RT6238A/B
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
AGND
Analog GND.
Feedback Voltage Input. It is used to regulate the output of the converter to a set
value via an external resistive voltage divider. The feedback reference voltage is
0.7V typically.
2
FB
Internal Regulator Output. Connect a 1F capacitor to GND to stabilize output
voltage.
3
4
PVCC
PGOOD
Power Good Indicator Open-Drain Output.
Bootstrap Supply for High-Side Gate Driver. This capacitor is needed to drive the
power switch's gate above the supply voltage. It is connected between the SW and
BOOT pins to form a floating supply across the power switch driver. A 0.1F
capacitor is recommended for use.
5
BOOT
6
SW
VIN
Switch Node. Connect this pin to an external L-C filter.
Power Input. The input voltage range is from 4.5V to 18V. Must bypass with a
suitably large (10F x 2) ceramic capacitor.
7, 8
9, 10, 11, 12 GND
Ground.
Enable Control Input. A logic-high enables the converter; a logic-low forces the IC
into shutdown mode reducing the supply current to less than 10A. The EN pin
can be connected to VIN with a 100k pull-up resistor for automatic start-up. The
pull-up resistance should not small than 60k to prevent EN pin voltage over than
absolute maximum rating.
13
14
EN
SS
Soft-Start Time Setting. An external capacitor should be connected between this
pin and GND.
Function Block Diagram
PVCC
BOOT
V
IN
PVCC
Reg
Min.
Off
PVCC
VIN
VIBIAS
V
REF
UGATE
LGATE
Control
Driver
SW
OC
UV & OV
PVCC
GND
GND SW
Ripple
Gen.
SW
Comparator
PGOOD
6µA
0.9 V
+
-
REF
+
SS
FB
+
FB
-
V
IN
-
+
0.4
On-Time SW
Comparator
5k
-
EN
+
3V
1.2/1.01
Copyright 2017 Richtek Technology Corporation. All rights reserved.
©
is a registered trademark of Richtek Technology Corporation.
DS6238A/B-08 July 2017
www.richtek.com
3
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
