UPD78F0838 Renesas Electronics Corporation., UPD78F0838 Datasheet - Page 778

• Manufacturer Part Number: UPD78F0838
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

23.1 Functions of Power-on-Clear Circuit
776
The power-on-clear circuit (POC) has the following functions.
Generates internal reset signal at power on.
In the 1.59 V POC mode (option byte: LVISTART = 0), the reset signal is released when the supply voltage
(V
In the 2.7 V/1.59 V POC mode (option byte: LVISTART = 1), the reset signal is released when the supply
voltage (V
Compares supply voltage (V
when V
Caution If an internal reset signal is generated in the POC circuit, the reset control flag register (RESF)
Remark The 78K0/Dx2 incorporates multiple hardware functions that generate an internal reset signal. A flag
DD
) exceeds 1.59 V 0.15 V.
DD
DD
< V
is cleared to 00H.
that indicates the reset cause is located in the reset control flag register (RESF) for when an internal
reset signal is generated by the watchdog timer (WDT) or low-voltage-detector (LVI). RESF is not
cleared to 00H and the flag is set to 1 when an internal reset signal is generated by WDT or LVI.
For details of RESF, see CHAPTER 21 RESET FUNCTION.
) exceeds 2.7 V 0.2 V.
POC
.
CHAPTER 23 POWER-ON-CLEAR CIRCUIT
DD
) and detection voltage (V
Preliminary User’s Manual U19748EJ1V0UD
POC
= 1.59 V 0.15 V), generates internal reset signal