Premier Farnell
8bit 16k flash mcu, dip28, 168; series:atmega; memory size, flash:16kb; eeprom size:512byte; memory size, ram:1kb; i/o lines, no. of:35; adc inputs, no. of:6; timers, no. of:3; pwm channels, no of:6; frequency, clock:20mhz; interface type:i2c, spi, usart; voltage, supply min:2.7v; voltage, supply max:5.5v; termination type:through hole; case style:dip; pins, no. of:28; temperature, operating range:-40°c to +85°c; temp, op. max:85°c; temp, op. min:-40°c; base number:168; bits, no. of:8; ic generic number:168; interrupts, external no. of:26; logic function number:168; memory size:16 k; memory type:flash; microprocessor/controller features:high performance, low power avr® 8-bit microcontroller, advanced risc architecture, 4/8/16k bytes of in-system self-programmable flash, optional boot code section with independent lock bits, 256/512/512 bytes eeprom, 512/1k/1k byte internal sram; ram size:1024byte
http://grh.premierfarnell.com/grh.aspx?mid=1000082&sku=ATMEG... 
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