Hitachi H8/3692 ユーザーズマニュアル
Rev. 1.0, 07/01, page 265 of 372
Section 17 Power-on Reset and Low-Voltage Detection
Circuits (Optional)
This LSI includes a power-on reset circuit and low-voltage detection circuit.
The low-voltage detection circuit has two functions: one is to generate an interrupt when the
power-supply voltage falls below or rises above respective specified values, and this is called the
LVDI (interrupt by low voltage detect) function; the other is to reset the entire chip when the
power-supply voltage falls below a specified value, and this is called the LVDR (reset by low
voltage detect) function.
power-supply voltage falls below or rises above respective specified values, and this is called the
LVDI (interrupt by low voltage detect) function; the other is to reset the entire chip when the
power-supply voltage falls below a specified value, and this is called the LVDR (reset by low
voltage detect) function.
Figure 17-1 is a block diagram of the power-on reset circuit and the low-voltage detection circuit.
17.1
Features
•
Power-on reset circuit
Uses an external capacitor to generate an internal reset signal when power is first supplied.
•
Low-voltage detection circuit
Monitors the power-supply voltage, and generates an internal reset signal when the voltage
falls below a specified value, or generates an interrupt when the voltage falls lower or rises
above respective specified values.
falls below a specified value, or generates an interrupt when the voltage falls lower or rises
above respective specified values.
Two pairs of detection levels are available.
LVI0000A0000_000020010700