PIN DESCRIPTION
PIN NUMBER
PIN NAME
DESCRIPTION
1
VIN
Input Voltage for the charge pump. Decouple with 1µF ceramic
capacitor close to the pins of the IC.
2
3
4
C1
C2
Positive input for the external fly capacitor. Connect a ceramic 1µF
capacitor close to the pins of the IC.
Negative input for the external fly capacitor. Connect a ceramic 1µF
capacitor close to the pins of the IC.
FLASH
Logic input to toggle operation between FLASH and TORCH mode.
In TORCH mode FB is regulated to the internal 50mV reference. In
FLASH mode FB reference voltage can be adjusted by changing the
resistor from RSET pin to ground. Choose the external current sense
resistor (RSENSE) based on desired current in TORCH mode. The
FLASH mode should be limited to 200ms to avoid overheating the
charge pump.
5
6
EN
Shutdown control input. Connect to VIN for normal operation, connect
to ground for shutdown.
RSET
Connect a resistor from this pin to ground. When in FLASH mode
(FLASH = High) this resistor sets the current regulation point
according to the following: VFB = (1.26V/ RSET)*11.2KΩ.
7
FB
Feedback input for the current control loop. Connect directly to the
current sense resistor.
8
9
SGND
PGND
VOUT
Internal ground pin. Control circuitry returns current to this pin.
Power ground pin. Fly capacitor current returns through this pin.
10
Charge Pump Output Voltage. Decouple with an external capacitor.
At least 1uF is recommended. Higher capacitor values reduce output
ripple.
Date: 12/15/04
SP6685 Charge Pump LED Driver for Camera Flash
© Copyright 2004 Sipex Corporation
3
SIPEX [ SIPEX CORPORATION ]
