RT8064 Datasheet, PDF (3/13 Pages) Richtek Technology Corporation – 2A, 2MHz, Synchronous Step-Down Converter

RT8064
Functional Pin Description
Pin No.
SOP-8
(Exposed Pad)
WDFN-8L 3x3
Pin Name
Pin Function
Error Amplifier Compensation Point. The current comparator
1
1
COMP threshold increases with this control voltage. Connect external
compensation elements to this pin to stabilize the control loop.
Soft-Start Control Input. Connect a capacitor from SS to GND to
2
2
SS
set the soft-start period. A 10nF capacitor sets the soft-start
period to 800μs (typ.).
3
3
EN
Enable Control Input. Float or connect this pin to logic high for
enable. Connect to GND for disable.
4
4
VIN
Power Input Supply. Decouple this pin to GND with a capacitor.
5
5
LX
Internal Power MOSFET Switches Output. Connect this pin to
the inductor.
Oscillator Resistor Input. Connect a resistor from this pin to
6
6
RT
GND sets the switching frequency. If this pin is floating, the
frequency will be set at 2MHz internally.
7
7
FB
Feedback. Receives the feedback voltage from a resistive
divider connected across the output.
8
8
PGOOD
9 (Exposed Pad) 9 (Exposed Pad) GND
Power Good Indicator. This pin is an open drain logic output that
is pulled to ground when the output voltage is not within ±12.5%
of regulation point.
Ground. The exposed pad must be soldered to a large PCB and
connected to GND for maximum power dissipation.
Function Block Diagram
RT
COMP
FB
SS
EN
SD
OSC
0.8V _EA
Output
Clamp
10µA
Hiccup
Enable
0.7V
P-G
0.4V
UV
Slope
Com
ISEN
OC
Limit
Control
Logic
OTP
Driver
NISEN
N-MOSFET I_LIM
VIN
LX
GND
PGOOD
Copyright ©2012 Richtek Technology Corporation. All rights reserved.
DS8064-07 November 2012
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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