onsemi CAT1026YI-30-GT3

The CAT1026 and CAT1027 are complete memory and supervisory solutions for microcontroller-based systems. A 2k-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 400kHz I²C bus. The CAT1026 and CAT1027 provide a precision VCC sense circuit with five reset threshold voltage options that support 5V, 3.3V and 3V systems. The power supply monitor and reset circuit protects memory and systems controllers during power up/down and against brownout conditions. If power supply voltages are out of tolerance reset signals become active preventing the system microcontroller, ASIC, or peripherals from operating. The CAT1026 features two open drain reset outputs: one (RESET) drives high and the other (¯R¯E¯S¯E¯T¯) drives low whenever VCC falls below the threshold. Reset outputs become inactive typically 200ms after the supply voltage exceeds the reset threshold value. With both active high and low reset signals, interface to microcontrollers and other ICs is simple. CAT1027 has only a ¯R¯E¯S¯E¯T¯ output. In addition, the ¯R¯E¯S¯E¯T¯ pin can be used as an input for push-button manual reset capability. The CAT1026 and CAT1027 provide an auxiliary voltage sensor input, VSENSE, which is used to monitor a second system supply. The auxiliary high impedance comparator drives the open drain output, VLOW, whenever the sense voltage is below 1.25V threshold. The CAT1027 is designed with 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 CAT1027 features a watchdog timer interrupt input, WDI. The on-chip 2k-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 8-pin DIP and surface mount, 8-pin SO, 8-pin TSSOP, 8-pin TDFN and 8-pin MSOP packages. The TDFN package thickness is 0.8mm maximum. TDFN footprint is 3x3mm.

• Precision VCC Power Supply Voltage Monitor — 5 V, 3.3 V and 3 V systems — Five threshold voltage options
• Additional voltage monitoring — Externally adjustable down to 1.25 V
• Watchdog timer (CAT1027 only)
• Active High or Low Reset — Valid reset guaranteed at VCC = 1 V
• 400 kHz I2C Bus
• 2.7 V to 5.5 V Operation
• Low power CMOS technology
• 16-Byte Page Write Buffer
• Built-in inadvertent write protection
• 1,000,000 Program/Erase cycles
• Manual Reset capability
• 100 year data retention
• Industrial and extended temperature ranges
• 8-pin DIP, SOIC, TSSOP, MSOP or TDFN (3x3mm foot-print) packages — TDFN max height is 0.8mm