Or, solved in terms of R1:

Unused Inputs

The unused inputs (except the adjustable) are internally

connected to ground through the lower resistors of the

threshold-setting resistor pairs. The adjustable input,

however, must be connected to ground if unused.

Reset Output

drops below its specified threshold or MR asserts low

and remains low for the reset timeout period (140ms

(Figure 8). The output is open drain with a weak (10µA)

nal pullup resistor is required to interface with other

logic devices. An external pullup resistor to any voltage

from 0 to 5.5V overdrives the internal pullup if interfac-

ing to different logic supply voltages (Figure 9). Internal

circuitry prevents reverse current flow from the external

Manual Reset Input

Many µP-based products require manual reset capabili-

ty, allowing the operator, a test technician, or external

logic circuitry to initiate a reset. A logic low on MR

asserts RESET low. RESET remains asserted while MR is

low, and during the reset timeout period (140ms min)

after MR returns high. The MR input has an internal 20k

Ω

Drive MR with TTL or CMOS-logic levels, or with open-

drain/collector outputs. Connect a normally open momen-

tary switch from MR to GND to create a manual reset

function; external debounce circuitry is not required. If

MR is driven from long cables or if the device is used in a

noisy environment, connecting a 0.1µF capacitor from

MR to GND provides additional noise immunity.

Reseting the µP from a 2nd Voltage

(MAX6714)

The MAX6714 can be configured to assert a reset from a

second voltage by connecting the power-fail output to

goes low and asserts the reset output for the reset time-

out period after the manual reset input is deasserted.

(See Typical Operating Circuit.)

Power-Supply Bypassing and Grounding

The MAX6709/MAX6714 operate from a single 2.0V to

Low-Voltage, High-Accuracy, Quad Voltage

Monitors in µMAX Package

10

______________________________________________________________________________________

R1 = R2

(

- 1

)

0.62V

R2

R1

Figure 7. Setting the Auxiliary Monitor

90%

10%

RESET

GND

5V

MAX6714

GND

RESET

RESET

100k

Ω

Figure 9. Interfacing to Different Logic Supply Voltage