SP691A Datasheet, PDF (15/24 Pages) Sipex Corporation – Low Power Microprocessor Supervisory with Battery Switch-Over

NAME
STATUS
PIN NUMBER
V
BATT
Supply
current
is
1µA
maximum
when
V <(V -1.2V).
CC
BATT
1
V_OUT
V_OUT connected to V_BATT through an internal PMOS switch.
2
V_CC
Battery switchover comparator monitors V_CC for active switchover. V_CC is
disconnected from V_OUT.
3
GND 0V reference for all signals.
4
BATT ON Logic HIGH. The open-circuit output voltage is equal to V_OUT.
5
LOWLINE Logic LOW.
6
OSC_IN OSC_IN is ignored and is at high-Z.
7
OSC_SEL OSC_SEL is ignored and is at high-Z.
8
PFI
The power-fail comparator is disabled.
9
PFO
The power-fail comparator is disabled. PFO is forced to logic LOW.
10
WDI
WDI is ignored and is at high-Z.
11
CE_OUT Logic HIGH. The open-circuit output voltage is equal to V_OUT.
12
CE_IN
High-Z.
13
WDO
Logic HIGH. The open-circuit output voltage is equal to V_OUT.
14
RESET Logic LOW.
15
RESET High-Z.
16
Table 2. Input and Output Status in Battery-Backup Mode; to enter the Battery-Backup Mode, V_CC must be less than the
reset threshold and less than V_BATT.
VBATT
VCC
SW1
D1 D2
SW2
VOUT
0.1µF
Figure 24. V_CC and V_BATT to V_OUT Switch
Input Supply Voltage
The Input Supply Voltage (VCC) should be a
regulated +5V source. VCC connects to VOUT
via a parallel diode and a large PMOS switch.
The switch carries the entire current load for
currents less than 250mA. The parallel diode
carries any current in excess of 250mA. Both
the switch and the diode have impedances
less than 1Ω each. Refer to Figure 24. The
maximum continuous current is 250mA, but
power-on transients may reach a maximum of 1A.
Backup-Battery Input
The Backup-Battery Input (VBATT) is similar
to VCC, except the PMOS switch and parallel
diode are much smaller. Refer to Figure 24.
Accordingly, the on-resistances of the diode and
the switch are each approximately 10Ω.
Date: 5/25/04
SP691A/693A/800L/800M Low Power Microprocessor Supervisor with Battery Switch-Over © Copyright 2004 Sipex Corporation
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