Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Voltages from the indicated pins to GND
AVIN, PVIN, EN, PGOOD, SS/
TRK, COMP, FB, SW
-0.3V to +6V
Storage Temperature -65°C to 150°C
Junction Temperature 150°C
Power Dissipation (Note 2) 2.6W
Lead Temperature (Soldering,
10 sec)
260°C
Minimum ESD Rating (Note 3) ±2kV
Operating Ratings
PVIN, AVIN to GND 2.95V to 5.5V
Junction Temperature −40°C to + 125°C
Electrical Characteristics Unless otherwise stated, the following conditions apply: AVIN = PVIN = VIN = 5V.
Limits in standard type are for TJ = 25°C only, limits in bold face type apply over the junction temperature (TJ) range of -40°C to
+125°C. Minimum and Maximum limits are guaranteed through test, design, or statistical correlation. Typical values represent the
most likely parametric norm at TJ = 25°C, and are provided for reference purposes only.
Symbol Parameter Conditions Min Typ Max Unit
V
FB
Feedback pin voltage VIN = 2.95V to 5.5V 0.788 0.8 0.812 V
ΔV
OUT
/ΔI
OUT
Load Regulation I
OUT
= 100 mA to 5A 0.08 %/A
I
CL
Switch Current Limit Threshold VIN = 3.3V 6.7 7.4 8.1 A
R
DS_ON
High-Side Switch On Resistance ISW = 3.5A 36 55
mΩ
R
DS_ON
Low-Side Switch On Resistance ISW = 3.5A 32 52
mΩ
I
Q
Operating Quiescent Current Non-switching, VFB = V
COMP
3.5 6 mA
I
SD
Shutdown Quiescent current VEN = 0V 90 180 µA
V
UVLO
VIN Under Voltage Lockout Rising V
IN
2.45 2.7 2.95 V
V
UVLO_HYS
VIN Under Voltage Lockout Hysteresis Falling V
IN
45 100 mV
V
VCC
VCC Voltage I
VCC
= 0 µA 2.45 2.7 2.95 V
I
SS
Soft-Start Pin Source Current V
SS/TRK
= 0V 2 4.5 7 µA
V
TRACK
SS/TRK Accuracy, VSS - V
FB
V
SS/TRK
= 0.4V -10 3 15 mV
Oscillator
F
OSC
Oscillator Frequency 440 500 560 kHz
T
OFF_TIME
Minimum Off Time 85 ns
T
ON_TIME
Minimum On Time 100 ns
T
CL_BLANK
Current Sense Blanking Time After Rising V
SW
80 ns
Error Amplifier and Modulator
I
FB
Feedback pin bias current VFB = 0.8V 1 100 nA
I
COMP_SRC
COMP Output Source Current VFB = V
COMP
= 0.6V 80 100 µA
I
COMP_SNK
COMP Output Sink Current VFB = 1.0V, V
COMP
= 0.6V 80 100 µA
g
m
Error Amplifier Transconductance I
COMP
= ± 50 µA 450 510 600 µmho
A
VOL
Error Amplifier Voltage Gain 2000 V/V
Power Good
V
OVP
Over Voltage Protection Rising Threshold With respect to V
FB
105 108 111 %
V
OVP_HYS
Over Voltage Protection Hysteresis 2 3 %
V
PGTH
PGOOD Rising Threshold With respect to V
FB
92 94 96 %
V
PGHYS
PGOOD Falling Hysteresis 2 3 %
T
PGOOD
PGOOD deglitch time 16 µs
I
OL
PGOOD Low Sink Current V
PGOOD
= 0.4V 0.6 1 mA
I
OH
PGOOD High Leakage Current V
PGOOD
= 5V 5 100 nA
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