ATmega4HVD/8HVD is a high performance, low power AVR® 8-bit microcontroller from Microchip. Its main features include: Advanced RISC architecture, 124 powerful instructions - most single clock cycle execution; 32 x 8 general purpose working registers; fully static operation; up to 4 MIPS throughput at 4 MHz; 4K/8K bytes of In-System Self-Programmable Flash (ATmega4HVD/8HVD); 256 Bytes EEPROM; 512 Bytes Internal SRAM; Write/Erase Cycles: 10,000 Flash/ 100,000 EEPROM; Data Retention: 20 years at 85°C /100 years at 25°C(1) - Programming Lock for Software Security.
This handbook describes the ATmega8HVD high‑voltage AVR microcontroller, covering its key features such as low‑power operation, battery‑management functions, and on‑chip peripherals. It includes pin‑out diagrams, detailed pin descriptions, and an overview of the device’s monitoring and protection circuitry for single‑cell Li‑ion applications.
The document also explains the AVR CPU core architecture, the ALU, status register, debugWIRE debugging interface, and self‑programming flash procedures. Electrical characteristics, memory programming methods, and ordering information are provided for designers and developers.
| Operating Voltage (VFET) | 2.1 V – 6.0 V |
|---|---|
| Operating Voltage (Voc) | 2.0 V – 2.4 V |
| Maximum Withstand Voltage (VFET) | 12 V |
| Maximum Withstand Voltage (High‑voltage pins) | 5 V |
| Temperature Range | -20 °C to 85 °C |
| Speed Grade | 1 MHz – 4 MHz |
| Flash Memory | 4 KB / 8 KB In‑System Self‑Programmable |
| EEPROM | 256 Bytes |
| SRAM | 512 Bytes |
| ADC | 10‑bit |
| General Purpose Working Registers | 32 × 8‑bit |
The VFET pin operates from 2.1 V to 6.0 V.
It provides 32 eight‑bit general‑purpose working registers.
The microcontroller includes the debugWIRE on‑chip debug system.
The device contains 256 bytes of EEPROM.