
PACKAGE OUTLINE
NJW4616U2
(SOT-89-5)
■
FEATURES
▪
Supply Voltage Range
2.5V to 40V
▪
Output Voltage
V
LED
=40V max.
▪
Output Current
I
LED
=20mA to 300mA
▪
Output Current Accuracy
1.5%
▪
To 11 of White LED can be operated. (at LED Vf=3.4V)
▪
Quiescent Current
450µA max.
▪
PWM Dimming Control and Enable Control (Common Pin)
▪
Over Current Protection
▪
Thermal Shutdown Protection
▪
LED Short Protection
▪
Package
SOT-89-5
■
BLOCK DIAGRAM
V
DD
LED
+
V
REF
(0.2V)
R
S
Current Limit
Thermal Shut Down
LED Short Protection
Standby Timer
Control
Logic
GND
EN/PWM
Ver.2020-06-15
-1-
NJW4616
■
PIN CONFIGURATION
5. V
DD
1. EN/PWM
2. GND
2. GND
3. R
S
4. LED
■
PIN DESCRIPTIONS
Pin No.
Pin Name
I/O
Function
Standby control pin and PWM signal input pin for dimming control.
[At Standby control]
Normal operation: High Level.
Standby mode: Low Level.
[At PWM signal input]
The LED dimming control can be regulated by PWM duty cycle.
In the case without dimming, I
LED
becomes the current set by the external resistor
(Rs) when High level is input to this pin.
Note that this pin should not be open.
Ground pin
Resistor connect pin of I
LED
setting.
The LED current can be set with connected resistor (R
S
) between R
S
pin and GND
pin. R
S
[Ω] = 0.2 [V] / I
LED
[A]
Constant current circuit output pin
Connect cathode pin of LED.
Power Supply pin
1
EN/PWM
I
2
3
4
5
GND
R
S
LED
V
DD
-
O
O
-
-2-
Ver.2020-06-15
NJW4616
■
ABSOLUTE MAXIMUM RATINGS
PARAMETER
Supply Voltage
Output Voltage
EN/PWM Pin Voltage
Power Dissipation
Junction Temperature Range
Operating Temperature Range
Storage Temperature Range
SYMBOL
V
DD
V
LED
V
ENPWM
P
D
T
j
T
opr
T
stg
RATINGS
-0.3 to +45
-0.3 to +45
-0.3 to +45
625 (*1)
2400 (*2)
-40 to +150
-40 to +125
-50 to +150
(Ta = 25C)
UNIT
V
V
V
mW
C
C
C
2
(*1) Mounted on glass epoxy board. (76.2 × 114.3 × 1.6mm: based on EIA/JEDEC standard size, 2Layers, Cu area 100mm )
(*2) Mounted on glass epoxy board. (76.2 × 114.3 × 1.6mm: based on EIA/JEDEC standard, 4Layers),
(For 4Layers: Applying 74.2 × 74.2mm inner Cu area and a thermal via hole to a board based on JEDEC standard JESD51-5)
■
RECOMMENDED OPERATING CONDITIONS
PARAMETER
SYMBOL
Supply Voltage
V
DD
Output Current
I
LED
Output Voltage
V
LED
TEST CONDITIONS
MIN.
2.5
20
-
TYP.
-
-
-
MAX.
40
300
40
UNIT
V
mA
V
■
ELECTRICAL CHARACTERISTICS
(Unless otherwise noted, V
DD
= 12V, V
LED
= 1V, R
S
= 2Ω, V
ENPWM
= V
DD
, Ta = 25C)
PARAMETER
SYMBOL
TEST CONDITIONS
MIN.
TYP.
