New AVR microcontrollers from Soanar
Atmel has announced new AVR microcontrollers combining USB controller and high performance analog features which are available from Soanar . 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 optimise 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 optimised 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 suitable 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 good feature set that address those needs and optimise the global system cost.
This includes a 10-bit ADC with 12 channels; a built-in temperature sensor; a programmable gain for 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 frequency of 500kHz, up to 11-bit resolution PWM with a frequency over 60kHz.
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 50mA and supply external devices in USB powered applications. Jitter and accuracy of the On-Chip 8MHz 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.
ATmega16U4 features 16 Kbytes of In-System Programmable (ISP) Flash, 1 Kbytes of RAM and 512 bytes of EEPROM. ATmega32U4 features 32 Kbytes of In-System Programmable (ISP) Flash, 2.5 Kbytes of RAM and 1 Kbytes of EEPROM. They are available in 44-pin packages.
An extensive software library is offered to support the most-relevant USB classes for the embedded market: Mass Storage Device (MSD), Human Interface Device (HID), Device Firmware Upgrade (DFU), Communication Device Class (CDC), Audio Class, etc. Examples of composite devices actually combine several classes in one device, for instance audio and HID can be combined to make a headset with remote control, toys, etc.
The parts are supported by the new release of AVR Studio which is available from the Atmel website. Both JTAGICE MkII and AVR Dragon are supported tools.
The STK600-TQFP44 includes a dedicated adapter board so these specific devices can connect on the generic STK600 Starter Kit. This will soon be complemented by the EVK527 a standalone evaluation kit allowing the evaluation of HID, mass storage, audio and battery charging applications.
28-Mar-2008