RT7273
Pin No.
10
11
12
13
14, 15
16, 17
18
19
20
21
22
23
24
25
26, 30, 31, 35,
41 (Exposed Pad)
27
28
29
32, 33, 34
36, 37
38
39
40
Pin Name
RLIM1
EN1
BOOT1
VIN1
LX1
LX2
VIN2
BOOT2
EN2
RLIM2
SS2
COMP2
FB2
LOWP
GND
PGOOD
PVCC
VCC
VINR
LX3
VIN3
BOOT3
EN3
Pin Function
Current Limit Setting for CH 1. Connect a resistor from RLIM to GND to set
the peak current limit on the output inductor.
Enable Control Input for CH 1. A low level signal on this pin disables it. If this
pin is left open, a weak internal pull-up to VCC will allow automatic enables.
Bootstrap Supply for High-Side Gate Driver of CH 1. Connect a 0.1F
ceramic capacitor from this pin to LX1.
Power Input for CH 1 and Connected to High-Side MOSFET Drain. Place a
10F ceramic capacitor close to this pin.
Switch Node of CH 1.
Switch Node of CH 2.
Power Input for CH 2. Place a 10F ceramic capacitor close to this pin.
Bootstrap Supply for High-Side Gate Driver of CH 2. Connect a 0.1F
ceramic capacitor from this pin to LX2.
Enable Control Input for CH 2. A low level signal on this pin disables it. If this
pin is left open, a weak internal pull-up to VCC will allow automatic enables.
Current Limit Setting for CH 2. Connect a resistor from RLIM2 to GND to set
the peak current limit on the output inductor.
Soft-Start Time Setting for CH 2. Connect a capacitor to this pin and GND
for soft-start time setting.
Compensation Node for CH 2. COMP is used to compensate the regulation
control loop. Connect a series RC network from COMP to GND. In some
cases, an additional capacitor from COMP to GND is required.
Feedback Voltage Input for CH 2.
Discontinuous Operation Mode Input (Active High).
Ground. The exposed pad must be connected to GND and soldered to a
large PCB copper plane for maximum power dissipation.
Power Good Indicator Output with Open-Drain.
5V Power Supply Output. Connect a capacitor 10F between this pin and
GND.
4.6V Power Supply Output. Connect a capacitor 3.3F between this pin and
GND.
Supply Voltage Input for Internal Control Circuit.
Switch Output for CH 3.
Power Input for CH 3. Place a 10F ceramic capacitor close to this pin.
Bootstrap Supply for High-Side Gate Driver of CH 3. Connect a 0.1F
ceramic capacitor from this pin to LX3.
Enable Control Input for CH 3. A low level signal on this pin disables it. If this
pin is left open, a weak internal pull-up to VCC will allow automatic enables.
Copyright
©
2014 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS7273-04
October 2014
www.richtek.com
3
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
