AVR® microcontrollers combining USB controller and high performance analog features. The ATmega16U4 and ATmega32U4 reduce system cost in battery powered devices such as gaming accessories.
Battery powered devices can take advantage of being connected to a USB port to recharge. However, modern batteries require sophisticated algorithms to accelerate and optimize charging, while USB brings further constraints on the battery charging since it is limited both in the voltage and the maximum current it can provide. The new AVR devices allow optimized battery charging combined with USB functions. The analog to digital converter can be used to sense motion or pressure in the end application and the high-speed PWM is ideal for low cost motor control.
Gaming peripherals, such as sophisticated joysticks also require a number of analog to digital conversion channels and several PWM channels to drive force-feedback motors. The new devices have a rich feature set that address those needs and optimize the global system cost. This includes a 10-bit ADC with 12 channels; a built-in temperature sensor allowing compensating thermal effects on analog performance; a programmable gain x1, x10, x40 and x200 giving more flexibility to measure differential voltages for current monitoring. A high-speed timer with three PWM channels with complementary outputs and programmable dead-times allows 8-bit resolution PWM with an industry-best frequency of 500 kHz, up to 11-bit resolution PWM with a frequency over 60 kHz.
A hardware flow control on the USART eases the connection to other devices when bridging with USB at high baud rates. Digital inputs with TTL thresholds ease interface with 3V devices in mixed 5/3V applications. A On-Chip 3.3V regulator can deliver up to 50 mA and supply external devices in USB powered applications. Jitter and accuracy of the On-Chip 8 MHz calibrated RC oscillator can support serial communication without crystal. All devices include a hardware multiplier, one USART, one SPI, one TWI, two 8-bit and two 16-bit timers with PWM and 26 programmable I/Os.
