XRP7657
2A, 25V Non Synchronous PWM Step Down Regulator
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only and functional operation of
the device at these ratings or any other above those
indicated in the operation sections of the specifications
below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may affect
reliability.
VIN ............................................................ -0.3V to 30V
COMP, FB pin voltage....................................-0.3V to 6V
SW, EN pin voltage ...................................... -0.3V to VIN
Storage Temperature .............................. -65°C to 150°C
Power Dissipation ................................ Internally Limited
Junction Temperature TJ ....................................... 150°C
Lead Temperature (Soldering, 10 sec) ................... 260°C
ESD Rating (HBM - Human Body Model) .................... 2kV
OPERATING RATINGS
Input Voltage Range VIN.............................. 4.75V to 25V
Output Voltage Range VOUT ............................0.8V to 21V
Junction Temperature TJ Range.................-40°C to 125°C
Thermal Resistance θJA
(junction to ambient, no heat sink, free air) ........100°C/W
ELECTRICAL SPECIFICATIONS
Specifications with standard type are for an Ambient Temperature of TA = 25°C only; limits applying over the full Operating
Junction Temperature range are denoted by a “•”. Minimum and Maximum limits are guaranteed through test, design, or
statistical correlation. Typical values represent the most likely parametric norm at TA = 25°C, and are provided for reference
purposes only. Unless otherwise indicated, VIN = 12V, VOUT = 5V, TA= 25°C.
Parameter
Input Voltage VIN
Shutdown Quiescent Current
ISHDN
Quiescent Current IQ
Feedback Voltage VFB
Feedback Bias Current IFB
Switch Current Limit ILIM
Oscillator Frequency fOSC
Oscillator Frequency fOSC1
www.DataSheet4U.com
Error Amplifier Voltage Gain GV
Error Amplifier
Transconductance GS
EN Pin Threshold High VH
EN Pin Threshold Low VL
EN Pin Input Leakage Current IEN
Internal PMOS ON Resistance
RDS(ON)
Maximum Duty Cycle DMAX
Thermal Shutdown TOTSD
Thermal Shutdown Hysteresis
THYS
Min.
4.75
0.784
2.5
336
1.5
Typ.
44
1.3
0.800
-0.1
3.4
420
40
1000
700
-5
130
155
20
Max.
25
60
2
0.816
-0.5
504
0.7
-10
150
100
Units
µA
mA
V
µA
A
kHz
kHz
V/V
µA/V
V
V
µA
mΩ
%
°C
°C
Conditions
VEN=0.4V
VEN=2.0V, VFB=1.3V
VIN=5V to 25V
VFB=1.3V
VFB=0.52V, Current limit activated or
short circuit protection mode
VEN=2.5V
VIN= VEN=12V, VFB=0.65V, IOUT=12A
VFB=0.65V, ISW=0.1A
© 2009 Exar Corporation
2/11
Rev. 1.0.0
