See Littelfuse Commercial Vehicle Products Products
Real Time Clock Serial - 64byte Clock/Calendar/Alarm/Battery Backup Automotive 8-Pin MSOP - Tube
Battery-Backed I2C Real-Time Clock/Calendar - 64-byte SRAM - 1.8 to 5.5VDC - 12/24 hour - I2C - -40°C to +85°C - ...
I2C-BUS INTERFACE RTC 5+/-23PPM (VSOJ-20) 250TR
Real Time Clock Serial - 64byte Clock/Calendar/Alarm Automotive 8-Pin PDIP - Tube
RX4901CE XB C06 REAL TIME CLOCK 4 WIRE SPI-BUS +/-5PPM -40~85C PIN 4FOUT 2K TR
RX-8571LC:B3PURESN
RX4901CE XS D00 REAL TIME CLOCK 4 WIRE SPI-BUS +/-3PPM -40~85C PIN 4EVIN3 1K TR
RX-4035SA:AA0 PURE SN REAL TIME CLOCK 5+/-5PPM 1K T/R
RX-8025NB:AC3 PURE SN REAL TIME CLOCK 0+/-5PPM 250 T/R