3 channel LED driver with Charge Pump
AK7864A includes the charge pump power supply and the 3 channel LED driver who drives the LED of the anode
common in the constant current. The current to pass for each channel can be adjusted by the external resistance and
the register setting. Also, it has the control pins which turn on or off the current. It is the suitable for the LED drive
for the CIS sensor.
■ Operating Temperature Range 0 ~ 70°C
■ LED Driver Current
- RED: 66mA
- GREEN: 66mA
- BLUE: 66mA
The LED current is adjustable from 22mA to 66mA by the external resistor. In addition, the LED current
can be reduced to 100%~12.5% by the register. Allowable maximum Vf of the LED is 4.8V.
The 1/16 watt type is usable to external resistor.
- 3 chnnel independently ON/OFF (50% setting is an upper bound when 3ch becoming turning on at the same time)
- Current setting in eight steps
When the external resistance value becomes the assumption outside, a internal protection circuit restricts the
LED current equal to or less than 150mA (-30%~+45%)
■ Current Accuracy ±9.1%（by ideal resistance）
■ LED Current Rise / Fall iime 10μs (typ.) (10% ~ 90%)
■ Charge Pump Pressor Circuit Generate the necessary voltage for the LED （Vf max 4.8V）
■ Package 16pin QFN 3mm × 3mm, 0.75mm thickness with radiation TAB in solderside
■ Power Supply VDD 3.135 ~ 3.465V
■ Application A light source driver for CIS module of MFP