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