STM6905

Pin descriptions

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2

Pin descriptions

2.1

Push-button reset input (MR)

When MR goes low the RST output is driven low, RST remains low as long as MR is low and

not required. (If MR is driven from long cables or if the device is used in noisy environments,

2.2

selectable, factory programmed) reset thresholds include 3.078 V to 2.866 V.

2.3

V2IN second fixed voltage monitoring input

The V2IN input is the second fixed-voltage input for reset threshold monitoring. Available

fixed (customer-selectable, factory programmed) reset thresholds include 2.333 V to

1.050 V.

2.4

This pin is the ground pin for the power supply.

2.5

V3IN, V4IN, and V5IN

The V3IN, V4IN and V5IN are high impedance inputs. RST is driven low when the voltage

(VTRIP) at the pin falls below 600 mV (internal reference voltage at their respective

comparators). The monitored voltage reset threshold is set with an external resistor-divider

network.

2.6

RST active-low, open drain reset output

V4IN, or V5IN falls below its factory-trimmed or adjustable reset threshold or when MR

goes to logic low. It remains low for trec after all supply voltages being monitored rise above

their reset thresholds and MR goes from low to high. Connect an external pull-up resistor to