Datasheet
3
LT1611
TYPICAL PERFOR A CE CHARACTERISTICS
UW
LOAD CURRENT (mA)
EFFICIENCY (%)
85
80
75
70
65
60
55
50
1611 G01
0
25
50 75 100 125 150
V
IN
= 3V
V
IN
= 5V
TEMPERATURE (°C)
–50 0 50–25 25 75 100
NFB PIN BIAS CURRENT (µA)
1611 G03
6
5
4
3
2
1
0
SWITCH CURRENT (mA)
0 100 200 300 400 500 600 700
V
CESAT
(mV)
1611 G04
700
600
500
400
300
200
100
0
T
A
= 25°C
SHDN PIN VOLTAGE (V)
012345
SHDN PIN BIAS CURRENT (µA)
1611 G05
50
40
30
20
10
0
DUTY CYCLE (%)
10
SWITCH CURRENT LIMIT (mA)
900
800
700
600
500
400
300
200
100
0
1611 G06
20 30 40 50 60 70 80
T
A
= 25°C
TEMPERATURE (°C)
–50 –25 0 25 50 75 100
SWITCHING FREQUENCY (MHz)
1611 G07
2.00
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0
V
IN
= 5V
V
IN
= 1.5V
TEMPERATURE (°C)
–50
SWITCH CURRENT LIMIT (mA)
900
800
700
600
500
400
300
200
100
0
1611 G09
–25 0 25 50 75 100
Efficiency, V
OUT
= –5V
NFB Pin Bias Current vs
TemperatureV
NFB
vs Temperature
Switch V
CESAT
vs Switch Current Switch Current Limit vs Duty CycleSHDN Pin Bias Current vs V
SHDN
Oscillator Frequency vs
Temperature
Switch Current Limit vs
Temperature (Duty Cycle = 30%)
No-Load Operating Quiescent
Current vs Temperature*
TEMPERATURE (°C)
–50 0 50–25 25 75 100
V
NFB
(V)
1611 G02
–1.245
–1.240
–1.235
–1.230
–1.225
–1.220
–1.215
–1.210
TEMPERATURE (°C)
–50 0 50–25 25 75 100
OPERATING CURRENT (mA)
1611 G08
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
* Includes bias current through R1, R2 and Schottky leakage current at T ≥ 75°C