SP7612 SP7614
Low Dropout Linear LED Driver
FEATURES
LED Drivers for parallel connected LEDs
No EMI, no switching noise
Integrated current matching
PWM and Analog brightness control
Enable/Shutdown control
Shutdown current < 0.01µA
Tiny, RoHS Compliant Lead-Free
Packages: SC-70
N/C
VLED1
CTRL
3
2
1
SP7614A
SP7614
6 Pin SC70
4
GND
5
VLED2
6
ON/OFF
Pin outs for SP7611A and SP7612A on page 3
Part #
SP7612
SP7614
Channels
3
2
Maximum Steady
State Current per LED
40mA
80mA
APPLICATIONS
Ultra low cost Handsets
PDA, DSC, MP3 players
Handheld Computers
LCD Display Modules
Keyboard Backlight
LCD Backlight
DESCRIPTION
The SP7612/4 provides a simple solution for a matched current source for any color LED. The current in the
LEDs can be programmed by an external resistor. The SP7612 is capable of driving three LEDs, while the
SP7614 can drive two LEDs. LED1 should always be connected to an LED and never left open in order to
have the other LEDs driven with a matched current to LED1. The SP7612 and SP7614 feature Enable pins
for flexible on/off control and PWM dimming. SP7612/4 has extremely low (0.01uA typical) shutdown current,
prolonging the battery life and giving the longest standby period possible in today's modern design. It is
available in a small footprint 6-pin SC-70 package.
TYPICAL APPLICATION SCHEMATIC
SP7612 Typical application
Jan 09 -08 RevT
SP7612/7614 Low Dropout Linear LED driver
Page 1
©
2008 EXAR Corporation
SP7612 SP7614
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation
sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect
reliability.
V
LED1
, V
LED2
, V
LED3,
V
LED4
and ENABLE Voltage to GND............................................................................... -0.3V to 6V
CTRL Voltage to GND . ..................................................................................................................................... .-0.5V
Output Current (I
OUT
) (SP7612)……………....................................................................................................... 40mA
Output Current (I
OUT
) (SP7614)…..................................................................................................................... 80mA
Power Dissipation per Package - 6-pin SC-70 at T
A
=85°C.............................................................................. 190mW
Junction Temperature ...................................................................................................................................... +150°C
Storage Temperature.......................................................................................................................... -55°C to +150°C
ESD Level.
.......................................................................................................................................................................................................
4kV HBM
ESD Level.
.......................................................................................................................................................................................................
1kV CDM
ELECTRICAL SPECIFICATIONS
Specifications are at T
A
=25°C, V
IN
= 3.3 to 5.5, ENABLE =V
IN
,
♦
denotes the specifications which apply over the
full operating temperature range, unless otherwise specified.
PARAMETER
LED Cathode Voltage
(V
LED
)
Ambient Temperature
Output Current
Multiplication Ratio in
Linear Region (Note1)
Output Current
Multiplication Ratio in
Saturation (Note1)
LED to LED Current
Matching
Current in OFF Mode
Min. ENABLE ""ON
Voltage" (Note 2)
Max. ENABLE ""OFF
Voltage" (Note 2)
-40
SP7612
140
SP7614
SP7612
SP7614
365
730
-3
435
870
0.8
0.01
3
0.5
505
1010
3
1
%
µA
V
V
200
260
PART #
MIN
TYP
MAX
5.5
85
UNITS
♦
V
ºC
CONDITIONS
See graph for LED
Current vs. Cathode
Voltage
I
SET
= 100µA
V
LED
= 300mV
I
SET
= 100µA
V
LED
= 150mV
I
SET
= 25µA
V
LED
= 0.5V
♦
♦
♦
♦
I
SET
= 100µA
V
LED
= 300mV
V
ENABLE
= 0.0V
I
SET
= 150µA
Note 1: Output current Multiplication Ratio (I
LED
/I
SET
) is not linear. For actual ratio and I
LED
please refer to typical
performance characteristics on pages 4 through 7.
Note 2: ENABLE "ON" is V
ON/OFF
where I
LED1
> 20mA @ V
LED1
= 0.3V.
ENABLE "OFF" is V where
I
< 1μA @ V > 0.3V.
Jan 09 -08 RevT
SP7612/7614 Low Dropout Linear LED driver
Page 2
©
2008 EXAR Corporation
SP7612 SP7614
PIN DESCRIPTION
SC70 Package
Pin #
1
2
3
4
5
6
SP7612
CTRL
LED2
LED1
GND
LED3
ENABLE
Pin Name
SP7614
CTRL
LED1
NC
GND
LED2
ENABLE
DESCRIPTION
Sets L E D Current
Connect to Cathode of L E D
Connect to Cathode of L E D
Ground
Connect to Cathode of L E D
Chip ON/ OFF Disable
PINOUTS
Jan 09 -08 RevT
SP7612/7614 Low Dropout Linear LED driver
Page 3
©
2008 EXAR Corporation
SP7612 SP7614
SP7612 TYPICAL PERFORMANCE CHARACTERISTICS
LED current vs Rset for LED voltage (Vcathode)
Vcontrol set to 3V
LED current vs Cathode voltage (VLED)
Jan 09 -08 RevT
SP7612/7614 Low Dropout Linear LED driver
Page 4
©
2008 EXAR Corporation
SP7612 SP7614
SP7612 TYPICAL PERFORMANCE CHARACTERISTICS
Iset vs Control pin voltage
LED current vs Enable voltage
Iset at .5V VLED(cathode voltage)
Jan 09 -08 RevT
SP7612/7614 Low Dropout Linear LED driver
Page 5
©
2008 EXAR Corporation