LM2574, LM2574HV
SNVS104C –JUNE 1999–REVISED APRIL 2013
www.ti.com
All Output Voltage Versions Electrical Characteristics
Specifications with standard type face are for T
J
= 25°C, and those with boldface type apply over full Operating
Temperature Range. Unless otherwise specified, V
IN
= 12V for the 3.3V, 5V, and Adjustable version, V
IN
= 25V for the 12V
version, and V
IN
= 30V for the 15V version. I
LOAD
= 100 mA.
Symbol Parameter Conditions LM2574-XX Units
LM2574HV-XX (Limits)
Typ Limit
(1)
DEVICE PARAMETERS
I
b
Feedback Bias Adjustable Version Only, V
OUT
= 5V 50 100/500 nA
Current
f
O
Oscillator Frequency See
(2)
52 kHz
47/42 kHz(Min)
58/63 kHz(Max)
V
SAT
Saturation Voltage I
OUT
= 0.5A
(3)
0.9 V
1.2/1.4 V(max)
DC Max Duty Cycle (ON) See
(4)
98 %
93 %(Min)
I
CL
Current Limit Peak Current
(3)(2)
1.0 A
0.7/0.65 A(Min)
1.6/1.8 A(Max)
I
L
Current Output = 0V 2 mA(Max)
Output Leakage Output = −1V 7.5 mA
Output = −1V
(5) (6)
30 mA(Max)
I
Q
Quiescent Current See
(5)
5 mA
10 mA(Max)
I
STBY
Standby Quiescent ON /OFF Pin= 5V (OFF) 50 μA
Current 200 μA(Max)
θ
JA
Thermal Resistance P Package, Junction to Ambient
(7)
92
θ
JA
P Package, Junction to Ambient
(8)
72
°C/W
θ
JA
NPA Package, Junction to Ambient
(7)
10
θ
JA
NPA Package, Junction to Ambient
(8)
2 78
ON /OFF CONTROL Test Circuit Figure 24
V
IH
ON /OFF Pin Logic V
OUT
= 0V 1.4 2.2/2.4 V(Min)
Input Level
V
IL
V
OUT
= Nominal Output Voltage 1.2 1.0/0.8 V(Max)
I
H
ON /OFF Pin Input ON /OFF Pin = 5V (OFF) 12 μA
Current 30 μA(Max)
I
IL
ON /OFF Pin = 0V (ON) 0 μA
10 μA(Max)
(1) All limits specified at room temperature (Standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. All limits are used to calculate Average Outgoing Quality Level.
(2) The oscillator frequency reduces to approximately 18 kHz in the event of an output short or an overload which causes the regulated
output voltage to drop approximately 40% from the nominal output voltage. This self protection feature lowers the average power
dissipation of the IC by lowering the minimum duty cycle from 5% down to approximately 2%.Figure 9
(3) Output pin sourcing current. No diode, inductor or capacitor connected to output pin.
(4) Feedback pin removed from output and connected to 0V.
(5) Feedback pin removed from output and connected to +12V for the Adjustable, 3.3V, and 5V versions, and +25V for the 12V and 15V
versions, to force the output transistor OFF.
(6) V
IN
= 40V (60V for high voltage version).
(7) Junction to ambient thermal resistance with approximately 1 square inch of printed circuit board copper surrounding the leads. Additional
copper area will lower thermal resistance further. See Application Hints in this data sheet and the thermal model in Switchers Made
Simple software.
(8) Junction to ambient thermal resistance with approximately 4 square inches of 1 oz. (0.0014 in. thick) printed circuit board copper
surrounding the leads. Additional copper area will lower thermal resistance further (See Note 7)
6 Submit Documentation Feedback Copyright © 1999–2013, Texas Instruments Incorporated
Product Folder Links: LM2574 LM2574HV
