R5F211B4SP#W4 - 16KB Flash 16-Bit R8C MCU | Renesas | 20MHz
MPN: R5F211B4SP#W4 ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.74 | $4.74 |
| 10 | $4.27 | $42.70 |
| 100 | $3.79 | $379.00 |
| 500 | $3.41 | $1,705.00 |
| 1,000 | $3.04 | $3,040.00 |
R5F211B4SP#W4 Overview
What is an R8C microcontroller? The R8C is a family of 16-bit CISC microcontrollers from Renesas built around the R8C/Tiny CPU core, occupying a middle ground between 8-bit MCUs (such as the 78K0 or PIC16) and 32-bit devices. R8C parts share a common instruction set with the higher-end M16C family, support up to 16-bit internal data paths, and feature a compact instruction set that delivers high code density. They are widely used in consumer appliances, sensor-conditioning nodes, motor sub-controls, and human-interface subsystems where deterministic interrupt response and small footprint are required.
Key features include 16 KB on-chip flash, 1024 bytes of RAM, 4096 bytes of data flash for non-volatile parameter storage, 12 on-chip I/O pins (shared with peripherals), one 16-bit timer, multiple 8-bit timers, a 10-bit A/D converter, UART and I2C serial interfaces, and a watchdog timer. The R8C/1B group also offers low-power modes including Halt, Stop, and Wait, along with voltage-detector reset and clock-prescaler options for power-conscious designs.
The device is implemented in CMOS with a built-in oscillator (no external crystal required in many applications) and supports on-chip debug via a single-wire interface. Operating voltage is 3.0 V to 5.5 V and the operating temperature range covers -20 °C to +85 °C for the standard commercial grade.
Typical applications include small appliance control, IR remote receivers, sensor signal-conditioning front ends, battery chargers, LED lighting controllers, and consumer human-interface devices. The 20-pin LSSOP footprint and minimal external BOM make it attractive as a drop-in upgrade for older 8-bit designs that need 16-bit arithmetic headroom.
When designing with this part, place decoupling capacitors within 5 mm of VCC/AVCC and provide a solid ground pour under the device. For applications needing higher noise immunity or CAN connectivity, consider the larger R8C/2x or RL78/G12 families that Renesas recommends for new designs.
This page consolidates distributor stock data, parametric compatibility notes, and cross-reference alternatives for the R5F211B4SP#W4 — information not aggregated in the bare manufacturer datasheet.
Drop-in alternatives for R5F211B4SP#W4 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with R5F211B4SP#W4 (same form factor and footprint) — differing in A/D Converter, Package, Core Architecture, Operating Temperature, Supply Voltage Range.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
R5F211B4DSP#W4
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
R5F211B4NP#U0
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
R5F211A4SP#W4
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
R5F211B4SP#W4 Maximum Ratings & Electrical Characteristics
| Core | R8C/Tiny Series |
| Data Bus Width | 16-bit |
| Maximum Clock Frequency | 20 MHz |
| Program Memory Size | 16 KB (16K x 8) Flash |
| RAM Size | 1 KB |
| Data Flash | 4 KB |
| Supply Voltage | 3.0 V to 5.5 V |
| Operating Temperature | -20 °C to +85 °C |
| Package | 20-LSSOP |
| Mounting Type | Surface Mount |
| Number of I/O Pins | 12 |
| A/D Converter | 10-bit |
| Timers | 16-bit x 1, 8-bit x multiple |
| Communication Interfaces | UART, I2C |
| Watchdog Timer | Yes |
| On-chip Debug | Single-wire |
| Lead Free / RoHS | Pb-Free, RoHS compliant |
| Packaging Form | Tape & Reel (W4) |
R5F211B4SP#W4 Pin Configuration
| Pin 1 | MODE — Operating mode select (single-chip mode at high) |
| Pin 2 | RESET — Reset input (active low) |
| Pin 3 | XIN — External clock input |
| Pin 4 | XOUT — External clock output |
| Pin 5 | VREF — A/D converter reference voltage |
| Pin 6 | AVSS — Analog ground |
| Pin 7 | P1_0/AN0 — Port 1 bit 0 / A/D input 0 |
| Pin 8 | P1_1/AN1 — Port 1 bit 1 / A/D input 1 |
| Pin 9 | P1_2/AN2 — Port 1 bit 2 / A/D input 2 |
| Pin 10 | P1_3/AN3 — Port 1 bit 3 / A/D input 3 |
| Pin 11 | P4_3 — Port 4 bit 3 |
| Pin 12 | P4_2 — Port 4 bit 2 |
| Pin 13 | P3_4 — Port 3 bit 4 |
| Pin 14 | P3_5 — Port 3 bit 5 |
| Pin 15 | P3_6 — Port 3 bit 6 |
| Pin 16 | P3_7 — Port 3 bit 7 |
| Pin 17 | P4_0 — Port 4 bit 0 |
| Pin 18 | P4_1 — Port 4 bit 1 |
| Pin 19 | VCC — Supply voltage (3.0 V to 5.5 V) |
| Pin 20 | VSS — Ground |
Typical Applications
R5F211B4SP#W4 is suitable for 6 applications: Small Appliance Control, IR Remote Receiver Decoder, Battery Charger Controller, LED Lighting Controller, Sensor Signal Conditioning Front End, Consumer Human-Interface Device.
