Datasheet

LT1170/LT1171/LT1172
8
117012fg
TYPICAL PERFORMANCE CHARACTERISTICS
BLOCK DIAGRAM
FREQUENCY (Hz)
1k
TRANSCONDUCTANCE (µmho)
7000
6000
5000
4000
3000
2000
1000
0
–1000
10k 100k
1170/1/2 G19
1M 10M
–30
0
30
60
90
120
150
180
210
PHASE (DEG)
Q
g
m
TEMPERATURE (°C)
–50
FEEDBACK PIN VOLTAGE (mV)
500
490
480
470
460
450
440
430
420
410
400
0
50
75
1170/1/2 G20
–25 25
100
125
150
–24
–22
–20
–18
–16
–14
–12
–10
–8
–6
–4
FEEDBACK PIN CURRENT (µA)
FEEDBACK PIN CURRENT
(AT THRESHOLD)
FEEDBACK PIN VOLTAGE
(AT THRESHOLD)
Transconductance of Error
Amplifier
Normal/Flyback Mode Threshold on
Feedback Pin
1.24V
REF
1170/1/2 BD
ERROR
AMP
100kHz
OSC
2.3V
REG
V
IN
FB
+
–
+
–
SHUTDOWN
CIRCUIT
V
C
COMP
LOGIC DRIVER
ANTI-
SAT
FLYBACK
ERROR
AMP
16V
SWITCH
OUT
5A, 75V
SWITCH
0.02Ω
(0.04Ω
(0.16Ω
LT1171)
LT1172)
0.16Ω
CURRENT
AMP
GAIN 6
≈
0.15V
ALWAYS CONNECT E1 TO THE GROUND PIN ON MINIDIP, 8- AND 16-PIN SURFACE MOUNT PACKAGES.
E1 AND E2 INTERNALLY TIED TO GROUND ON TO-3 AND TO-220 PACKAGES.
†
MODE
SELECT
E1
†
E2
(LT1170 AND LT1171 ONLY)
LT1172