MK41T56

MK41T56 MKI41T56 512 bit (64b x8) Serial Access TIMEKEEPER® SRAM COUNTERS for SECONDS, MINUTES, HOURS, DAY, DATE, MONTH and YEARS SOFTWARE CLOCK CALIBRATION AUTOMATIC POWER-FAIL DETECT and SWITCH CIRCUITRY I2C BUS COMPATIBLE 56 BYTES of GENERAL PURPOSE RAM ULTRA-LOW BATTERY SUPPLY CURRENT of 500nA OPERATING TEMPERATURE: – MK41T56: 0 to 70°C – MKI41T56: –40 to 85°C AUTOMATIC LEAP YEAR COMPENSATION DESCRIPTION The MK41T56 TIMEKEEPER® is a low power 512 bit static CMOS RAM organized as 64 words by 8 bits. A built-in 32.768 kHz oscillator (external crystal controlled) and the first 8 bytes of the RAM are used for the clock/calendar function and are configured in binary coded decimal (BCD) format. Addresses and data are transferred serially via a two-line bi-directional bus. The built-in address register is incremented automatically after each write or read data byte. The MK41T56 clock has a built-in power sense circuit which detects power failures and automatically switches to the battery supply during power failures. The energy needed to sustain the RAM and clock operations can be supplied from a small lithium button cell. Table 1. Signal Names OSCI OCSO FT/OUT SDA SCL VBAT VCC VSS March 1999 Oscillator Input Oscillator Output Frequency Test / Output Driver (Open Drain) Serial Data Address Input / Output Serial Clock Battery Supply Voltage Supply Voltage Ground 1/15 8 1 PSDIP8 (N) 0.4mm Frame 8 1 SO8 (S) 150mil Width Figure 1. Logic Diagram VCC VBAT OSCI SCL MK41T56 MKI41T...