ltc4253a-adj Linear Technology Corporation, ltc4253a-adj Datasheet - Page 32

• Manufacturer Part Number: ltc4253a-adj
• Description: 48v Hot Swap Controller With Sequencer
• Manufacturer: Linear Technology Corporation

RELATED PARTS
APPLICATIO S I FOR ATIO
PART NUMBER
LT1640AH/LT1640AL
LT1641-1/LT1641-2
LTC1642
LT4250
LTC4251/LTC4251-1
LTC4251-2
LTC4252-1/LTC4252-2
LTC4252A-1/LTC4252A-2
LTC4260
LTC4253A-ADJ
Circuit Breaker with Foldback Current Limit
Figure 17 shows the LTC4253A-ADJ in a foldback current
limit application. When V
supply, current flows through resistors R4 and R5. This
results in a voltage drop across R5 and a corresponding
reduction in voltage drop across the sense resistor, R
the ACL amplifier servos the sense voltage between the
32
RESET
(LONG PIN)
– 48V RTN
(LONG PIN)
– 48V RTN
(SHORT PIN)
– 48V
(LONG PIN)
Figure 17. –48V/2.5A Application with Foldback Current Limiting and Transistor Enabled Sequencing Without Feedback
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone]
2.05k
20k
1%
1%
R2
R1
2k
1%
255k
1%
R11
47k
U
R3
●
DESCRIPTION
Negative High Voltage Hot Swap Controllers in SO-8
Positive High Voltage Hot Swap Controllers in SO-8
Fault Protected Hot Swap Controller
– 48V Hot Swap Controller
– 48V Hot Swap Controllers in SOT-23
– 48V Hot Swap Controllers in MS8/MS10
Positive Voltage Hot Swap Controller with I
Compatible Monitoring
C1 10nF
FAX: [phone]
0.1µF
C
C
OUT
20k(1/4W)/2
SS
SQ
U
33nF
is shorted to the – 48V RTN
10k
C
1µF
R
T
UVL
UV
OVL
OV
RESET
SS
SQTIMER
TIMER
IN
V
LTC4253A-ADJ
IN
V
EE
EN2 EN3
W
PWRGD1
PWRGD2
PWRGD3
SEL
●
DRAIN
SENSE
www.linear.com
GATE
V
IN
U
C
1µF
IN
3.3M
R
D
S
R6
100k
, as
2
C
†
R4
38.3k
10nF
22Ω
R5
C
R7
100k
C
SENSE and V
current through R
during an output short-circuit condition. Without foldback
current limiting resistor R5, the current is limited to 3A
during analog current limit. With R5, the short-circuit
current is limited to 0.5A when V
†
R
10Ω
C
R8
100k
†
+
COMMENTS
Negative High Voltage Supplies from -10V to -80V
Supplies from 9V to 80V, Autoretry/Latched Off
3V to 16.5V, Overvoltage Protection up to 33V
Active Current Limiting, Supplies from – 20V to – 80V
Fast Active Current Limiting, Supplies from – 15V
Fast Active Current Limiting, Supplies from – 15V,
Drain Accelerated Response, 1% Accurate UV/OV Thresholds
Onboard ADC for Current and Voltage Monitoring,
8.5V to 80V Operation
Q1
IRF530S
R
0.02Ω
S
0.1µF
C2
100µF
C3
EE
pins to about 60mV. The short-circuit
S
R9
100k
R10
3k
reduces as the V
MODULE 1
EN
POWER
© LINEAR TECHNOLOGY CORPORATION 2005
†
MODULE 2
EN
FMMT493
POWER
V
OUT
OUT
LT/TP 0805 500 • PRINTED IN USA
OUT
is shorted to 71V.
voltage increases
EN
MODULE 3
POWER
EN
MODULE 4
4253 F17
4253a-adjf
POWER