M41ST85W Datasheet | STMicroelectronics

FEATURES SUMMARY s 5.0 OR 3.0V OPERATING VOLTAGE s s SERIAL INTERFACE SUPPORTS I2C BUS (400 KHz) NVRAM SUPERVISOR FOR EXTERNAL LPSRAM OPTIMIZED FOR MINIMAL INTERCONNECT TO MCU 2.5 TO 5.5V OSCILLATOR OPERATING VOLTAGE AUTOMATIC SWITCH-OVER and DESELECT CIRCUITRY CHOICE OF POWER-FAIL DESELECT VOLTAGES - M41ST85Y: VCC = 4.5 to 5.5V; 4.20V ≤ VPFD ≤ 4.50V - M41ST85W: VCC = 2.7 to 3.6V; 2.55V ≤ VPFD ≤ 2.70V 1.25V REFERENCE (for PFI/PFO) COUNTERS FOR TENTHS/HUNDREDTHS OF SECONDS, SECONDS, MINUTES, HOURS, DAY, DATE, MONTH, YEAR, and CENTURY 44 BYTES OF GENERAL PURPOSE RAM PROGRAMMABLE ALARM and INTERRUPT FUNCTION (VALID EVEN DURING BATTERY BACK-UP MODE) WATCHDOG TIMER MICROPROCESSOR POWER-ON RESET BATTERY LOW FLAG POWER-DOWN TIMESTAMP (HT BIT) ULTRA-LOW BATTERY SUPPLY CURRENT OF 500n A (MAX) PACKAGING INCLUDES A 28-LEAD SOIC and SNAPHAT® TOP (to be Ordered Separately) SOIC SNAPHAT PACKAGE PROVIDES DIRECT CONNECTION FOR A SNAPHAT TOP WHICH CONTAINS THE BATTERY and CRYSTAL SOIC EMBEDDED CRYSTAL PACKAGE (MX) OPTION s s s s s s Figure 1. 28-pin SOIC Package SNAPHAT (SH) Battery & Crystal s s s 28 1 SOH28 (MH) s s Figure 2. 28-pin (300mil) SOIC Package EMBEDDED Crystal s s s s s SOX28 (MX) May 2003 Rev. 4.0 1/33 M41ST85Y, M41ST85W TABLE OF CONTENTS SUMMARY DESCRIPTION - - - - - - - - - - - . . . . 4 Figure 3. Logic Diagram - - - - - - - - - - - . . . 5 Table 1. Signal Names - - - - - - - - - - - . . . . 5 Figure 4. 28-pin SOIC Connections- - - - - - - -...