Renesas Technology America has added 36 16-bit microcontrollers to its R8C/Tiny product line, bringing to 72 the number of devices available for in-vehicle body-control applications.
MCUs in the 80-pin R8C/38E, 64-pin R8C/36E, and 48-pin R8C/34E product groups have on-chip flash memory and a built-in precision clock oscillator. Models are available with 32 KB, 48 KB and 64 KB of flash ROM are available, accompanied by 2.5 KB, 4 KB and 6 KB of flash RAM respectively. The MCUs can be shipped with blank flash, or pre-programmed with customer-supplied user code.
Some models also include 4 KB of on-chip data storage flash memory, some include a CAN controller interface, and some are available in packages with extra I/O pins. The MCUs are available in standard (-40 to +85 °C) and extended (-40 to +125 °C) operating temperature ranges.
Renesas said the expanded R8C/Tiny product line, which also includes 20-pin and 32-pin packages, makes it easier for automotive engineers to find the best MCU solution for a particular application development and fine-tuning. By switching from one device in the family to another, developers can add functions or increase memory capacity.
The new MCUs also offer improvements in various on-chip peripheral functions. The on-chip oscillator, for example, delivers ±1% precision, eliminating the need for an external resistor to implement the clock circuit.
The data flash built into some R8C/Tiny models eliminates the need for external EEPROM (electrically erasable and programmable read only memory) for data storage. A background-operation (BGO) function allows the CPU to execute instructions during data flash reading or writing, boosting the MCU’s processing efficiency and allowing system engineers to write programs without concern for data flash read/write times. The data flash capacity has been doubled to a total of 4 KB (1 KB × 4 blocks) over that of previous products.
Renesas has also expanded the number and capabilities of the on-chip voltage-detection circuits. Previous R8C/Tiny devices had two circuits that detected one level each, while the new MCUs have three circuits that respectively offer one detection level, eight detection levels, and two detection levels, with external input capability.
A data transfer controller (DTC) enables data transfers to be performed between memory and a register without CPU intervention, thus shortening transfer-processing time and reducing the load on the CPU to make more computing time available for executing application code. The DTC is based on the design used in the 16-bit H8S and 32-bit H8SX series.
The new MCUs incorporate a new power-on reset (POR) function that places all on-chip circuits in the reset state when the MCU is turned on. The POR circuit can now handle a slower power supply voltage ramp-up.
A single-pin debugging interface that lets system engineers use the Renesas E8a emulator/on-chip debugger as a development environment even while all I/O pins are in use. An additional debugging function allows developers to make RAM references and changes during user program execution. The E8a emulator can be used as a code writer for the MCU’s on-chip flash memory. Renesas plans to offer support for the E100 full-spec emulator for situations requiring a more powerful debugging tool.
Prices range from $3.50 to $6.40 for standard operating temperature devices.