LT1071 Linear Technology, LT1071 Datasheet - Page 5

• Manufacturer Part Number: LT1071
• Description: 5A and 2.5A High Efficiency Switching Regulators
• Manufacturer: Linear Technology

TYPICAL PERFORMANCE CHARACTERISTICS
500
490
480
470
460
450
440
430
420
400
410
160
140
120
100
400
350
300
250
200
150
100
80
60
40
20
50
0
*
0
–50
– 75
AVERAGE LT1070 POWER SUPPLY CURRENT IS
FOUND BY MULTIPLYING DRIVER CURRENT BY
DUTY CYCLE, THEN ADDING QUIESCENT CURRENT
Driver Current* vs Switch Current
0
Normal/Flyback Mode Threshold
on Feedback Pin
Shutdown Thresholds
V
REGULATOR CURRENT DROPS
BELOW 300 A
C
–25
– 50
VOLTAGE IS REDUCED UNTIL
FEEDBACK PIN VOLTAGE
(OUT OF V
– 25
1
(AT THRESHOLD)
CURRENT
0
SWITCH CURRENT (A)
TEMPERATURE ( C)
TEMPERATURE ( C)
T
0
J
25
C
= – 55 C
2
FEEDBACK PIN CURRENT
PIN)
VOLTAGE
25
50
(AT THRESHOLD)
50
3
75
75
T
J
100 125 150
100
W
25 C
4
1070/71 G16
1070/71 G13
1070/71 G10
125
U
150
5
–24
–22
–20
–18
–16
–14
–12
–10
– 8
– 4
– 6
– 400
–350
–300
–250
–200
–150
–100
– 50
0
16
15
14
13
12
11
10
9
8
7
6
*
200
180
160
140
120
100
UNDER VERY LOW OUTPUT CURRENT
CONDITIONS, DUTY CYCLE FOR MOST
CIRCUITS WILL APPROACH 10% OR LESS
Supply Current vs Input Voltage*
0
80
60
40
20
0
11
10
T
9
8
7
6
5
4
3
2
1
J
Shutdown Mode Supply Current
0
–75
= 25 C
Idle Supply Current
vs Temperature
V
10
10
C
– 50
= 0.6V
90% DUTY CYCLE
50% DUTY CYCLE
10% DUTY CYCLE
0% DUTY CYCLE
20
T
INPUT VOLTAGE (V)
J
–25
20
= 150 C
V
30
C
TEMPERATURE ( C)
PIN VOLTAGE (mV)
0
I
V
40
SWITCH
V
30
SUPPLY
SUPPLY
– 55 C T
25
50
50
40
= 60V
60
= 3V
10mA
J
75
70
125 C
50
1070/71 G11
100
80
1070/71 G14
1070/71 G14
90
125
60
100
150
5000
4500
4000
3500
3000
2500
2000
1500
1000
160
140
120
100
500
500
450
400
350
300
250
200
150
100
80
40
60
20
50
0
0
0
–75
0
0
Supply Current vs Supply Voltage
(Shutdown Mode)
Error Amplifier Transconductance
Feedback Pin Clamp Voltage
T
J
0.1
– 50
= 25 C
10
LT1070/LT1071
0.2
–25
FEEDBACK CURRENT (mA)
SUPPLY VOLTAGE (V)
0.3
TEMPERATURE ( C)
20
0
– 55 C
150 C
25 C
0.4
V
C
V
25
C
= 50mV
0.5
30
= 0V
50
0.6
g
m
40
75
=
0.7
V
I
100
0.8
(V
(FB PIN)
50
1070/71 G12
C
1070/71 G14
1070/71 G18
125
0.9
PIN)
5
150
1.0
60