Datasheet

5
LT1375/LT1376
13756fd
TYPICAL PERFORMANCE CHARACTERISTICS
UW
TEMPERATURE (°C)
–50
500
400
300
200
8
4
0
25 75
1375/76 G04
–25 0
50 100 125
CURRENT (µA)
CURRENT REQUIRED TO FORCE SHUTDOWN
(FLOWS OUT OF PIN). AFTER SHUTDOWN,
CURRENT DROPS TO A FEW µA
AT 2.38V STANDBY THRESHOLD
(CURRENT FLOWS OUT OF PIN)
Shutdown Pin Bias Current
JUNCTION TEMPERATURE (°C)
–50
TRANSCONDUCTANCE (µMho)
2500
2000
1500
1000
500
0
0
50
75
1375/76 G02
–25
25
100
125
Error Amplifier Transconductance
FREQUENCY (Hz)
GAIN (
µ
Mho)
PHASE (DEG)
3000
2500
2000
1500
1000
500
200
150
100
50
0
–50
100 10k 100k 10M
1375/76 G03
1k 1M
GAIN
PHASE
ERROR AMPLIFIER EQUIVALENT CIRCUIT
R
OUT
200k
C
OUT
12pF
V
C
R
LOAD
= 50Ω
V
FB
2 • 10
–3
)(
Error Amplifier Transconductance
Frequency Foldback
LOAD CURRENT (mA)
0
INPUT VOLTAGE (V)
8.5
8.0
7.5
7.0
6.5
6.0
5.5
5.0
10 100 1000
1375/76 G12
MINIMUM INPUT VOLTAGE CAN BE
REDUCED BY ADDING A SMALL EXTERNAL
PNP. SEE APPLICATIONS INFORMATION
MINIMUM
VOLTAGE TO
START WITH
STANDARD
CIRCUIT
MINIMUM VOLTAGE
TO RUN WITH
STANDARD CIRCUIT
LT1376 Minimum Input Voltage
with 5V Output
Shutdown Supply Current
INPUT VOLTAGE (V)
0
INPUT SUPPLY CURRENT (µA)
30
25
20
15
10
5
0
5101520
1375/76 G06
25
V
SHUTDOWN
= 0V
JUNCTION TEMPERATURE (°C)
–50
2.40
2.36
2.32
0.8
0.4
0
25 75
1375/76 G05
–25 0
50 100 125
SHUTDOWN PIN VOLTAGE (V)
STANDBY
START-UP
SHUTDOWN
Standby and Shutdown Thresholds
Shutdown Supply Current
SHUTDOWN VOLTAGE (V)
0
INPUT SUPPLY CURRENT (µA)
150
125
100
75
50
25
0
0.1 0.2 0.3 0.4
1375/76 G07
0.5
V
IN
= 25V
V
IN
= 10V
FEEDBACK PIN VOLTAGE (V)
0
SWITCHING FREQUENCY (kHz) OR CURRENT (µA)
500
400
300
200
100
0
2.0
1375/76 G10
0.5
1.0
1.5
2.5
SWITCHING
FREQUENCY
FEEDBACK PIN
CURRENT
Switching Frequency
JUNCTION TEMPERATURE (°C)
–50
600
550
500
450
400
100
1375/76 G11
–25 0 25 50 75 125
FREQUENCY (kHz)