
FUNCTIONAL DESCRIPTION
FUNCTIONAL PIN DESCRIPTION
SHUTDOWN INPUT (SD)
If this pin is tied to the GND pin, the device will be in
Shutdown mode. If left unconnected or tied to the VIN pin, the
device will be in Normal mode. The pin has an internal pull-
up of 1.5 M Ω .
REFERENCE VOLTAGE INPUT (VREFIN)
The output of channel two will track the voltage applied at
this pin.
FREQUENCY ADJUSTMENT INPUT (FREQ)
The buck converters switching frequency can be adjusted
by connecting this pin to an external resistor divider between
VDDI and GND pins. The default switching frequency (FREQ
pin connected to ground, GND) is set at 1.0 MHz.
SOFT START ADJUSTMENT INPUT (ILIM1, ILIM2)
Soft Start can be adjusted by applying a voltage between
1.25 V and VDDI on each ILIM pin.
34717
Analog Integrated Circuit Device Data
Freescale Semiconductor
13