CAT1021: CPU Supervisor with 2 k EEPROM Memory

The CAT1021 is a complete memory and supervisory solution for microcontroller based systems. A 2 k-bit serial EEPROM memory and a system power supervisor with brown-out protection are integrated together in low power CMOS technology. Memory interface is via a 400 kHz I²C bus.The CAT1021 provides a precision VCC sense circuit and two open drain outputs: one (RESET) drives high and the other (RESET) drives low whenever VCC falls below the reset threshold voltage. The CAT1021 also has a Write Protect input (WP). Write operations are disabled if WP is connected to a logic high.The supervisor has a 1.6 second watchdog timer circuit that resets a system to a known state if software or a hardware glitch halts or 'hangs' the system. The watchdog timer monitors the SDA signal.The power supply monitor and reset circuit protect memory and system controllers during power up/down and against brownout conditions. Five reset threshold voltages support 5.0 V, 3.3 V and 3.0 V systems. If power supply voltages are out of tolerance reset signals become active, preventing the system microcontroller, ASIC or peripherals from operating. Reset signals become inactive typically 200 ms after the supply voltage exceeds the reset threshold level. With both active high and low reset signals, interface to microcontrollers and other ICs is simple. In addition, the RESET pin or a separate input, MR, can be used as an input for push-button manual reset capability.The on-chip, 2 k-bit EEPROM memory features a 16-byte page. In addition, hardware data protection is provided by a VCC sense circuit that prevents writes to memory whenever VCC falls below the reset threshold or until VCC reaches the reset threshold during power up.Available packages include an 8-pin DIP, 8-pin SOIC, 8-pin TSSOP, 8-pin TDFN and 8-pin MSOP. The TDFN packa

Features
  • Precision power supply voltage monitor - 5.0 V, 3.3 V and 3.0 V systems - Five threshold voltage options
  • Watchdog timer
  • Active high or low reset - Valid reset guaranteed at VCC = 1 V
  • 400 kHz I²C bus
  • 3.0 V to 5.5 V operation
  • Low power CMOS technology
  • 16-Byte page write buffer
  • Built-in inadvertent write protection — WP pin
  • 1,000,000 Program/Erase cycles
  • Manual reset input
  • 100 year data retention
  • 8-pin DIP, SOIC, TSSOP, MSOP or TDFN (3 x 3 mm foot-print) packages — TDFN max height is 0.8mm
  • Industrial and extended temperature ranges
Applications
  • Industrial control
  • Medical systems
  • Printers
  • Mass storage
Data Sheets (1)
Document TitleDocument ID/SizeRevisionRevision Date
Supervisory Circuits with I²C Serial 2k-bit CMOS EEPROM, Manual Reset and Watchdog TimerCAT1021/D (187.0kB)18
Package Drawings (5)
Document TitleDocument ID/SizeRevision
MSOP 8, 3x3846AD (56.5kB)revo
PDIP-8, 300 mils646AA (55.8kB)A
SOIC 8, 150 mils751BD (55.6kB)revo
TDFN8, 3x3511AL (55.4kB)A
TSSOP8, 4.4x3948AL (55.7kB)revo
Order Information
ProductStatusCompliancePackageMSL*ContainerBudgetary Price/Unit
CAT1021LI-25-GLifetimePb-free Halide freePDIP-8646AANATube50$0.8866
CAT1021LI-28-GLifetimePb-free Halide freePDIP-8646AANATube50$0.8866
CAT1021LI-30-GLifetimePb-free Halide freePDIP-8646AANATube50$0.8866
CAT1021LI-42-GLifetimePb-free Halide freePDIP-8646AANATube50$0.2825
CAT1021LI-45-GLifetimePb-free Halide freePDIP-8646AANATube50$0.8866
CAT1021WI-25-GLast ShipmentsPb-free Halide freeSOIC-8751BD1Tube100
CAT1021WI-25-GT3ActivePb-free Halide freeSOIC-8751BD1Tape and Reel3000$0.78
CAT1021WI-28-GActivePb-free Halide freeSOIC-8751BD1Tube100$0.8666
CAT1021WI-28-GT3ActivePb-free Halide freeSOIC-8751BD1Tape and Reel3000$0.78
