DS1836

www.maxim-ic.com DS1836/A/B/C/D 3.3V/5V MicroManager FEATURES ƒ 5V or 3.3V power-on reset ƒ True 3V operation power switch ƒ Switches to battery at 3.8V (2.6V for 3.3V versions) ƒ Excellent for systems designed to operate with dual power supplies ƒ Asserts resets during power transients ƒ Maintains reset for 350ms after VCC returns to an in-tolerance condition ƒ Reduces need for discrete components ƒ Precision temperature-compensated voltage reference and voltage sensor ƒ 8-pin DIP or space saving 8-pin SO surface mount available ƒ CMOS reset output for low current operation ƒ Operating temperature of -40°C to +85°C ƒ Perfect for PIC microprocessor applications PIN ASSIGNMENT VCC 1 8 RST(*RST) VBAT 2 7 NMI NC 3 6 IN VOUT 4 5 GND 8-Pin DIP (300mil) VCC 18 RST(*RST) VBAT 27 NMI NC 36 IN VOUT 45 GND 8-Pin SO (150mil) DS1836A/C (*DS1836B/D) PIN DESCRIPTION VCC VBAT NC - Power Supply Input - Battery Supply Input - No Connect VOUT GND - Power Supply Output - Ground IN - Sense Input NMI - Non-maskable Interrupt RST (*RST) - Reset Output DESCRIPTION The DS1836 MicroManager performs three vital system functions. First, a precision temperaturecompensated reference and comparator circuit monitor the status of the voltage on VCC and when an outof-tolerance condition is detected, an internal power-fail signal is generated that forces the reset active. If VCC continues to degrade, it switches to the battery supply when VCC drops below 3.8V (2.6V for 3....