STM704T/S/R STMicroelectronics, STM704T/S/R Datasheet - Page 9

• Manufacturer Part Number: STM704T/S/R
• Description: 3V Supervisor
• Manufacturer: STMicroelectronics

Specifications of STM704T/S/R

• Operating Temperature: –40 °C to 85 °C (industrial grade)

STM690, STM704, STM795, STM802, STM804, STM805, STM806
1.1
1.1.1
1.1.2
1.1.3
1.1.4
1.1.5
1.1.6
1.1.7
1.1.8
Pin descriptions
MR (manual reset)
A logic low on MR asserts the reset output. Reset remains asserted as long as MR is low
and for t
driven from a TTL or CMOS logic line, or shorted to ground with a switch. Leave open if
unused.
WDI (watchdog input)
If WDI remains high or low for 1.6 s, the internal watchdog timer runs out and reset is
triggered. The internal watchdog timer clears while reset is asserted or when WDI sees a
rising or falling edge.
The watchdog function cannot be disabled by allowing the WDI pin to float.
RST (active-low reset)
Pulses low for t
or when MR is a logic low. It remains low for t
threshold, the watchdog triggers a reset, or MR goes from low to high.
RST (active-high reset - open drain)
Pulses high for t
threshold or when MR is a logic high. It remains high for t
reset threshold, the watchdog triggers a reset, or MR goes from high to low.
PFI (power-fail input)
When PFI is less than V
PFO remains high. Connect to ground if unused.
PFO (power-fail output)
When PFI is less than V
high. Leave open if unused. Output type is push-pull.
V
When V
a P-channel MOSFET switch. When V
to V
Vccsw (V
When V
low. It can be used to drive gate of external PMOS transistor for I
exceeding 75 mA. Output type is push-pull.
OUT
CC
(supply output voltage)
if no battery is used.
OUT
CC
rec
is above the switchover voltage (V
after MR returns high. This active-low input has an internal pull-up. It can be
CC
switches to battery, Vccsw is high. When V
rec
switch output)
rec
when triggered, and stays low whenever V
when triggered, and stays high whenever V
PFI
PFI
, or V
or when V
Doc ID 10519 Rev 9
CC
falls below V
CC
CC
falls below V
falls below V
rec
SO
SW
), V
after either V
, PFO goes low; otherwise, PFO remains
OUT
SW
SO
OUT
is connected to V
, V
rec
(2.4 V), PFO goes low; otherwise,
BAT
switches back to V
after either V
CC
CC
CC
connects to V
is below the reset threshold
rises above the reset
OUT
is above the reset
requirements
CC
CC
falls below the
through
OUT
CC
Description
. Connect
, Vccsw is
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