CAT1021WI-30-GActivePb-free Halide freeSOIC-8751BD1Tube100$0.8666
CAT1021WI-30-GT3ActivePb-free Halide freeSOIC-8751BD1Tape and Reel3000$0.78
CAT1021WI-42-GActivePb-free Halide freeSOIC-8751BD1Tube100$0.8666
CAT1021WI-42-GT3ActivePb-free Halide freeSOIC-8751BD1Tape and Reel3000$0.78
CAT1021WI-45-GActivePb-free Halide freeSOIC-8751BD1Tube100$0.8666
CAT1021WI-45-GT3ActivePb-free Halide freeSOIC-8751BD1Tape and Reel3000$0.78
CAT1021YI-25-GActivePb-free Halide freeTSSOP-8948AL1Tube100$0.8666
CAT1021YI-25-GT3ActivePb-free Halide freeTSSOP-8948AL1Tape and Reel3000$0.78
CAT1021YI-28-GT3ActivePb-free Halide freeTSSOP-8948AL1Tape and Reel3000$0.78
CAT1021YI-30-GT3ActivePb-free Halide freeTSSOP-8948AL1Tape and Reel3000$0.78
CAT1021YI-42-GActivePb-free Halide freeTSSOP-8948AL1Tube100$0.8666
CAT1021YI-42-GT3ActivePb-free Halide freeTSSOP-8948AL1Tape and Reel3000$0.78
CAT1021YI-45-GT3ActivePb-free Halide freeTSSOP-8948AL1Tape and Reel3000$0.78
CAT1021ZD4I-25T3Consult Sales OfficePb-free Halide freeTDFN-8511AL1Tape and Reel3000
CAT1021ZD4I-28T3Consult Sales OfficePb-free Halide freeTDFN-8511AL1Tape and Reel3000
CAT1021ZD4I-30T3Consult Sales OfficePb-free Halide freeTDFN-8511AL1Tape and Reel3000
CAT1021ZD4I-42T3Consult Sales OfficePb-free Halide freeTDFN-8511AL1Tape and Reel3000
CAT1021ZD4I-45T3Consult Sales OfficePb-free Halide freeTDFN-8511AL1Tape and Reel3000
CAT1021ZI-25-GT3ActivePb-free Halide freeMSOP-8846AD1Tape and Reel3000$0.9066
CAT1021ZI-28-GT3ActivePb-free Halide freeMSOP-8846AD1Tape and Reel3000$0.9066
CAT1021ZI-30-GT3ActivePb-free Halide freeMSOP-8846AD1Tape and Reel3000$0.9066
CAT1021ZI-42-GActivePb-free Halide freeMSOP-8846AD1Tube96$0.9066
CAT1021ZI-42-GT3ActivePb-free Halide freeMSOP-8846AD1Tape and Reel3000$0.9066
CAT1021ZI-45-GT3ActivePb-free Halide freeMSOP-8846AD1Tape and Reel3000$0.9066
Specifications
ProductTypeDensityOrganizationData Transmission Standardfcycle Max (kHz)tACC Max nsVCC Min (V)VCC Max (V)Istandby Max (µA)Iact Max (mA)T Min (°C)T Max (°C)
CAT1021WI-25-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021WI-28-GSerial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021WI-28-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021WI-30-GSerial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021WI-30-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021WI-42-GSerial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021WI-42-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021WI-45-GSerial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021WI-45-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021YI-25-GSerial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021YI-25-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021YI-28-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021YI-30-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021YI-42-GSerial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021YI-42-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021YI-45-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021ZI-25-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021ZI-28-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021ZI-30-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021ZI-42-GSerial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021ZI-42-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
CAT1021ZI-45-GT3Serial2 kb256 x 8I2C4009002.75.5603-4085
Supervisory Circuits with I²C Serial 2k-bit CMOS EEPROM, Manual Reset and Watchdog Timer (187.0kB) CAT1021
PDIP-8, 300 mils CAT93C86B
SOIC 8, 150 mils CAV93C86
TSSOP8, 4.4x3 PCA9306
TDFN8, 3x3 CAT1027
MSOP 8, 3x3 CAT25010