Electrical Characteristics — LM1577-ADJ, LM2577-ADJ
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, V
FEEDBACK
= V
REF
, and I
SWITCH
= 0.
LM1577-ADJ LM2577-ADJ
Symbol
Parameter
Conditions
Typical
Limit
(Notes 3, 4)
SYSTEM PARAMETERS
Circuit of
Figure 3
(Note 6)
V
OUT
Output Voltage
V
IN
= 5V to 10V
I
LOAD
= 100 mA to 800 mA
∆V
OUT
/
∆V
IN
∆V
OUT
/
∆I
LOAD
η
I
S
Efficiency
Input Supply Current
DEVICE PARAMETERS
V
FEEDBACK
= 1.5V (Switch Off)
I
SWITCH
= 2.0A
V
COMP
= 2.0V (Max Duty Cycle)
I
SWITCH
= 100 mA
7.5
10.0/14.0
25
50/85
2.90
2.70/2.65
3.10/3.15
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
V
COMP
= 1.0V
I
COMP
= −30 µA to +30 µA
V
COMP
= 1.0V
V
COMP
R
COMP
= 1.1V to 1.9V
= 1.0 MΩ (Note 7)
52
48/42
56/62
V
REF
Reference
Voltage
∆V
REF
/
∆V
IN
I
B
G
M
Reference Voltage
Line Regulation
Error Amp
Input Bias Current
Error Amp
Transconductance
A
VOL
Error Amp
Voltage Gain
Error Amplifier
Output Swing
3700
2400/1600
4800/5800
800
500/250
2.4
2.2/2.0
0.3
0.40/0.55
0.40/0.55
2.2/2.0
500/250
2400/1600
4800/5800
100
300/800
300/800
nA
nA(max)
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
∆I
SWITCH
/
∆V
COMP
Maximum Duty Cycle
Switch
Transconductance
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
1.230
0.5
1.214/1.206
1.246/1.254
48/42
56/62
1.214/1.206
1.246/1.254
2.70/2.65
3.10/3.15
50/85
10.0/14.0
mA
mA(max)
mA
mA(max)
V
V(min)
V(max)
kHz
kHz(min)
kHz(max)
V
V(min)
V(max)
mV
Load Regulation
Line Regulation
(Note 3)
V
IN
= 3.5V to 10V
I
LOAD
= 300 mA
V
IN
= 5V
I
LOAD
= 100 mA to 800 mA
V
IN
= 5V, I
LOAD
= 800 mA
20
50/100
20
50/100
80
50/100
50/100
12.0
11.60/11.40
12.40/12.60
11.60/11.40
12.40/12.60
Limit
(Note 5)
V
V(min)
V(max)
mV
mV(max)
mV
mV(max)
%
Units
(Limits)
V
UV
Input Supply
Undervoltage Lockout
Upper Limit
V
FEEDBACK
= 1.0V
Lower Limit
V
FEEDBACK
= 1.5V
V
FEEDBACK
= 1.0V to 1.5V
V
COMP
= 1.0V
V
FEEDBACK
= 1.0V
V
COMP
= 0V
Error Amp
Output Current
I
SS
Soft Start Current
±
200
±
130/
±
90
±
300/
±
400
5.0
±
130/
±
90
±
300/
±
400
5
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