MRF21010

The MRF21010 has an 8-channel PDC dedicated to the three on-chip USARTs and to the SPI. One PDC channel is connected to the receiving channel and one to the transmitting channel of each peripheral. The user interface of a PDC channel is integrated in the memory space of each USART channel and in the memory space of the SPI. It contains a 32-bit address pointer register and a 16-bit count register. When the programmed data is transferred, an end-of-transfer interrupt is generated by the corresponding peripheral. See the USART section and the SPI section for more details on PDC operation and programming.

The MRF21010 is designed to appear to the systems designer as a microprocessor peripheral, and will easily interface with popular single-chip micro- processors (80C51 typical) for control of modem functions through its 8-bit multiplexed address/data bus or via an optional serial control bus. An ALE control simplifies address demultiplexing. Data communications normally occur through a separate serial port.During turn-off of the lower MOSFET, the LGATE voltage is monitored until it reaches a 1.0V threshold, at which time the UGATE is released to rise. Adaptive shoot-through circuitry monitors the PHASE voltage during UGATE turn-off. Once PHASE has dropped below a threshold of 0.5V, the LGATE is allowed to rise. PHASE continues to be monitored during the lower gate rise time. If the PHASE voltage exceeds the 0.5V threshold during this period and remains high for longer than 2µs, the LGATE transitions low. Both upper and lower gates are then held low until the next rising edge of the PWM signal.

The contents of the offset registers MRF21010 can be read to the data outputs when WEN2/LD is LOW and both REN1 and REN2 are LOW. LOW-to-HIGH transitions of RCLK read register contents to the data outputs. Writes and reads should not be performed simultaneously on the offset registers.ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although this product features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.