LT1242 LINER [Linear Technology], LT1242 Datasheet - Page 11

• Manufacturer Part Number: LT1242
• Description: High Speed Current Mode Pulse Width Modulators
• Manufacturer: LINER [Linear Technology]

TYPICAL
EXTERNAL
D1 IS REQUIRED IF THE SYNC AMPLITUDE IS LARGE
ENOUGH TO PULL THE BOTTOM OF C
300mV BELOW GROUND.
INPUT
SYNC
External Clock Synchronization
C
+
0.01 F
R1
R2
A
100k
PPLICATI
R
47
V
T
R
C
REF
T
T
8
4
R
COMP
/C
V
FB
T
REF
T
8
4
1
2
/C
T
T
D1
V
OSCILLATOR
MORE THAN
CLAMP
5V REF
LT1241 • TA01
2.5V
–
+
(
O
R2
R1
1.67
+ 1
U
(
S
I
PK (MAX)
Adjustable Clamp Level with Soft Start
C
1mA
R
5.6V
OSCILLATOR
V
CLAMP
2R
I
COMP
R
SENSE
V
FB
S
REF
8
1
2
3
MAIN BIAS
R
5V REF
WHERE: 0V V
1V
2.5V
–
+
+
–
CLAMP
REFERENCE PULL-DOWN
REFERENCE ENABLE
T
1.0V
1mA
BLANKING
Soft Start
S
R
t
5.6V
SOFT START
1.5V
2R
PULL-DOWN
5V REF
+
–
OUTPUT
R
= –ln 1 –
LOCKOUT
UV
1V
–
+
18V
3 • V
LT1241 Series
V
CLAMP
C
OUTPUT
I
SENSE
V
GND
CC
7
6
5
3
1.5V
C
R1 R2
R1 + R2
–
+
LT1241 • TA03
V
IN
LT1241 • TA02
R
11
S