LT1170 Linear Technology, LT1170 Datasheet - Page 3

• Manufacturer Part Number: LT1170
• Description: 100kHz/ 5A/ 2.5A and 1.25A High Efficiency Switching Regulators
• Manufacturer: Linear Technology

perature range, otherwise specifications are at T
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
V
I
g
A
I
V
BV
V
I
B
Q
LIM
m
REF
V
FB
SAT
Reference Voltage
Feedback Input Current
Error Amplifier
Transconductance
Error Amplifier Source or
Sink Current
Error Amplifier Clamp
Voltage
Reference Voltage Line
Regulation
Error Amplifier Voltage Gain
Minimum Input Voltage (Note 5)
Supply Current
Control Pin Threshold
Normal/Flyback Threshold
on Feedback Pin
Flyback Reference Voltage
(Note 5)
Change in Flyback Reference
Voltage
Flyback Reference Voltage
Line Regulation (Note 5)
Flyback Amplifier
Transconductance (g
Flyback Amplifier Source
and Sink Current
Output Switch Breakdown
Voltage
Output Switch
“On” Resistance (Note 3)
Control Voltage to Switch
Current Transconductance
Switch Current Limit
m
)
(LT1170)
(LT1171)
(LT1172)
CONDITIONS
Measured at Feedback Pin
V
V
V
Hi Clamp, V
Lo Clamp, V
3V V
V
0.9V V
3V V
Duty Cycle = 0
I
0.05 I
I
7V V
V
I
3V V
I
LT1170
LT1171
LT1172
LT1170
LT1171
LT1172
Duty Cycle = 50%
Duty Cycle = 50%
Duty Cycle = 80% (Note 4)
Duty Cycle = 50%
Duty Cycle = 50%
Duty Cycle = 80% (Note 4)
Duty Cycle = 50%
Duty Cycle = 50%
Duty Cycle = 80% (Note 4)
FB
FB
FB
SW
C
FB
I
C
C
I
C
C
C
= 0.8V
= 1.5V
= 0.8V
= 0.6V
= 50 A
= 50 A
= 50 A
= V
= 25 A
= 10 A
= 1.5mA
A
IN
IN
IN
IN
REF
FB
= 25 C. V
C
V
V
V
V
FB
FB
1.4V
1mA
MAX
MAX
MAX
MAX
= 1V
= 1.5V
, V
,
The
IN
C
= 0.6V
Source
Sink
LT1170/LT1171/LT1172
LT1170HV/LT1171HV/LT1172HV
LT1172S8
= 15V, V
denotes the specifications which apply over the full operating tem-
C
= 0.5V, V
FB
= V
T
T
T
T
T
T
J
J
J
J
J
J
REF
25 C
25 C
25 C
25 C
25 C
25 C
, output pin open, unless otherwise noted.
LT1 170/LT1 171/LT1172
1.224
1.214
3000
2400
MIN
1.80
0.25
15.0
14.0
1.25
1.25
1.00
150
120
500
150
0.8
0.6
0.4
4.5
2.5
2.5
2.0
15
25
65
75
60
5
5
4
1.244
1.244
4400
0.38
0.45
16.3
0.01
0.15
0.30
0.60
TYP
350
200
800
300
2.6
0.9
6.8
32
40
90
90
80
6
8
4
2
1.264
1.274
1100
6000
7000
MAX
2.30
0.52
0.03
1.08
1.25
0.54
17.6
18.0
0.03
0.24
0.50
1.00
750
350
400
650
3.0
5.0
5.5
5.0
3.0
3.5
2.5
70
70
10
11
10
9
9
UNITS
3
mho
mho
%/V
%/V
mho
V/V
A/V
A/V
A/V
mA
nA
nA
V
V
A
A
V
V
V
V
V
V
V
V
V
A
A
V
V
V
A
A
A
A
A
A
A
A
A