LTC693CSW

• Product Introduction

LTC693CSW Microprocessor monitoring circuitry

peculiarity

• 保证复位确定 (在 V_CC = 1V)
• 1.5mA 最大电源电流
• RAM 芯片使能信号的快速 (最大 35ns) 板上选通
• 4.40V 精准电压监视器
• 电源运行正常/复位延时：200ms 或可调
• 最少的外部元件数目
• 1μA 最大待机电流
• 用于电源故障或低电池电量报警的电压监视器
• 热限制
• 规定了整个温度范围内的性能
• MAX690 系列的卓越升级产品
• 采用 SO8 和 SO16 封装
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description

The LTC®692/LTC693 provide full power monitoring and battery control capabilities for microprocessor reset, battery backup, CMOS RAM write protection, power failure alarm, and watchdog timing. A precise internal voltage reference and comparator circuit monitors the power lines. When the tolerance range is exceeded, the reset output will be forced into an operating state, and the chip enable output will unconditionally write protect the external memory. In addition, the RESET output will be guaranteed to be logically low, even when VCC is as low as 1V.

The LTC692/LTC693 utilize a charge pump NMOS power switch to power the active CMOS RAM for low dropout and low supply current. When the main power supply is lost, a high-efficiency PMOS switch is used by the auxiliary power supply (to the battery input pin) to power the RAM in standby mode.

To provide early warning in the event of an impending power failure, the LTC692/LTC693 provide an internal comparator with user-defined thresholds. An internal watchdog timer is also provided that will force the reset pin to enter the running state when the watchdog input has not been transformed before a preset timeout period.