rt9246a Richtek Technology Corporation, rt9246a Datasheet - Page 3

• Manufacturer Part Number: rt9246a
• Description: Multi-phase Controller Core Power Supply
• Manufacturer: Richtek Technology Corporation

Functional Pin Description
VID4 (Pin 1), VID3 (Pin 2), VID2 (Pin 3), VID1 (Pin 4),
VID0 (Pin 5)
DAC
internally pulled to 2.2V if left open.
NC (Pin 6, Pin 20, Pin 24)
No Input Connection
FBRTN (Pin 7)
V
FB (Pin 8)
Inverting input of the internal error amplifier.
COMP (Pin 9)
Output of the error amplifier and input of the PWM
comparator.
PGOOD (Pin 10)
Power good open-drain output.
DVD (Pin 11)
Programmable power UVLO
input.
DS9246A-04 March 2007
CORE
700
600
500
400
300
200
100
voltage identification inputs for K8. These pins are
differential sense return.
0
0
10
Oscillator Ferquency vs. R
20
30
R
detection or converter enable
RT
(k ◊ )
(kΩ)
40
50
RT
60
70
SS (Pin 12)
Connect this SS pin to GND with a capacitor to set the
soft-start time interval and to smooth V
VID Jump.
RT (Pin 13)
Switching frequency setting. Connect this pin to GND with
a resistor to set the frequency.
VOSS (Pin 14)
V
resistor to set the offset
IMAX (Pin 15)
Over-Current protection set.
ICOMMON (Pin 16)
Common negative input of current sense amplifiers for all
three channels.
IOUT (Pin 17)
Output current indication pin. The current through IOUT
pin is proportional to the output current.
ADJ (Pin 18)
Current sense output for active droop adjust. Connect a
resistor from this pin to GND to set the load droop.
GND (Pin 19)
IC ground.
ISP1 (Pin 23), ISP2 (Pin 22), ISP3 (Pin 21)
Current sense positive input pins for individual converter
channel current sensing.
PWM1 (Pin 27), PWM2 (Pin 26), PWM3 (Pin 25)
PWM outputs for each driven channel. Connect these pins
to the PWM input of the MOSFET driver. For systems
which use 2 channels, connect PWM3 high.
VCC (Pin 28)
IC power supply. Connect this pin to a 5V supply.
CORE
initial value offset. Connect this pin to GND with a
value.
RT9246A
CORE
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