R1215D002F RICOH [RICOH electronics devices division], R1215D002F Datasheet - Page 13

• Manufacturer Part Number: R1215D002F
• Description: STEP-UP DC/DC CONTOLLER
• Manufacturer: RICOH [RICOH electronics devices division]

<Latch Protection Operation>
maximum duty cycle, charge to an external capacitor, C2 of DELAY pin starts. The maximum duty cycle
continues and the voltage of DELAY pin reaches delay voltage detector threshold, V
and turns off the external power MOSFET.
and make it rise up to the normal input voltage.
charging the capacitor stops immediately, and the DELAY pin voltage is fixed at GND level with I
the next formula.
The operation of Latch protection circuit is as follows: When AMPOUT becomes "H" and the IC detects
Once after becoming the maximum duty cycle, if the duty cycle decreases before latch operation works, the
The delay time of latch protection can be calculated with C2, V
t=C2 × V
To release the latch protection operation, make the supply voltage down to UVLO detector threshold or lower,
DLY
/I
DLY1
Normal
Output Short
V
I
DLY1
DLY
DELAY
C2
Maxduty Operation
DLY
, and the delay pin charge current, I
Latched
DLY
V
DLY
, outputs "L" to EXT pin
DTC
DELAY
AMPOUT
DLY2
EXT
.
R1215D
DLY1
, as in
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