ATA6025_05 Datasheet, PDF (1/13 Pages) ATMEL Corporation – Watchdog IC

Features
• Watchdog Adjustable
• Over- and Undervoltage Detection of V_cc = 5V
• Standby Modes On/Off via Ignition Pin VKL15
• Internal Time Delay for Output Signal
• Push-pull Output Driver
• Interference and Damage Protection According to ISO/CD 7637
• ESD Protection
Watchdog IC
1. Description
The ATA6025 is a monolithic circuit based on Atmel’s smart power BCD60-III technol-
ogy. It is a universal IC for monitoring basic functions of an automotive application. It
is possible to monitor the battery voltage (VKL15) and an external 5V voltage regula-
tor. With the independent watchdog the correct function of a microcontroller can be
observed. If a failure occurs, the output NOTL switches to high after a time delay. Dur-
ing standby mode the current consumption is reduced to a minimum.
Figure 1-1. Block Diagram
RREF
VB
VCC
VKL15
VBG
oscillator
on chip
trimming
BIAS
current
OSC
VCCH
VCC
over- & undervoltage
detection
VBG
IBias
standby mode
5V regulator
POR & Bandgap
Reference
VB monitoring
Short circuit _{2.5 mA}
protected
VDD
POR
VBOK
VCCL
VDD
NVKL15
up
&down
counter
400ms
NL High
at counter end
NL Low
at counter zero
failure
watchdog
fwd
POR
Watchdog
VDD
High at counter
zero
standby mode
OSC
OSC
Input
Test mode 1 or 2
divided by 4
NOTL
WD
CLK
GND
ATA6025
Rev. 4716C–AUTO–09/05