RT7272A
Parameter
Oscillation Frequency
Short Circuit Oscillation
Frequency
Maximum Duty Cycle
Minimum On-Time
EN Input Voltage
Logic-High
Symbol
f
OSC1
f
OSC2
D
MAX
t
ON
V
IH
V
IL
V
UVLO
ΔV
UVLO
T
SD
ΔT
SD
G
CS
G
EA
ΔI
COMP
= ±10μA
V
IN
Rising
V
FB
= 0V
V
FB
= 0.7V
Test Conditions
Min
450
--
--
--
2
--
3.9
--
--
--
--
--
Typ
500
75
90
100
--
--
4.1
250
150
20
4.7
1000
Max
550
--
--
--
--
0.4
4.3
--
--
--
--
--
Unit
kHz
kHz
%
ns
V
V
mV
°C
°C
A/V
μA/V
Logic-Low
Input Under Voltage Lockout
Threshold
Input Under Voltage Lockout
Hysteresis
Thermal Shutdown
Thermal Shutdown Hysteresis
COMP to Current Sense
Transconductance
Error Amplifier Transconductance
Note 1.
Stresses beyond those listed
“Absolute
Maximum Ratings” may cause permanent damage to the device. These are
stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in
the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may
affect device reliability.
Note 2.
θ
JA
is measured at T
A
= 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7.
θ
JC
is
measured at the exposed pad of the package.
Note 3.
Devices are ESD sensitive. Handling precaution is recommended.
Note 4.
The device is not guaranteed to function outside its operating conditions.
Note 5.
R
LIM
(kΩ) = [U
OC
x 24.14 x (1 + 0.024 x (U
OC
−
3.5))
−
1.3], where U
OC
is desired upper switch peak current limit
value.
Copyright
©
2013 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS7272A-01 January 2013
www.richtek.com
5
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