MAX. UNIT
Quiescent Current
I
DD
-
330
450
µA
Quiescent Current at OFF State
I
DD_OFF
V
ENPWM
= GND
-
-
0.1
µA
Output Current Accuracy
-1.5
-
+1.5
%
I
LED
Output (LED) Pin Leak Current
OFF Delay Time
EN/PWM Pin ON Voltage1
EN/PWM Pin ON Voltage2
EN/PWM Pin OFF Voltage
EN/PWM Pin Input Current
R
S
Pin Output Current
PWM Dimming ON Delay Time
PWM Dimming OFF Delay Time
LED Short Protection
Detect Voltage
Maximum Output Current
I
LEAK
t
D_OFF
V
ENPWM_ON
1
V
ENPWM_ON
2
V
ENPWM_OFF
I
ENPWM
I
OUT_RS
t
PWM_ON
t
PWM_OFF
V
LED_SHORT
I
LED_MAX
R
S
= 0Ω
V
DD
<5V, I
LED
= OFFON
V
DD
≥5V,
I
LED
= OFFON
I
LED
= ONOFF
LED = OPEN
R
S
= 0.62Ω, V
ENPWM
= L
H
R
S
= 0.62Ω, V
ENPWM
= H
L
V
ENPWM
= GND,
V
DD
= V
LED
= 40V
-
10
-
25
-
-
-
7
4
10
1
21
550
0.1
45
V
DD
V
DD
0.5
-
-
-
-
24
µA
ms
V
V
V
µA
µA
µs
µs
V
mA
0.7V
DD
3.5
0
-
-
-
-
18
300
-
Ver.2020-06-15
-3-
NJW4616
■
TYPICAL APPLICATION
V
DD
/ V
+
(*3)
V
DD
LED
I
LED
+
V
REF
(0.2V)
I
LED
0
Output Current Wave Form
at PWM Dimming
R
S
Current Limit
Thermal Shut Down
LED Short Protection
Control
Logic
R
S
: Current Sense Resistor
H : ON
L : OFF
PWM : Dimming
Control
Standby Timer
GND
EN/PWM
The R
s
Resistance Setting formula:
R
S
(
)
½
0
.
2
(
V
)
I
LED
(
A
)
(*3) If the wiring from the power supply to the LED anode pin is long, the voltage may change due to the influence of the
parasitic elements.
As the countermeasure, it should connect a decoupling capacitor as close to the LED as possible.
-4-
Ver.2020-06-15
NJW4616
■
TYPICAL CHARACTERISTICS
Quiescent Current vs. Supply Voltage
450
400
[V
LED
=1V, V
ENPWM
=V
DD
, R
S
=2Ω]
Quiescent Current vs. Temperature
[V
DD
=12V, V
LED
=1V, V
ENPWM
=V
DD
, R
S
=2Ω]
450
400
Quiescent Current : I
DD
[μA]
Quiescent Current : I
DD
[μA]
350
300
250
200
150
100
50
0
0
10
20
30
Supply Voltage : V
DD
[V]
40
-40℃
25℃
125℃
150℃
350
300
250
200
150
100
50
0
-50
-25
0
25 50 75 100 125 150
Temperature : [ºC]
Quiescent Current at OFF State vs. Temperature
Quiescent Current at OFF State : I
DD_OFF
[nA]
100
[V
LED
=1V, V
ENPWM
=GND, R
S
=2Ω]
VDD=2.5V
VDD=12V
10
VDD=40V
1
0.1
-50
-25
0
25 50 75 100 125 150
Temperature : [ºC]
Output Pin Leak Current vs. Temperature
1000
[V
DD
=40V, V
LED
=40V, V
ENPWM
=GND, R
S
=2Ω]
VLED=1V
OFF Delay Time vs. Temperature
45
40
OFF Delay Time : t
D_OFF
[ms]
[V
DD
=12V, V
LED
=1V]
Output Pin Leak Current : I
LEAK
[nA]
VLED=5V
VLED=40V
100
35
30
25
20
15
10
5
10
1
0.1
-50
-25
0
25 50 75 100 125 150
Temperature : [ºC]
0
-50
-25
0
25 50 75 100 125 150
Temperature : [ºC]
Ver.2020-06-15
-5-
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