RT9204_07 Datasheet, PDF (4/14 Pages) Richtek Technology Corporation – Dual Regulators - Standard Buck PWM DC-DC and Linear Controller

RT9204/A
Preliminary
Functional Pin Description
GND (Pin 1)
Signal and power ground for the IC. All voltage levels are
measured with respect to this pin.
Connect UGATE pin to the PWM converter's upper
MOSFET gate. This pin provides the gate drive for the
upper MOSFET.
VCC (Pin 2)
This is the main bias supply for the RT9204/A. This pin
also provides the gate bias charge for the lower MOSFETs
gate. The voltage at this pin monitored for power-on reset
(POR) purpose. This pin is also the internal 6.0V regulator
output powered from BOOT pin when BOOT pin is directly
powered from ATX 12V.
DRV (Pin 3)
This pin is linear regulator output driver. Connect to external
bypass NPN transistor base or NMOSFET gate terminal.
FBL (Pin 4)
This pin is connected to the linear regulator output divider.
This pin also connects to internal linear regulator error
amplifier inverting input and protection monitor.
FB (Pin 5)
This pin is connected to the PWM converter's output divider.
This pin also connects to internal PWM error amplifier
inverting input and protection monitor.
SD (Pin 6)
Active low design with a 40µA pull low current source.
Pull this pin to VCC to shutdown both PWM and linear
regulator.
BOOT (Pin 7)
This pin provides ground referenced bias voltage to the
upper MOSFET driver. A bootstrap circuit is used to create
a voltage suitable to drive a logic-level N-Channel
MOSFET when operating at a single 5V power supply.
This pin also could be powered from ATX 12V, in this
situation, an internal 6.0V regulator will supply to VCC
pin for internal voltage bias.
UGATE (Pin 8)
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DS9204/A-08 March 2007