lt3430-1 Linear Technology Corporation, lt3430-1 Datasheet - Page 4

• Manufacturer Part Number: lt3430-1
• Description: High Voltage, 3a, 100khz Step-down Switching Regulator
• Manufacturer: Linear Technology Corporation

LT3430/LT3430-1
TYPICAL PERFORMANCE CHARACTERISTICS
4
2500
2000
1500
1000
500
2.4
2.0
1.6
1.2
0.8
0.4
6
5
4
3
2
0
0
–50
–50
0
Switch Peak Current Limit
Lockout and Shutdown Threshold
Error Amplifi er Transconductance
T
J
–25
–25
= 25°C
JUNCTION TEMPERATURE (°C)
JUNCTION TEMPERATURE (°C)
20
GUARANTEED MINIMUM
0
0
DUTY CYCLE (%)
40
LOCKOUT
START-UP
SHUTDOWN
TYPICAL
25
25
50
50
60
75
75
80
100
100
3430 G01
3430 G04
3430 G07
100
125
125
3000
2500
2000
1500
1000
1.234
1.229
1.219
1.214
1.209
1.204
1.224
500
40
35
30
25
20
15
10
5
0
100
0
–50
FB Pin Voltage and Current
Shutdown Supply Current
Error Amplifi er Transconductance
V
T
R
T
ERROR AMPLIFIER EQUIVALENT CIRCUIT
SHDN
A
A
V
LOAD
FB 2 • 10
= 25°C
= 25°C
–25
(
10
= 0V
=
1k
JUNCTION TEMPERATURE (°C)
50Ω
–3
INPUT VOLTAGE (V)
GAIN
)
0
20
FREQUENCY (Hz)
PHASE
10k
25
30
CURRENT
VOLTAGE
R
200k
50
OUT
100k
40
75
1M
50
C
12pF
OUT
100
V
3430 G05
3430 G02
3430 G08
C
10M
60
125
200
150
100
50
0
–50
0.5
2.0
1.5
1.0
0
250
200
150
100
300
250
200
150
100
100
600
500
400
300
200
12
50
6
0
0
0
–50
0
⎯ S ⎯ H ⎯ D ⎯ N Pin Bias Current
Shutdown Supply Current
0
Frequency Foldback
T
CURRENT REQUIRED TO FORCE SHUTDOWN
T
(FLOWS OUT OF PIN). AFTER SHUTDOWN,
A
A
–25
= 25°C
= 25°C
AT 2.38V STANDBY THRESHOLD
(CURRENT FLOWS OUT OF PIN)
0.1
CURRENT DROPS TO A FEW µA
JUNCTION TEMPERATURE (°C)
FB PIN
CURRENT
SHUTDOWN VOLTAGE (V)
V
0
IN
0.5
= 60V
0.2
25
V
FB
3430-1
(V)
50
3430
V
0.3
IN
= 15V
1.0
75
FREQUENCY
SWITCHING
0.4
100
3430 G03
3430 G06
3430 G09
34301fa
125
0.5
1.5