Electrical Characteristics — LM1577-15, LM2577-15
(Continued)
Specifications with standard type face are for T
J
= 25˚C, and those in
bold type face
apply over full
Operating Temperature
Range.
Unless otherwise specified, V
IN
= 5V, and I
SWITCH
= 0.
LM1577-15
Symbol
Parameter
Conditions
Typical
Limit
(Notes 3, 4)
DEVICE PARAMETERS
Undervoltage
Lockout
f
O
Oscillator Frequency
Measured at Switch Pin
I
SWITCH
= 100 mA
Measured at Feedback Pin
V
IN
= 3.5V to 40V
V
COMP
= 1.0V
V
IN
= 3.5V to 40V
52
48/42
56/62
V
REF
Output Reference
Voltage
Output Reference
Voltage Line Regulation
R
FB
G
M
Feedback Pin Input
Voltage Line Regulator
Error Amp
Transconductance
A
VOL
Error Amp
Voltage Gain
Error Amplifier
Output Swing
I
COMP
= −30 µA to +30 µA
V
COMP
= 1.0V
V
COMP
R
COMP
= 1.1V to 1.9V
= 1.0 MΩ
300
170/110
420/500
65
40/20
2.4
2.2/2.0
0.3
= 18.0V
= 12.0V to 18.0V
0.4/0.55
0.40/0.55
2.2/2.0
40/20
170/110
420/500
µmho
µmho(min)
µmho(max)
V/V
V/V(min)
V
V(min)
V
V(max)
µA
µA(min)
µA(max)
µA
2.5/1.5
7.5/9.5
D
Maximum Duty
Cycle
Switch
Transconductance
I
L
Switch Leakage
Current
V
SAT
Switch Saturation
Voltage
NPN Switch
Current Limit
V
SWITCH
= 65V
V
FEEDBACK
= 18.0V
(Switch Off)
I
SWITCH
= 2.0A
V
COMP
= 2.0V
4.3
3.7/3.0
5.3/6.0
3.7/3.0
5.3/6.0
(Max Duty Cycle)
V
COMP
= 2.0V
V
COMP
= 1.5V
I
SWITCH
= 100 mA
95
93/90
12.5
93/90
2.5/1.5
7.5/9.5
µA(min)
µA(max)
%
%(min)
A/V
12.2
kΩ
15
10
14.70/14.55
15.30/15.45
48/42
56/62
14.70/14.55
15.30/15.45
2.70/2.65
3.10/3.15
2.70/2.65
3.10/3.15
V(min)
V(max)
kHz
kHz(min)
kHz(max)
V
V(min)
V(max)
mV
LM2577-15
Limit
(Note 5)
Units
(Limits)
(Note 7)
Upper Limit
V
FEEDBACK
= 12.0V
Lower Limit
V
FEEDBACK
Error Amp
Output Current
I
SS
Soft Start Current
V
FEEDBACK
V
COMP
= 1.0V
±
200
±
130/
±
90
±
300/
±
400
5.0
±
130/
±
90
±
300/
±
400
V
FEEDBACK
= 12.0V
V
COMP
= 0V
10
300/600
0.5
0.7/0.9
0.7/0.9
300/600
µA
µA(max)
V
V(max)
A
A(min)
A(max)
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