Datasheet

LT1308A/LT1308B
5
1308abfb
TYPICAL PERFORMANCE CHARACTERISTICS
SHDN Pin Bias Current vs Voltage
FB, LBI Bias Current vs
Temperature
Low Battery Detector Reference
vs Temperature
Oscillator Frequency vs
Temperature
LT1308A Quiescent Current vs
Temperature
Feedback Pin Voltage vs
Temperature
LT1308B
12V Output Effi ciency
Switch Current Limit vs
Duty Cycle
Switch Saturation Voltage
vs Current
LOAD CURRENT (mA)
90
85
80
75
70
65
60
55
50
1 100 1000
1308A/B G04
10
EFFICIENCY (%)
V
IN
= 5V
V
IN
= 3.3V
DUTY CYCLE (%)
0
CURRENT LIMIT (A)
3.0
3.5
80
1308 • G05
2.5
2.0
20
40
60
100
4.0
SWITCH CURRENT (A)
0
SWITCH V
CESAT
(mV)
2.0
85°C
1308 G06
0.5
1.0
1.5
500
400
300
200
100
0
25°C
–40°C
SHDN PIN VOLTAGE (V)
0
SHDN PIN CURRENT (µA)
50
40
30
20
10
0
8
1308 G07
2
4
6
10
–40°C
25°C
85°C
TEMPERATURE (°C)
–50 –25
BIAS CURRENT (nA)
05025
75
100
1308 • G08
80
70
60
50
40
30
20
10
0
LBI
FB
TEMPERATURE (°C)
–50 –25
V
REF
(mV)
05025
75
100
1308 • G09
203
202
201
200
199
198
197
196
195
TEMPERATURE (°C)
–50 –2.5
FREQUENCY (kHz)
05025
75
100
1308 • G10
800
750
700
650
600
550
500
450
400
TEMPERATURE (°C)
–50 –25
QUIESCENT CURRENT (µA)
05025
75
100
1308 • G11
180
170
160
150
140
130
120
110
100
TEMPERATURE (°C)
–50 –25
V
FB
(V)
05025
75
100
1308 • G12
1.25
1.24
1.23
1.22
1.21
1.20
1.19
1.18