RT7272B
Pin Configurations
(TOP VIEW)
SW
BOOT
EN
GND
2
3
4
8
7
Marking Information
RT7272BGSP : Product Number
VIN
RLIM
COMP
FB
RT7272B
GSPYMDNN
YMDNN : Date Code
GND
9
6
5
SOP-8 (Exposed Pad)
Functional Pin Description
Pin No.
1
2
3
4,
9 (Exposed Pad)
5
Pin Name
SW
BOOT
EN
GND
FB
Pin Function
Switch Node Connect to external L-C filter.
Bootstrap Supply for High Side Gate Drive. A 100nF or greater capacitor is
recommended to connect from BOOT pin to SW pin.
Enable Control Input. A logic-high enables the converter; a logic-low forces the
device into shutdown mode.
Ground. The exposed pad must be soldered to a large PCB and connected to
GND for maximum thermal dissipation.
Feedback Input. This pin is connected to the converter output. It is used to set
the output of the converter to regulate to the desired value via an resistive
divider.
Compensation Node. 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.
Current Limit Setting. Connect to a resistor to determine current limit.
Power Input. The input voltage range is from 4.5V to 36V. Must bypass with a
suitable large ceramic capacitor.
6
7
8
COMP
RLIM
VIN
Function Block Diagram
VIN
Internal
Regulator
Shutdown
V
A
V
CC
Comparator
1.2V
+
-
Lockout
Comparator
-
1.7V
+
V
CC
Oscillator
Foldback
Control
0.4V
+
UV
S
+
R
-
Current
Comparator
Q
Q
150mΩ
SW
80mΩ
GND
Slope Comp
Current Sense
Amplifier
+
-
R
SENSE
V
A
BOOT
5kΩ
EN
-
UV
Comparator
V
CC
0.8V
+
+EA
-
SS
RLIM
FB
COMP
is a registered trademark of Richtek Technology Corporation.
Copyright
©
2013 Richtek Technology Corporation. All rights reserved.
www.richtek.com
2
DS7272B-01 January 2013
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
