LT4356MP-1 Linear Technology Corporation, LT4356MP-1 Datasheet - Page 15

• Manufacturer Part Number: LT4356MP-1
• Description: Surge Stopper
• Manufacturer: Linear Technology Corporation

Set the current through R1 and R2 during the overvoltage
condition to 250μA.
Choose 4.99k for R2.
The closest standard value for R1 is 59k.
Next calculate the sense resistor, R
C
The closest standard value for C
TYPICAL APPLICATIONS
APPLICATIONS INFORMATION
TMR
R2 =
R1 =
R
C
SNS
TMR
is then chosen for 1ms of early warning time:
(
250µA
=
1.25V
=
16V – 1.25V
50mV
1ms • 5µA
I
LIM
100mV
1.25V
= 5k
=
50mV
)
5A
= 50nF
• R2
= 10mΩ
Wide Input Range 5V to 28V Hot Swap with Undervoltage Lockout
= 58.88k
V
IN
TMR
SNS
is 47nF .
47nF
R6
118k
R7
49.9k
, value:
C1
14
16
9
A
IN
SHDN
V
OUT
CC
+
8
20mΩ
R
SNS
GND
SNS
LT4356S-1
12
SUD50N03-10
7
Finally, calculate R4 and R5 for the 6V low battery threshold
detection:
Choose 100k for R5.
Select 383k for R4.
The pass transistor, Q1, should be chosen to withstand
the output short condition with V
The total overcurrent fault time is:
The power dissipation on Q1 equals to:
These conditions are well within the Safe Operating Area
of IRLR2908.
GATE
TMR
Q1
R4 =
P =
6V =
t
1
OC
R3
10Ω
5
4356mp12 TA02
C
1μF
LT4356MP-1/LT4356MP-2
TMR
=
OUT
14V • 50mV
FLT
1.25V • R4 + R5
(
4
EN
FB
6V – 1.25V
47nF • 0.85V
10mΩ
10
11
2
45.5µA
1.25V
100μF
R5
(
V
OUT
= 70W
)
• R5
= 0.878ms
)
= 380k
CC
= 14V.
15
4356mp12f