34704_09 Datasheet, PDF (18/49 Pages) Freescale Semiconductor, Inc – Multiple Channel DC-DC Power Management IC

FUNCTIONAL DESCRIPTION
FUNCTIONAL PIN DESCRIPTION
REG1 REGULATED OUTPUT VOLTAGE PIN
(VOUT1) (34704A ONLY)
Connect this pin directly to the load directly and to the
output filter as close to the pin as possible.
REG1 BOOTSTRAP CAPACITOR INPUT PIN (BT1)
Connect a 1μF capacitor between this pin and SW1 pin to
enhance the gate of the Switch Power MOSFET.
I²C SERIAL INTERFACE CLOCK INPUT (SCL)
I²C serial interface clock input.
I²C SERIAL INTERFACE DATA INPUT (SDA)
I²C serial interface data input
POWER RESET OUTPUT SIGNAL
(MICROPROCESSOR RESET) (RST)
This is an open drain output and must be pulled up by an
external resistor to a supply voltage like V_IN.
REG7 COMPENSATION NETWORK CONNECTION
(COMP7)
REG7 compensation network connection.
REG7 RESISTOR FEEDBACK NETWORK
REFERENCE VOLTAGE (VREF7) (34704A ONLY)
Connect this pin to the bottom of the feedback resistor
divider.
REG7 VOLTAGE FEEDBACK INPUT FOR
VOLTAGE REGULATION/PROGRAMMING (FB7)
(34704A ONLY)
Connect the feedback resistor divider to this pin.
REG7 EXTERNAL POWER MOSFET GATE DRIVE
(DRV7) (34704A ONLY)
REG7 external Power MOSFET gate drive.
REG7 OUTPUT VOLTAGE RETURN PIN (VOUT7)
(34704A ONLY)
This is the discharge path of REG7 output voltage.
REG6 VOLTAGE FEEDBACK INPUT FOR
VOLTAGE REGULATION/PROGRAMMING (FB6)
(34704A ONLY)
Connect the feedback resistor divider to this pin.
REG6 BOOTSTRAP CAPACITOR INPUT PIN (BT6)
(34704A ONLY)
Connect a 0.01μF capacitor between this pin and SW6 pin
to enhance the gate of the Synchronous Power MOSFET.
REG6 SWITCHING NODE (SW6) (34704A ONLY)
The inductor is connected between this pin and the VIN
pin.
REG6 REGULATED OUTPUT VOLTAGE PIN
(VOUT6) (34704A ONLY)
Connect this pin directly to the load directly and to the
output filter as close to the pin as possible.
ANALOG GROUND (AGND)
Analog ground of the IC.
BATTERY VOLTAGE CONNECTION (VIN)
Input decoupling /filtering is required for the device to
operate properly.
INTERNAL SUPPLY VOLTAGE (VDDI)
Connect a 1μF low ESR decoupling filter capacitor
between this pin and GND.
BATTERY DETECTION (LION)
Pull this pin high to VIN to indicate a connection to a Li-Ion
battery.
DUAL FUNCTION IC TURN ON/OFF (ONOFF)
This is a hardware enable/disable for the 34704. It can be
connected to a mechanical switch to turn the power On or Off.
REG2 BOOST STAGE BOOTSTRAP CAPACITOR
INPUT PIN (BT2U)
Connect a 1μF capacitor between this pin and SW2U pin
to enhance the gate of the Switch Power MOSFET.
REG2 COMPENSATION NETWORK CONNECTION
(COMP2)
REG2 compensation network connection.
REG2 VOLTAGE FEEDBACK INPUT FOR
VOLTAGE REGULATION/PROGRAMMING (FB2)
Connect the feedback resistor divider to this pin.
REG2 BUCK STAGE BOOTSTRAP CAPACITOR
INPUT PIN (BT2D)
Connect a 1μF capacitor between this pin and SW2D pin
to enhance the gate of the Switch Power MOSFET.
REG2 POWER SUPPLY INPUT VOLTAGE (PVIN2)
This is the connection to the drain of the high side switch
FET. Input decoupling /filtering is required for proper REG2
operation.
34704
18
Analog Integrated Circuit Device Data
Freescale Semiconductor