快速浏览 - MAX696, MAX697 微处理器监控电路

快速浏览

技术文档

定购信息

更多信息

所有内容

概述

完整的数据资料 (PDF, 640kB)
英文下载

The MAX696/MAX697 supervisory circuits reduce the complexity and number of components required for power-supply monitoring and battery-control functions in microprocessor (µP) systems. These include µP reset and backup-battery switchover, watchdog timer, CMOS RAM write protection, and power-failure warning. The MAX696/MAX697 significantly improve system reliability and accuracy compared to that obtained with separate ICs or discrete components.

The MAX696 and MAX697 are supplied in 16-pin packages and perform six functions:
1) A reset output during power-up, power-down, and brownout conditions. The threshold for this "lowline" reset is adjustable by an external voltage-divider.
2) A reset pulse if the optional watchdog timer has not been toggled within a specified time.
3) Individual outputs for low-line and watchdog fault conditions.
4) The reset time may be left at its default value of 50ms, or may be varied with an external capacitor or clock pulses.
5) A separate 1.3V threshold detector for power-fail warning, low-battery detection, or to monitor a power supply other than V_CC.

The MAX696 also has battery-backup switching for CMOS RAM, CMOS microprocessor, or other low-power logic.

The MAX697 lacks battery-backup switching, but has write-protection pins (CE-bar IN and CE-bar OUT) for CMOS RAM or EPROM. In addition, it consumes less than 250 microamperes.

关键特性

应用/使用

Adjustable Low-Line Monitor and Power-Down Reset
Power-OK/Reset Time Delay
Watchdog Timer—100ms, 1.6s, or Adjustable
Minimum Component Count
1µA Standby Current
Battery-Backup Power Switching (MAX696)
On-Board Gating of Chip-Enable Signals (MAX697)
Separate Monitor for Power-Fail or Low-Battery Warning
通过美国保险商实验室协会(UL®)认证

	汽车系统
	计算机
	控制器
	精确的µP电源监控
	智能仪表

Key Specifications: Battery Backup Circuits

Part Number

Reset Threshold Range (V)

Active-Low Reset Output

Active-High Reset Output

Max. I_CC (µA)

Features

RoHS Available

Industry Qualified

Package

Smallest Available Package (max w/pins) (mm²)

Operating Temp. Range (°C)

Price^**

MAX696

1.2 to 1.8
1.8 to 2.5
2.5 to 3.3
3.3 to 5.5

Push-Pull

4000

•	Adjustable Reset Input

•	Battery On

•

Low Line

•	Power Fail Comparator

•

Watchdog

Yes

MIL-STD-883B

CDIP(N)/16
LCC/20
PDIP(N)/16
SOIC(W)/16

-55 to +125
-40 to +85
0 to +70

$3.55 @ 1k

See All Battery Backup Circuits (86)

Key Specifications: Supervisors (1 Monitored Voltage)

Part Number

Reset Threshold Range (V)

Active-Low Reset Output

Active-High Reset Output

Min. Reset Timeout Range

Watchdog Feature

Nom. Watchdog Timeout Range

Supervisor Features

Reset Thresh. Acc. (% @+25°C)

Max. I_CC (µA)

Price^**

MAX697

1.2 to 1.8
1.8 to 2.5
2.5 to 3.3
3.3 to 5.5

Push-Pull

1ms to 15ms
15ms to 85ms
85ms to 300ms
300ms to 1s
<1ms
>1s
Adjustable

Input (WDI)
Input/Output (WDI/WDO)

1s to 2s
<1s
>2s
Adjustable

Adjustable Reset Input
Power Fail Comparator

2.5

300

$3.58 @ 1k

See All Supervisors (1 Monitored Voltage) (270)

Notes:
^**This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific prices and delivery, please see the price and availability page or contact an authorized distributor.