ADM8693ARN Analog Devices Inc, ADM8693ARN Datasheet - Page 13

• Manufacturer Part Number: ADM8693ARN
• Description: IMPROVED ADM693 I.C.
• Manufacturer: Analog Devices Inc
• Type: Battery Backup Circuitr

Specifications of ADM8693ARN

• Rohs Compliant: NO
• Rohs Status: RoHS non-compliant
• Number Of Voltages Monitored: 1
• Output: Push-Pull, Push-Pull
• Reset: Active High/Active Low
• Reset Timeout: 35 ms Minimum
• Voltage - Threshold: 4.4V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)

POWER-FAIL WARNING COMPARATOR
An additional comparator is provided for early warning of
failure in the microprocessor power supply. The power-fail
input (PFI) is compared to an internal 1.3 V reference. The
power-fail output ( PFO ) goes low when the voltage at PFI is less
than 1.3 V. Typically, PFI is driven by an external voltage divider
that senses either the unregulated dc input to the system 5 V
regulator or the regulated 5 V output. The voltage divider ratio
can be chosen such that the voltage at PFI falls below 1.3 V
several milliseconds before the 5 V power supply falls below the
reset threshold. PFO is normally used to interrupt the
microprocessor so that data can be stored in RAM and the shut-
down procedure executed before power is lost.
POWER
INPUT
R1
R2
Figure 23. Power-Fail Comparator
POWER
INPUT
FAIL
1.3V
ADM869x
ADM8690/ADM8691/ADM8692/ADM8693/ADM8694/ADM8695
PFO
POWER
FAIL
OUTPUT
Rev. A | Page 13 of 20
Table 6. Input and Output Status in Battery Backup Mode
Signal
V
RESET
RESET
LOW LINE
BATT ON
WDI
WDO
PFI
PFO
CE
CE
OSC IN
OSC SEL
OUT
IN
OUT
Status
V
switch.
Logic low.
Logic high. The open-circuit output voltage is equal
to V
Logic low.
Logic high. The open-circuit voltage is equal to V
WDI is ignored. It is internally disconnected from the
internal pull-up resistor and does not source or sink
current as long as its input voltage is between GND
and V
current.
Logic high. The open circuit voltage is equal to V
The power-fail comparator is turned off and has no
effect on the power-fail output.
Logic low.
CE
internal pull-up and does not source or sink current
as long as its input voltage is between GND and
V
current.
Logic high. The open circuit voltage is equal to V
OSC IN is ignored.
OSC SEL is ignored.
OUT
OUT
IN
OUT
. The input voltage does not affect supply
is ignored. It is internally disconnected from its
is connected to V
OUT
.
. The input voltage does not affect supply
BATT
via an internal PMOS
OUT
OUT
OUT
.
.
.