MAX6730 Maxim, MAX6730 Datasheet - Page 7

• Manufacturer Part Number: MAX6730
• Description: Single-/Dual-/Triple-Voltage P Supervisory Circuits with Independent Watchdog Output
• Manufacturer: Maxim

MAX6730
MAX6731
—
—
1
2
3
4
5
6
Circuits with Independent Watchdog Output
MAX6732
MAX6733
Single-/Dual-/Triple-Voltage µP Supervisory
PIN
—
—
1
2
3
5
6
4
_______________________________________________________________________________________
MAX6734
MAX6735
1
2
4
5
3
8
6
7
NAME
RSTIN
WDO
V
V
GND
RST
WDI
MR
CC
CC
1
2
Active-Low Reset Output. The MAX6730/MAX6732/MAX6734 provide an open-
drain output. The MAX6731/MAX6733/MAX6735 provide a push-pull output. RST
asserts low when any of the following conditions occur: V
its preset threshold, RSTIN drops below its reset threshold, or MR is driven low.
Open-drain versions require an external pullup resistor.
Ground
Active-Low Watchdog Output. The MAX6730/MAX6732/MAX6734 provide an open-
drain WDO output. The MAX6731/MAX6733/MAX6735 provide a push-pull WDO
output. WDO asserts low when no low-to-high or high-to-low transition occurs on
WDI within the watchdog timeout period (t
condition exists for V
when V
reset input is deasserted. Open-drain versions require an external pullup resistor.
Active-Low Manual Reset Input. Drive MR low to force a reset. RST remains
asserted as long as MR is low and for the reset timeout period after MR releases
high. MR has a 50kΩ pullup resistor to V
unused.
Watchdog Input. If WDI remains high or low for longer than the watchdog timeout
period, the internal watchdog timer expires and the watchdog output asserts low.
The internal watchdog timer clears whenever RST asserts or a rising or falling edge
on WDI is detected. The watchdog has an initial watchdog timeout period (35s min)
after each reset event and a short timeout period (1.12s min) after the first valid
WDI transition. Floating WDI does not disable the watchdog timer function.
Primary Supply Voltage Input. V
than V
Secondary Supply Voltage Input. V
greater than V
Undervoltage Reset Comparator Input. RSTIN provides a high-impedance
comparator input for the adjustable reset monitor. RST asserts low if the voltage at
RSTIN drops below the 626mV internal reference voltage. Connect a resistive
voltage-divider to RSTIN to monitor voltages higher than 626mV. Connect RSTIN to
V
CC
1 or V
CC
CC
2. V
1, V
CC
2 if unused.
CC
CC
CC
1 is the input to the primary reset threshold monitor.
2, and RSTIN exceed their reset thresholds, or when the manual
1. V
CC
CC
1, V
2 is the input to the secondary reset threshold monitor.
CC
2, or RSTIN. WDO deasserts without a timeout period
CC
1 provides power to the device when it is greater
CC
FUNCTION
2 provides power to the device when it is
CC
WD
1; leave MR open or connect to V
) or if an undervoltage lockout
Pin Description
CC
1 or V
CC
2 drops below
CC
1 if
7