STM6502 datasheet(12/29 Pages) STMICROELECTRONICS

12 / 29 page

Description

STM6502, STM6503, STM6504, STM6505

12/29

Doc ID 16101 Rev 5

1.2.7

Programmable Smart Reset input delay (TSR pin) – STM6503 and

STM6504 only

The TSR pin allows the user to program the setup time before the push-button action is

validated by the reset output. It is controlled by different voltage levels on the three-state

TSR input pin: when connected to ground, tSRC = 2 s; when left open, tSRC = 6 s; when

connected to VCC, tSRC = 10 s (all times are minimum). TSR is a DC-type input, intended to

be either permanently grounded, permanently connected to VCC or permanently left open.

If it is left open, for improved system glitch immunity it is strongly recommended to connect

a 0.1 µF decoupling ceramic capacitor between the TSR and VSS pins.

1.2.8

Reset output (RST)

RST is the active-low, open-drain reset output in the Smart Reset family.

1.2.9

Battery monitoring input (VBAT) – STM6505 only

VBAT is an input for monitoring the battery voltage. VBAT threshold is 1.25 V, fixed, and an

external resistor divider is to be used to set the actual battery voltage threshold.

1.2.10

Battery low detect output (BLD) – STM6505 only

The battery low detect output is controlled by the VBAT voltage monitoring input and is

active-low, open-drain, with no pull-up.

Figure 9.

STM6505 timing

AM00329

RST

BLD

SR0

SR1

tSRC

tREC

VBAT

VBATTH

STM6502 Datenblatt(PDF) 12 Page - STMicroelectronics