Electrical Characteristics — LM1577-12, LM2577-12
(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.
LM1577-12
Symbol
Parameter
Conditions
Typical
Limit
(Notes 3, 4)
DEVICE PARAMETERS
Error Amplifier
Output Swing
Upper Limit
V
FEEDBACK
= 10.0V
Lower Limit
Error Amplifier
Output Current
I
SS
Soft Start Current
V
FEEDBACK
= 15.0V
V
FEEDBACK
= 10.0V to 15.0V
V
COMP
= 1.0V
V
FEEDBACK
= 10.0V
V
COMP
= 0V
V
COMP
= 1.5V
I
SWITCH
= 100 mA
2.4
2.2/2.0
0.3
0.40/0.55
0.40/0.55
2.2/2.0
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
V
SAT
Switch Leakage
Current
Switch Saturation
Voltage
NPN Switch
Current Limit
V
SWITCH
= 65V
V
FEEDBACK
= 15V (Switch Off)
I
SWITCH
= 2.0A
V
COMP
= 2.0V (Max Duty Cycle)
4.5
3.7/3.0
5.3/6.0
3.7/3.0
5.3/6.0
95
93/90
12.5
93/90
2.5/1.5
7.5/9.5
µA(min)
µA(max)
%
%(min)
A/V
LM2577-12
Limit
(Note 5)
Units
(Limits)
±
200
±
130/
±
90
±
300/
±
400
5.0
±
130/
±
90
±
300/
±
400
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)
Electrical Characteristics — LM1577-15, LM2577-15
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)
SYSTEM PARAMETERS
Circuit of
Figure 2
(Note 6)
V
OUT
Output Voltage
V
IN
= 5V to 12V
I
LOAD
= 100 mA to 600 mA
Line Regulation
(Note 3)
V
IN
= 3.5V to 12V
I
LOAD
= 300 mA
Load Regulation
η
I
S
V
IN
= 5V
I
LOAD
= 100 mA to 600 mA
Efficiency
Input Supply Current
V
IN
= 5V, I
LOAD
= 600 mA
V
FEEDBACK
= 18.0V
(Switch Off)
I
SWITCH
= 2.0A
V
COMP
V
UV
Input Supply
= 2.0V
2.90
3
LM2577-15
Limit
(Note 5)
Units
(Limits)
15.0
14.50/14.25
15.50/15.75
20
50/100
20
50/100
80
7.5
10.0/14.0
25
50/85
50/85
10.0/14.0
50/100
50/100
14.50/14.25
15.50/15.75
V
V(min)
V(max)
mV
mV(max)
mV
mV(max)
%
mA
mA(max)
mA
mA(max)
V
www.national.com
DEVICE PARAMETERS
(Max Duty Cycle)
I
SWITCH
= 100 mA
NSC [ NATIONAL SEMICONDUCTOR ]
