CM9130 Datasheet, PDF (5/12 Pages) California Micro Devices Corp – Three Output Driver for White LEDs

Functional Block Diagram
PRELIMINARY
CM9130
C1P C1N C2P C2N
VIN
Charge Pump x1, x1.5
VOUT
OSC
500 KHz
UVLO
Bandgap
ISET
Mode Select
GND
Failed LED
Condition
CM9130
Current
Sinks
LED1
LED2
LED3
EN
Pin Descriptions
PIN DESCRIPTIONS
LEAD(s)
1
2
3
NAME
LED1
C1P
VIN
DESCRIPTION
Cathode of LED1 pin.
This pin is the plus side of charge pump bucket capacitor C1. Connect a 1.0μF
ceramic capacitor with a voltage rating of 10 V or greater between C1N and C1P.
Positive supply voltage input pin. This voltage should be between 2.9V and 6V.
This pin requires a 1.0μF or larger ceramic capacitor to ground.
Enable pin and Current set pin for drivers, active low.
To set the LED current, a resistor, R_SET, is connected between this pin and ground.
The regulated LED current is 1000x the current flowing in R_SET, and is
approximately:
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ISET
I_LED
=
0----.-6---6---V------–-----(_{--L----o----g---i--c---L----o---w-----}) _{× 1000}
R_SET
If this resistor is tied to directly ground (and enable function not used) Logic Low=0,
otherwise subtract the voltage drop of the device that drives this pin low.
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06 490 N. McCarthy Blvd., Milpitas, CA 95035-5112 l Tel: [phone] l Fax: [phone] l www.cmd.com
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