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Sipex Corporation |
www.DataSheet4U.com
Solved by
.
TM
Complete Backlight Solution
SP7680
FEATURES
Complete Backlight Solution
Separate control for 4 main, 2 sub, and keypad LEDs
Built-in 6-bit DAC for precise current setting
I2C serial interface
Data is stored in shutdown
1x and 1.5x mode operation with automatic switchover
Very low dropout: 200mV typ
Very low 31µA current (LSB)
2MHz switching frequency reduces external components
Power-saving shutdown mode of 1µA
Built-in over-temperature protection
Available in Lead Free, RoHS compliant package:
Small 16-pin 3x3 QFN
LED 6
LED 7
SDA
SCL
1
2
3
4
16 15 14 13
12 LED 1
11 GND
10 C2+
9 C2-
5678
DESCRIPTION
The SP7680 is a complete backlight display solution that is designed to independently control LEDs for
main and auxiliary displays as well as the keypad. A two line I2C serial interface allows a simple way to
adjust each current individually in order to provide ultimate flexibility in driving LEDs. The data is loaded
into internal registers upon power up and stored while in shutdown. When the chip is enabled the stored
values set the LED currents. Extra low 33µA LSB allows trickle current through the LEDs for non-
reflecting LCD displays. The SP7680 automatically detects 1x or 1.5x operation for optimal efficiency.
MAIN
SUB
TYPICAL APPLICATION CIRCUIT
AUX
VIN
VIN
2.2µF
SDA
SCL
C1
SP7680
C2
0.47µF 0.47µF
VOUT
1µF
June 21-07 revH
SP7680: Complete Backlight Solution
Page 1
2007 Sipex Corporation
www.DataSheet4U.com
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.
VIN, SDA, SCL, LEDx, VOUT.....................................-0.3V to 6.0V
Power Dissipation ……………………...………… Internally limited
Storage Temperature..………..…………………….-65°C to 150°C
Junction Temperature
(TJ = TA + PD•33.3°C/W)……………………….. 40°C to +125°C
ӨJA (1 square 1oz Cu)……………...…….………….33.3°C/W
ELECTRICAL SPECIFICATIONS
Unless otherwise specified: VIN= 2.7V-5.5V, CIN = 2.2µF, COUT = 1µF, CFL2 =0.47µF, CFL2 = 0.47µF, TA =
-40°C to +85°C, Tj=-40°C to +125°C. Bold values apply over the full operating temperature range.
PARAMETER
MIN TYP
Operating Input Voltage Range
2.7
Operating Input Current
(4 MAIN LEDs operating at 33uA
each, all other LEDs off, in 1X
mode)
300
Operating Input Current
(Charge pump in 1.5X mode with
all LEDs at 33uA each)
5
Standby mode Quiescent Current
200
Maximum Output Current (Note 1)
200
MAX
5.5
400
8
300
UNITS
CONDITIONS
V
VIN=4.0V, VLED = 3.3V
Status = 11000000
µA CNTRL = 00011110
Main=Sub=Aux=00000000
VIN = 3.0V, VLED = 3.3V
mA
Status = 11000000
CNTRL = 11111110
Main=Sub=Aux=00000001
VIn=4.0V
µA
Status = 10000000
CNTRL = 00000000
Main=Sub=Aux=00000000
mA VIN = 3.4V, VLED = 3.3V
LED Current accuracy
LED Current matching
Current DAC Resolution
Current for DAC=000000
Current for DAC=000001
Current DAC LSB DAC=00010
Current DAC LSB DAC=00010
LED Dropout Voltage (Note 2)
Maximum LED Current
Maximum LED Current
Switching Frequency
Equivalent Resistance, 1x mode
Equivalent Resistance, 1.5x mode
Control Clock Frequency
-10
-3
5
1.6
6
0
31
1
2
31.5
63
2
3
6
10
+3
50
0.2
2.4
5
10
0.4
%
%
bits
mA
µA
mA
mA
V
mA
mA
MHz
Ω
Ω
MHz
ILED = 20mA
ILED = 20mA
1x mode only
MAIN and SUB LEDs
AUX LED
ILED =20mA for MAIN and SUB;
ILED =40mA for AUX
After 63 counts MAIN and SUB
LEDs
After 63 counts AUX LED
VIN=3.4V
VIN=3.4V
June 21-07 revH
SP7680: Complete Backlight Solution
Page 2
2007 Sipex Corporation
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