Microcontroller incorporating a 24-bit ΔΣ A/D converter for measuring instruments including smart meters
The RX21A group is the product that 24-bit Delta-sigma ADC is built in for measuring instruments such as a smart meter.
PGA (Programmable Gain Amp) is built in Delta-sigma ADC, which is possible to amplify analog signal at most 64 times.
The RX21A group has peripheral functions with special features, such as RTC which enables Time capture on event-signal input through external pins and DEU (Data Encryption Unit) which enables to use Encryption/decryption functions of the AES standard.
|CPU core||RX CPU General registers: 32-bit x 16
Multiplier: 32-bit multiplier Divider: Yes
Multiply-accumulator: Yes (two types: memory-to-memory operations and register-to-register operations)
Memory-protection unit (MPU)
|Maximum operating frequency||50 MHz|
|Power supply voltage||1.8 to 3.6 V|
|Program Flash||max. 512 KB|
|Data Flash||8 KB|
|SRAM||max. 64 KB|
|On-chip peripheral functions||Transfer functions||DMA controller (DMACA): 4 channels
Data transfer controller (DTCa)
|Timers||Multi-function timer pulse unit 2: 16 bits x 6 channels (MTU2a)
Port output enable 2 (POE2a)
8-bit timer (TMR): 8 bits x 2 channels x 2 units
Compare match timer (CMT): 16 bits x 2 channels x 2 units
Watchdog timer (WDTA): 14 bits
Realtime clock (RTCb)
|Communication functions||Serial communications interface (SCIc): 5 channels (1ch: IrDA x 1channel)
I2C bus interface (RIIC): 100, 80-pin:2 channels; 64-pin: 1 channel
Serial peripheral interface (RSPI): 2 channels
|Analog functions||24-bit Delta-sigma A/D converter (DSAD): 100-pin: 7 channels; 80-pin: 4 channels; 64-pin: 3 channels
10-bit A/D converter (AD): 100, 80-pin: 7 channels; 64-pin: 4 channels
10-bit D/A converter (DA): 100, 80-pin: 2 channels; 64-pin: none
ComparatorA (CMPA): 100, 80-pin: 2 channels;, 64-pin: 1 channel
ComparatorB (CMPB): 2 channels
|Encryption functions||Data Encryption Unit (DEU)|
|Safety functions||Clock Frequency Accuracy Measurement Circuit (CAC)
Data Operation Circuit (DOC)
Independent watchdog timer (IWDTa): 14 bits
Self-diagnosis Function of 10-bit ADC/AD Input Disconnection
Detection CRC Calculator (CRC)
|Clock Generation Circuit||Main clock oscillator
Low-speed on-chip oscillator (LOCO)
High-speed on-chip oscillator (HOCO)
PLL frequency synthesizer
Dedicated on-chip oscillator for the IWDT
|Others||Event link controller (ELC)
Multifunction Pin Controller (MPC)
Temperature Sensor (TEMPSa)
Power-on reset Circuit (POR)
Voltage Detection Circuit (LVD)
|On-chip debugging function||Planning|
|Low power consumption modes||4 modes
All-module clock stop mode
Software standby mode
Deep software standby mode
|Packages||PLQP0064KB-A (64-pin LFQFP,10x10mm,0.5mm pitch)
PLQP0080KB-A (80-pin LFQFP,12x12mm,0.5mm pitch)
PLQP0100KB-A (100-pin LFQFP,14x14mm,0.5mm pitch)
PTLG0100JA-A(100-pin TFLGA,7ｘ7mm,0.65mm pitch）
Pin Count / Memory Size Lineup:
Below you will find information to support the development of your application.
You can find an explanation of orderable part numbers here.
Resources for Software and Hardware
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|e-learning||Information for studying and learning about microcontrollers and microprocessors.|
|FAQ||Frequently asked questions and useful hints for development.|
|Forum||A forum and community site to share technical information, questions and opinions with others who use Renesas products.|
|Video||Watch videos related to this product.|
Software Design Support
|CS+||An integrated development environment that can be used for coding, assembling/compiling, and simulation. (Also included with Renesas Starter Kits.)|
|e2 studio||Renesas eclipse embedded studio, known as e² studio, is a complete development and debug environment based on the popular Eclipse CDT project.|
|E1||A standard Renesas on-chip debugging emulator that enables users to carry out ample debugging for real development at low cost. (Also included with starter kits.)|
Hardware Design Support
|IBIS/BSDL||IBIS standard simulation data is required for high-speed board design and can be used to run simulations to examine and troubleshoot issues such as waveform reflection, ringing, and so on, before producing the actual board.
BSDL is a data input format supported by most IEEE 1149.1 (JTAG)-compliant tools. The automatic test pattern generation (ATPG) and automatic test equipment functions of these tools facilitate testing.
Please search for your resonator on its manufacturer's site linked below. If you require optimal oscillation circuit constants for your particular system, please ask the manufacturer of the oscillator.
For Main clock resonator :
Murata Manufacturing: For IC Manufacturer, select Renesas Electronics, and enter R5F521A into the IC Part Number search box.
For Sub clock resonator :
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