LTC4213 Linear Technology, LTC4213 Datasheet - Page 16

• Manufacturer Part Number: LTC4213
• Description: Electronic Circuit Breaker
• Manufacturer: Linear Technology

www.DataSheet4U.com
APPLICATIO S I FOR ATIO
LTC4213
Load Supply Power-Up Before V
Referring back to Figure 1, the V
powered up before V
gram with the V
circuit ensures that the GATE pin is held low. At time point
1, V
60µs later at time point 3, the GATE is ramped up with
100µA. At time point 4, GATE reaches the external MOSFET
threshold V
V
is armed and the circuit breaker can trip if ∆V
16
SENSEN
CC
clears UVLO and at time point 2, ON clears 0.8V.
is near its peak. At time point 6, the circuit breaker
TH
and V
IN
load supply active initially. An internal
U
OUT
CC
. Figure 5 shows the timing dia-
starts to ramp up. At time point 5,
V
V
V
V
V
U
CC
GATE
SENSEP
SENSEN
READY
, V
RESET MODE
ON
0
IN
CC
load supply can also be
1
W
V
CC
2
> 2.07V
Figure 5. Load Supply Power-Up Before V
t
DEBOUNCE
V
ON
> 0.8V
SENSE
U
3
> V
V
4
SENSEP
STARTUP CYCLE
CB
V
th
.
– V
SENSEN
CIRCUIT BREAKER ARMS
At time point 7, the GATE voltage peaks. 50µs after time
point 6, READY goes HIGH.
Startup Problems
There is no current limit monitoring during output charg-
ing for the figure 5 power-up sequence where the load
supply is powered up before V
voltage is below ∆V
the specified R
sufficient capability to handle the inrush as the output
charges up. For proper startup, the final load at time
= V
5
CB
6
V
t
READY
∆V
GATE
GSARM
NORMAL CYCLE
MAXES OUT
7
∆V
CC
DSON
GSMAX
+ V
8
SENSEN
GSARM
. The V
+ V
READY SIGNALS
SENSEN
4213 F05
and the MOSFET may not reach
IN
CC
load supply should have
. This is because the GATE
4213f