Datasheet

LM25037, LM25037-Q1
SNVS572D –JULY 2008–REVISED MARCH 2013 www.ti.com
Electrical Characteristics (continued)
Specifications with standard typeface are for T
J
= 25°C, and those with boldface type apply over full operating junction
temperature range of −40°C to + 125°C. V
VIN
= 12V, V
VCC
= 10V, R
RT1
= 30.1 kΩ, R
RT2
= 30.1 kΩ, V
UVLO
= 3V unless
otherwise stated.
(1)(2)
Symbol Parameter Conditions Min Typ Max Units
V
REF(UV)
Hysteresis 0.4 V
Under-Voltage Lock Out and Shutdown (UVLO Pin)
V
UVLO
Under-voltage threshold 1.20 1.25 1.295 V
I
UVLO
Hysteresis current UVLO pin sinking 17 22 26 µA
Under-voltage Shutdown Threshold UVLO voltage rising 0.35 0.45 0.6 V
Hysteresis 0.1 V
Current Sense Input (CS Pin)
V
CS
Current Limit Threshold 0.22 0.255 0.29 V
CS delay to output CS from zero to 1V. Time for OUTA and 27 ns
OUTB to fall to 90% of VCC. Output load =
0 pF.
Leading edge blanking time at CS 65 ns
CS sink impedance (clocked) Internal FET sink impedance 21 45 Ω
Current Limit Restart (RES Pin)
V
RES
RES Threshold 1.9 2 2.2 V
Charge source current V
RES
= 1.5V 14 18 21 µA
Discharge sink current V
RES
= 1V 5 8 11 µA
Soft-Start (SS Pin)
I
SS
Charging current in normal V
SS
= 0 70 100 130 µA
operation
Charging current during a hiccup V
SS
= 0 0.6 1 1.4 µA
mode restart
Soft-Stop Current Sink V
SS
= 2.0V 70 100 130 µA
Oscillator (RT1 and RT2 Pins)
DT
1
Dead-Time 1 R
RT2
= 15 kΩ 40 75 105 ns
DT
2
Dead-Time 2 R
RT2
= 50 kΩ 250 ns
F
SW1
Frequency 1 (at OUTA, half R
RT1
= 30.1 kΩ, R
RT2
= 30.1 kΩ, 178 200 222 kHz
oscillator frequency)
F
SW2
Frequency 2 (at OUTA, half R
RT1
= 11 kΩ, R
RT2
= 30.1 kΩ, 448 515 578 kHz
oscillator frequency)
DC level 2 V
Input Sync threshold 2.5 3 3.4 V
PWM Controller (Comp Pin)
Delay to output 65 ns
V
PWM-OS
SS to RAMP offset 0.7 1 1.2 V
Minimum duty cycle V
SS
= 0V 0 %
COMP Open Circuit Voltage V
FB
= 0V 4.5 4.75 5.0 V
COMP short circuit current V
FB
= 0V, COMP = 0V 0.5 1 1.5 mA
Voltage Feed-Forward (RAMP Pin)
RAMP sink impedance(Clocked) 5 20 Ω
Error Amplifier
GBW Gain Bandwidth 4 MHz
DC Gain 75 dB
Input Voltage V
FB
= COMP 1.22 1.245 1.27 V
COMP sink capability V
FB
= 1.5V COMP=1V 5 13 mA
FB Bias Current 10 nA
Main Output Drivers (OUTA and OUTB Pins)
4 Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LM25037 LM25037-Q1