X4285

Preliminary Information 128K X4283/85 CPU Supervisor with 128K EEPROM DESCRIPTION 16K x 8 Bit FEATURES Selectable watchdog timer Low VCC detection and reset assertion —Four standard reset threshold voltages —Adjust low VCC reset threshold voltage using special programming sequence —Reset signal valid to VCC = 1V Low power CMOS —<20µA max standby current, watchdog on —<1µA standby current, watchdog OFF —3mA active current 128Kbits of EEPROM —64 byte page write mode —Self-timed write cycle —5ms write cycle time (typical) Built-in inadvertent write protection —Power-up/power-down protection circuitry —Protect 0, 1/4, 1/2, all or 64, 128, 256 or 512 bytes of EEPROM array with programmable Block Lock™ protection www.DataSheet4U.com 400kHz 2-wire interface 2.7V to 5.5V power supply operation Available packages —8-lead SOIC —8-lead TSSOP BLOCK DIAGRAM Watchdog Transition Detector WP Data Register Command Decode & Control Logic VCC Threshold Reset logic Block Lock Control Protect Logic The X4283/85 combines four popular functions, Power-on Reset Control, Watchdog Timer, Supply Voltage Supervision, and Block Lock protect serial EEPROM memory in one package. This combination lowers system cost, reduces board space requirements, and increases reliability. Applying power to the device activates the power on reset circuit which holds RESET/RESET active for a period of time. This allows the power supply and oscillator to stabilize before the processor can execute code. ...