LTC1643AL
LTC1643AL-1/LTC1643AH
APPLICATIONS INFORMATION
ON
10V/DIV
TIMER
10V/DIV
GATE
10V/DIV
12VOUT
5V/DIV
3VOUT
5V/DIV
5VOUT
5V/DIV
VEEOUT
5V/DIV
ON
10V/DIV
TIMER
10V/DIV
GATE
10V/DIV
12VOUT
5V/DIV
5VOUT
5V/DIV
3VOUT
5V/DIV
VEEOUT
5V/DIV
FAULT
10V/DIV
PWRGD
10V/DIV
FAULT
10V/DIV
PWRGD
10V/DIV
20ms/DIV
1643A F04
Figure 4. Power-Up into a Short on 3.3V Output
20ms/DIV
1643A F05
Figure 5. Short Circuit on 5V Followed by Circuit Breaker Reset
12
5V
R2
Q2
1 0.005Ω 2 IRF7413
3.3V
3
4
C2
R3
R5
1µF 20Ω 10Ω
R1
Q1
1 0.007Ω 2 IRF7413
3
4
R4 R6
20Ω 10Ω
C3
1µF
R7
100Ω
9
10
11
3
13
12
3VIN 3VSENSE GATE 3VOUT 5VIN 5VSENSE
14
5VOUT
LTC1643AL
1643A F06
5V
5A
3.3V
7.6A
C1
0.047µF
Figure 6. Delay in the Current Limit Loop
1643afa