Overview
The ATmega48/88/168 is a low-power CMOS 8-bit microcontroller based on the AVR
enhanced RISC architecture. By executing powerful instructions in a single clock cycle, the ATmega48/88/168 achieves throughputs approaching 1 MIPS per MHz allowing the system designer to optimize power consumption versus processing speed.

FEATUREs
• High Performance, Low Power AVR® 8-Bit Microcontroller
• Advanced RISC Architecture
   – 131 Powerful Instructions – Most Single Clock Cycle Execution
   – 32 x 8 General Purpose Working Registers
   – Fully Static Operation
   – Up to 20 MIPS Throughput at 20 MHz
   – On-chip 2-cycle Multiplier
• Non-volatile Program and Data Memories
   – 4/8/16K Bytes of In-System Self-Programmable Flash (ATmega48/88/168)
      Endurance: 10,000 Write/Erase Cycles
   – Optional Boot Code Section with Independent Lock Bits
      In-System Programming by On-chip Boot Program
      True Read-While-Write Operation
   – 256/512/512 Bytes EEPROM (ATmega48/88/168)
      Endurance: 100,000 Write/Erase Cycles
   – 512/1K/1K Byte Internal SRAM (ATmega48/88/168)
   – Programming Lock for Software Security
• Peripheral Features
   – Two 8-bit Timer/Counters with Separate Prescaler and Compare Mode
   – One 16-bit Timer/Counter with Separate Prescaler, Compare Mode, and Capture
      Mode
   – Real Time Counter with Separate Oscillator
   – Six PWM Channels
   – 8-channel 10-bit ADC in TQFP and MLF package
   – 6-channel 10-bit ADC in PDIP Package
   – Programmable Serial USART
   – Master/Slave SPI Serial Interface
   – Byte-oriented 2-wire Serial Interface
   – Programmable Watchdog Timer with Separate On-chip Oscillator
   – On-chip Analog Comparator
   – Interrupt and Wake-up on Pin Change
• Special Microcontroller Features
   – Power-on Reset and Programmable Brown-out Detection
   – Internal Calibrated Oscillator
   – External and Internal Interrupt Sources
   – Five Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, and
      Standby
• I/O and Packages
   – 23 Programmable I/O Lines
   – 28-pin PDIP, 32-lead TQFP and 32-pad MLF
• Operating Voltage:
   – 1.8 - 5.5V for ATmega48V/88V/168V
   – 2.7 - 5.5V for ATmega48/88/168
• Temperature Range:
   – -40°C to 85°C
• Speed Grade:
   – ATmega48V/88V/168V: 0 - 4 MHz @ 1.8 - 5.5V, 0 - 10 MHz @ 2.7 - 5.5V
   – ATmega48/88/168: 0 - 10 MHz @ 2.7 - 5.5V, 0 - 20 MHz @ 4.5 - 5.5V
• Low Power Consumption
   – Active Mode:
      1 MHz, 1.8V: 240µA
      32 kHz, 1.8V: 15µA (including Oscillator)
   – Power-down Mode:
      0.1µA at 1.8V