UPD16876 Datasheet, PDF (9/20 Pages) NEC – SINGLE Pch HIGH-SIDE SWITCH FOR USB

µPD16876
3. Behavior When Power Is Turned ON/OFF
This IC performs a soft-start operation on power application. This is to prevent an overcurrent from flowing
through the IC on power application while the high-capacity capacitor connected to the output pin is charged.
Power ON: Soft start (2.5 to 8 ms)
Power OFF: No control (10 µs MAX.)
5V
Vin
0V
5V
Vout
0V
2.5 ms MIN.
8 ms MAX.
10 µ s MAX.
The above figure does not show the actual waveform. For the related characteristic waveform, refer to Major
Characteristic Curves.
4. Output Latch Functional Change
LATCH = “H”: This IC has the control terminal (LATCH terminal) which latches the output current limitation after
over current detection.
An output latch function is explained below.
The output switch is turned off irrespective of the state of a CTL terminal after over current
detection.
Again, in order to make a switch into an ON state, it is necessary that a CTL terminal is setting to
Low level.
This function can be used, when you want to make a CTL terminal “L” fixation and to always
consider as an ON state, or when a USB controller to switch-ON/OFF control is unnecessary.
LATCH = “L”: A current limitation circuit operates after over current detection.
A limitation function is continued until the over current is eliminated.
After current detection, when abnormal condition is eliminated, output returns to an ON state.
This function serves as specification which suited USB specification.
Data Sheet S14288EJ1V0DS
9