R5101G001A RICOH [RICOH electronics devices division], R5101G001A Datasheet - Page 11

• Manufacturer Part Number: R5101G001A
• Description: Microprocessor power management with Watchdog Timer
• Manufacturer: RICOH [RICOH electronics devices division]

n OPERATION
¬
-
Regulator, V
until Voltage of the C
“H” level.
\
tPR can be set by connecting an external capacitor to C
tPR (ms)
®
the C
¯
C
°
of the pulse), the operation mode of C
the external capacitor connected to C
±
pulse to CLK pin, the voltage level of Reset pin becomes from “H” to “L”.
\
tWD can be set by connecting an external capacitor to C
tWD (ms)
²
\
to Vref2H. tWR can be calculated by the next equation as shown below;
tWR (ms)
³
´
watchdog timer is stopped and monitoring the output voltage is continued. After that, if the voltage level of CE
pin becomes to “H”, C
Rev. 1.10
becomes “L” level.
reverse the voltage level of V
output voltage of the Voltage Regulator drops to a level at equal or less than -Vdet.
TW
tPR : Time interval between the timing of starting edge of forcing voltage to VDD pin and the timing of
Watch Time of the watchdog timer , tWD , : Discharging Time of C
Reset time of the watchdog timer , tWR , : Time interval between Charging time of the C
When V
The operation mode for
While the C
C
The Output Voltage level of Reset pin becomes from “H” to “L”, or a Reset signal is generated when an
When the voltage level of V
While the C
The watchdog timer will be halted when a Voltage level of CE pin becomes to “L”. In this case, only the
An External Capacitor starts to be charged through the C
TW
pin when the voltage level of C
TW
pin is changed to charging mode from discharging mode when the Reset signal is generated.
pin and the watchdog timer begins to operate.
»
»
»
DD
13000
10000
tWD/10
OUT
is turned on and Input Voltage reaches Vstart (nearly equal 0.8V), the output of RESET pin
TW
TW
, crosses the Released Voltage , +V
´
pin is on the discharging mode, if a clock pulse is entered (synchronous with a rising edge
´
pin is on the discharging mode, if VCTW level drops to Vref2L, about 0.2V without clock
C
C
D
D
W
TW
pin , V
(
m
(
F) ; C
m
pin starts to be on charging mode.
F);
t
he external capacitor changes from charging mode to discharging mode through
CD
Cw means a value of an external capacitor connected to Cw pin.
RESET
D means a value of an external capacitor connected to C
CD
, reaches to the Vref2H , about 1.0V , and after that the V
reaches to the Vref2H, the external capacitor starts to be charged through
TW
.
TW
TW
pin , V
pin is charged until its voltage level reaches to Vref2H.
pin changes from charging mode to discharging mode. And
CTW
- 11 -
, reaches to the Vref2H.
DET
D
W
, from Lower to Higher . The V
pin, tPR can be calculated as shown below;
pin, tWD can be calculated as shown below;
D
pin when an Output Voltage of the Voltage
TW
pin level from Vref2H to Vref2L
D
pin.
RESET
RESET
TW
12345
pin from Vref2L
is kept “L” level
becomes to