MAX6765–MAX6774
Automotive Micropower Linear Regulators
with Supervisor
9
Maxim Integrated
Pin Description (continued)
PIN
MAX6765/
MAX6766
MAX6767/
MAX6768
MAX6769/
MAX6770
MAX6771/
MAX6772
MAX6773/
MAX6773B/
MAX6774/
MAX6774B
NAME FUNCTION
—4———HOLD
Active-Low Regulator Hold Input. When HOLD is
forced low, OUT remains on even if ENABLE is pulled
low. To shut down the regulator, release HOLD after
ENABLE is pulled low. Connect HOLD to OUT or
leave unconnected if unused. HOLD is internally
connected to OUT through a 1.8µA current source.
— 6 6 6 6 SET
Feedback Input for Setting the Output Voltage.
Connect SET to GND to select the preset output
voltage. Connect to an external resistive divider for
adjustable output operation.
— — 4 — — RESETIN
Adjustable Reset Threshold Input. Connect to a
resistive divider to set the desired threshold.
— — — 3 — ENABLE1
Active-High Enable Input 1. Drive ENABLE1 high to
turn on the regulator. ENABLE1 is internally
connected to ground through a 0.6µA current sink.
— — — 4 — ENABLE2
Active-High Enable Input 2. Drive ENABLE2 high to
turn on the regulator. ENABLE2 is internally
connected to ground through a 0.6µA current sink.
———— 4WDI
Watchdog Timer Input. If WDI remains high or low for
longer than the watchdog timeout period, the
internal watchdog timer expires and the reset output
asserts for the reset timeout period. The internal
watchdog timer clears whenever a reset is asserted
or WDI sees a rising or falling edge. The watchdog
timer cannot be disabled. Do not leave WDI
unconnected.
———— —EP
Exposed Pad. EP is internally connected to GND.
Connect EP to the ground plane to provide a low
thermal-resistance path from the IC junction to the
PCB. Do not use as the electrical connection to GND.
Detailed Description
The MAX6765–MAX6774B low-quiescent-current, high-
voltage linear regulators operate from a 4V to 72V input
voltage and deliver more than 100mA of load current.
The MAX6765–MAX6774B include an integrated µP
reset circuit that monitors the regulator output voltage
and asserts a reset output when OUT falls below a
threshold limit, and includes an internally fixed or
adjustable reset timeout using a capacitor from TIME-
OUT to ground. All devices are available in a preset out-
put-voltage option of +1.8V, +2.5V, +3.3V, and +5V. The
output voltage of the MAX6767–MAX6774B is adjustable
from +1.8V to +11V using a resistive divider at SET. The
MAX6773/MAX6774 include a watchdog timer (WDI)
with a 1.6s (typ) watchdog timeout period and the
MAX6773B/MAX6774B include a watchdog timer with a
50ms (typ) watchdog timeout period. The MAX6769/
MAX6770 feature an adjustable reset threshold using a
resistive divider between the monitored voltage,
RESETIN, and GND; see the
Functional Diagrams
.
The MAX6771/MAX6772 provide dual enable inputs
(ENABLE1 and ENABLE2) to turn on and off the regula-
tor either through an ignition switch or a bus transceiver.
