MAX16023/MAX16024
Battery-Backup Circuits with
Regulated Output Voltage
8 _______________________________________________________________________________________
Pin Description
PIN
MAX16023 MAX16024
NAME FUNCTION
12V
CC
Supply Voltage Input. Bypass V
CC
to GND with a 0.1µF capacitor.
2 3 BATT
Backup Battery Input. If V
CC
falls below its reset threshold (V
TH
), V
BATT
≥ V
CC
, and if
the regulator enters dropout, the regulator is powered from BATT. If V
BATT
< V
CC
,
the regulator is powered from V
CC
. Bypass BATT to GND with a 0.1µF capacitor.
34MR
Active-Low, Manual-Reset Input. RESET asserts when MR is pulled low. RESET
remains low for the duration of reset timeout period after MR transitions from low to
high. Connect MR to OUT or leave unconnected if not used. MR is internally
connected to V
CC
through a 30kΩ pullup resistor.
4 — PFI
Power-Fail Comparator Input. Connect PFI to a resistive divider to set the desired PFI
threshold. The PFI input is referenced to an internal V
PFT
threshold. A V
PFI-HYS
internal hysteresis provides noise immunity. The power-fail comparator is powered
from OUT.
5—PFO
Active-Low, Power-Fail Comparator Output. PFO goes low when V
PFI
falls below the
internal V
PFT
threshold and goes high when V
PFI
rises above V
PFT
+ V
PFI-HYS
hysteresis.
6 7 GND Ground
78RESET
Active-Low Reset Output. RESET asserts when V
CC
falls below the reset threshold or
MR is pulled low. RESET remains low for the duration of the reset timeout period after
V
CC
rises above the reset threshold and MR goes high. RESET is available in push-
pull and open-drain options.
8 9 OUT
Linear Regulator Output Voltage. Available in the following factory-fixed voltages of
1.2V, 1.8V, 2.5V, 3.0V, or 3.3V for all devices. The MAX16024 is also available with
an adjustable output voltage (1.8V to 5.25V). Bypass OUT to GND with a 10µF
capacitor.
—1CEIN
Chip-Enable Input. The input to CE gating circuitry. Connect to GND or OUT if not
used.
— 5 SET
Set Output Voltage Input. For the fixed output voltage versions (MAX16024_TB_ _ _),
SET is not used. Connect SET to GND. For MAX16024_TB_, connect SET to an
external resistive divider to set the desired output voltage between 1.8V and 5.25V.
— 6 BATT ON
Active-High, Battery-On Output. BATT ON goes high when in the battery backup
mode.
—10CEOUT
Active-Low, Chip-Enable Output. CEOUT goes low only when CEIN is low and reset
is not asserted. If CEIN is low when reset is asserted, CEOUT stays low for 12µs (typ)
or until CEIN goes high, whichever occurs first.
——EP
Exposed Pad. Internally connected to GND. Connect EP to a large ground plane to
aid heat dissipation. Do not use EP as the only ground connection for the device.
