Datasheet

4
LT1507
Shutdown Pin Bias Current
JUNCTION TEMPERATURE (°C) 
–50

2.40
2.36
2.32
0.8
0.4
0
25 75
LT1507 • TPC05
–25 0
50 100 125
SHUTDOWN PIN VOLTAGE (V)
STANDBY
STARTUP
SHUTDOWN
Standby and Shutdown Thresholds
TYPICAL PERFORMANCE CHARACTERISTICS
U
W
INPUT VOLTAGE (V)
0
0
INPUT SUPPLY CURRENT (µA)
5
10
15
20
25
30
36912
LT1507 • TPC06
15
V
SHDN
= 0V
Shutdown Supply Current
Shutdown Supply Current Error Amplifier Transconductance
TEMPERATURE (°C) 
–50

500
400
300
200
8
4
0
25 75
L11507 • TPC04
–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)
JUNCTION TEMPERATURE (°C)
–50
TRANSCONDUCTANCE (µmho)
2500
2000
1500
1000
500
0
0
50
75
LT1507 • TPC08
–25
25
100
125
SHUTDOWN VOLTAGE (V)
0
INPUT SUPPLY CURRENT (µA)
150
125
100
75
50
25
0
0.1 0.2 0.3 0.4
LT1507 • TPC07
0.5
V
IN
= 10V
FREQUENCY (Hz)
GAIN (µmho)
PHASE (DEG)
3000
2500
2000
1500
1000
500
200
150
100
50
0
–50
100 10k 100k 10M
LT1507 • TPC09
1k 1M
GAIN
PHASE
R
OUT

200k
C
OUT

12pF
V
C
V
FB
× 2e
–3
ERROR AMPLIFIER EQUIVALENT CIRCUIT
R
LOAD
= 50Ω
Error Amplifier Transconductance
Minimum Input Voltage
with 3.3V OutputSwitching Frequency
FEEDBACK PIN VOLTAGE (V)
0
SWITCHING FREQUENCY (kHz) OR CURRENT (µA)
500
400
300
200
100
0
2.0
LT1507 • TPC10
0.5
1.0
1.5
2.5
SWITCHING
FREQUENCY
FEEDBACK PIN
CURRENT
Frequency Foldback
JUNCTION TEMPERATURE (°C)
–50

600
550
500
450
400
100
LT1507 • TPC11
–25 0 25 50 75 125
FREQUENCY (kHz)
LOAD CURRENT (mA)
1
5.0
INPUT VOLTAGE (V)
5.5
6.0
6.5
10 100 1000
LT1507 • TPC12
4.5
4.0
3.5
3.0
MINIMUM VOLTAGE
TO START WITH 
STANDARD CIRCUIT
MINIMUM VOLTAGE
TO RUN WITH 
STANDARD CIRCUIT
MINIMUM INPUT VOLTAGE CAN BE REDUCED 
BY ADDING A SMALL EXTERNAL PNP. SEE 
APPLICATIONS INFORMATION
