Features: · Drives up to 12 white LEDs (4 series x 3 parallels)
VSW = 18.0V(Max.), IOUT = 60mA
· Built-in PWM Dimming Control
(Selectable 8 out of 64 steps)
· Built-in Luminance Sensor Control (Power Supply for Sensor & A/D converter)
(No MPU-access required after initial setting)
· Built-in Temperature Compensation Circuit to Suppress the Characteristic Degradation of LEDs
· Uses Small Inductor and Capacitors
· 1.8V to 3.6V Operating Voltage for Logic Circuits (VDDL)
· 3.0V to 5.5V Operating Voltage for Step-up Circuits (VDD)
· CMOS Technology
· Package : QFN28 / SSOP20Pinout
Specifications
| PARAMETERS |
SYMBOL |
CONDITIONS |
RATINGS |
UNIT |
NOTE |
| VDD Power Supply |
VDD |
|
-0.3 to +6 |
V |
|
| VDDL Power Supply |
VDDL |
|
-0.3 to VDD |
V |
|
| Input Voltage |
VIN1 |
CX/TCLK, REF,
FB, SENS terminals |
-0.3 to VDD+0.3 |
V |
|
| Input Voltage |
VIN2 |
REQ, DATA, SCK, RSTb
Terminals |
-0.3 to VDD+0.3 |
V |
|
| Switch Voltage |
VSW |
SW terminal |
+18.0 |
V |
3 |
| Power Dissipation |
PD |
|
T.B.D. |
mW |
4
5 |
| Operating Temperature |
Topr |
|
-40 to +85 |
|
|
| Storage Temperature |
Tstg |
|
-55 to +125 |
|
|
NOTE1) All voltages are relative to VSS = 0V reference.
NOTE2) Do not exceed the absolute maximum ratings, otherwise the stress may cause a permanent damage to the IC. It is also recommended that the IC be used in the range specified in the DC electrical characteristics, or the electrical stress may cause mulfunctions and affect the reliability.
NOTE3) The switch voltage VSW is the highest voltage in the system. This voltage must not exceed the absolute aximum rating.
VSW =VF(LED) x N(LED) +VF(D1) +VREF
VF(LED) :Forward Voltage of LED
N(LED) :The Number of LEDs
VF(D1) :Forward Voltage of Diode D1
For instance,
when VF(LED) = 3.6V, N(LED)=4pcs, VF(D1)=0.3V, VREF=0.6V(TYP), VSW= 3.6V x 4 + 0.3V + 0.6V = 15.3V.
NOTE4) Mounted on the glass epoxy board (50mm x 50mm x 1.6mm)
NOTE5) Mounted on the board specified by EIA/JEDEC (2-layer FR-4, 76.2mm x 114.3mm x 1.6mm)
DescriptionThe NJU6052 is a white LED driver with an automatic dimming control. It contains an output driver, a PWM controller, a luminance sensor control (power supply for sensor & A/D converter), a step-up DC/DC converter, a serial interface, etc.
The output driver NJU6052 ensures a 60mA maximum capability which allows the connection of 12 white LEDs (4 series x 3 parallels). Depending on the ambient light sensed with an external luminance sensor, the PWM controller of NJU6052 controls PWM duty in 8 steps preselected out of 64 steps. In addition, the frequency of the DC/DC converter is high so that NJU6052 permits the use of small, low-profile inductors and capacitors to minimize the footprint in space-conscious applications.
All of these benefits make the NJU6052 suitable for the battery-powered portable applications such as a cellular phone, a camcorder, PDA, etc.
NJU6052 Data Sheet
