sh6631a SinoWealth Micro-Electronics Corp. Ltd, sh6631a Datasheet - Page 12

• Manufacturer Part Number: sh6631a
• Description: Mask 4-bit Microcontroller
• Manufacturer: SinoWealth Micro-Electronics Corp. Ltd

Reset
LPD
2.5v
V
V
4.5v
LPDH
LPDL
11. Low Power Detection (LPD)
The LPD function monitors the supply voltage and applies an internal reset in the micro-controller at battery replacement. If the
applied circuit satisfies the following conditions, the LPD can be incorporated by the software control.
Functions of LPD Circuit:
The LPD circuit has the following functions:
V
the LPD reset will delay about 1ms before being triggered. If V
LPD reset.
LPD Control Register
The LPD circuit is controlled by the software enable flag.
V
LPDX
DD
Address
If high reliability is not required.
If power supply voltage is V
If operating ambient temperature is T
Generates an internal reset signal when V
Cancels the internal reset signal when V
Stops the oscillator operation and force the CPU to enter STOP mode when V
Below: V
$15
is always in range of CPU operating, therefore, there no malfunction occurs when V
DD
LPD3
: power supply voltage, V
Bit3
LPD2
Bit2
DD
= 2.2 TO 3.6V
LPD1
Bit1
1ms
LPDL
A
= −20 ℃ to + 70 ℃
DD
: POWERDOWN LPD-detect voltage, V
DD
LPD0
> V
Bit0
≤ V
LPDH
LPDL
( ≈ 2.1V).
( ≈ 1.7V).
R/W
W
DD
12
goes back to V
LPD Enable Control (LPD3 ~ 0):
0101: LPD Enable (Power-on initial)
1010: LPD Disable
DD
DD
＞ V
≤ V
LPDH
LPDH
Remarks
LPDL
: Power rise LPD-detect voltage.
LPDX
, without any delay then cancel the
.
is reached. As V
SH6631A
DD
≦ V
LPDL
,