Small Appliance Control
The R5F211B4SP#W4 fits small-appliance control boards because it integrates 16 KB of flash, 12 GPIO, a 10-bit A/D for thermistor or current sensing, and a 16-bit timer for triac phase control, all in a compact 20-pin LSSOP. With 3.0 V to 5.5 V operation, it interfaces directly to 5 V relay drivers and zero-cross detectors, eliminating the need for level shifters. The R8C/Tiny core's CISC instruction set produces dense code, often allowing the entire application to fit within 16 KB. Designers commonly use it in coffee makers, blenders, and rice cookers where low BOM cost and proven reliability are priorities.
Recommended
IR Remote Receiver Decoder
The R5F211B4SP#W4 is well-suited as an IR remote receiver decoder because its 16-bit timer can capture the 38 kHz carrier pulse widths with sub-microsecond resolution and the 10-bit A/D is unnecessary for pure digital demodulation. Operating from 3 V to 5 V, it powers directly from two AA cells or a USB-derived 3.3 V rail. The R8C/Tiny core's fast interrupt response keeps up with NEC, RC5, and Sony SIRC protocols without dropping frames. Low-power Halt and Stop modes let the device draw microamps in standby, which is critical for battery-powered handsets.
Recommended
Battery Charger Controller
The R5F211B4SP#W4's 10-bit A/D converter monitors charge voltage and current with adequate resolution for CC/CV lithium-ion charge profiles, while its 16-bit timer drives PWM into a power MOSFET. The 4 KB data flash conveniently stores calibration tables and learned battery capacity. Wide 3.0 V to 5.5 V supply tolerance tolerates wall-adapter ripple, and the on-chip voltage detector provides a clean power-on reset without external components. Designers can implement USB-C PD or legacy 5 V charger topologies around this MCU while keeping the bill of materials small.
Recommended
LED Lighting Controller
For LED lighting controllers, the R5F211B4SP#W4's 16-bit timer generates high-resolution PWM dimming without flicker, and the 10-bit A/D reads ambient-light sensors and thermistors for closed-loop brightness and thermal foldback. Operating from 3.3 V or 5 V, it works alongside standard constant-current LED drivers. The R8C/Tiny's deterministic interrupt latency ensures zero visible PWM jitter at 1 kHz refresh rates, which is critical for premium lighting applications. Small 20-pin LSSOP package fits into space-constrained bulb and strip form factors.
Recommended
Sensor Signal Conditioning Front End
The R5F211B4SP#W4 functions as a sensor front-end MCU because its 10-bit A/D digitizes thermistor, photodiode, or strain-gauge signals, while 4 KB of data flash stores per-unit calibration. UART or I2C then forwards processed readings to a host processor or display. The MCU's wide supply range lets it share the same 3.3 V or 5 V rail as analog signal-chain components, simplifying power-tree design. The single-wire on-chip debug interface accelerates firmware iteration during sensor characterization and factory tuning.
Recommended
Consumer Human-Interface Device
The R5F211B4SP#W4 drives human-interface subsystems like button matrices, rotary encoders, and small LCDs because its 12 GPIO pins handle multiple inputs and outputs, while UART provides communication with a host SoC. The R8C/Tiny core responds to button interrupts within a few microseconds, producing lag-free user experiences. Built-in watchdog and voltage-detector features protect against firmware lockups during unattended operation, making the part suitable for kitchen, hobby, and personal-care appliances.
Recommended
Recommended Products Summary
Engineering reference data for R5F211B4SP#W4 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | R5F211B4DSP#W4 | R5F211B4NP#U0 | R5F211A4SP#W4 |
|---|---|---|---|---|
| Package | 20-LSSOP | 20-LSSOP - same | 20-LSSOP - same | 20-LSSOP - same |
| Brand | Renesas Electronics | Renesas Electronics | Renesas Electronics | Renesas Electronics |
| Core Architecture | R8C/Tiny 16-bit CISC | R8C/Tiny 16-bit CISC - same | R8C/Tiny 16-bit CISC - same | R8C/Tiny 16-bit CISC - same (R8C/1A group) |
| Maximum Clock Frequency | 20 MHz | 20 MHz - same | 20 MHz - same | 20 MHz - same |
| Flash Memory | 16 KB | 16 KB - same | 16 KB - same | 16 KB - same |
| RAM | 1 KB | 1 KB - same | 1 KB - same | 1 KB - same |
| Operating Temperature | -20 °C to +85 °C | -40 °C to +85 °C (industrial) | -20 °C to +85 °C - same | -20 °C to +85 °C - same |
| Lifecycle Status | NRND | NRND | NRND | NRND |
Key Differentiators
- Industrial temperature range variant available (vs R5F211B4DSP#W4)
- Sustained product availability despite NRND status (vs R5F211B4NP#U0)
- R8C/1B group adds improved timers and peripheral set (vs R5F211A4SP#W4)
Design Notes
Place a 0.1 µF ceramic decoupling capacitor within 5 mm of the VCC pin (pin 19) and a bulk 10 µF electrolytic or tantalum on the supply rail. The R5F211B4SP#W4's internal voltage detector issues a clean power-on reset if VCC rise time stays below the datasheet specification; an external RC delay is otherwise needed. For analog accuracy, also decouple AVREF separately if the 10-bit A/D is in active use.
Route a continuous ground pour under the LSSOP-20 footprint and stitch vias around the perimeter to minimize digital return-current loops. Keep the XIN/XOUT traces short and symmetric, and guard them with a ground trace on either side to prevent noise coupling into the on-chip oscillator. If the on-chip debug pin is not connected at the board level, leave it accessible for in-system programming during prototyping.
When migrating from R8C/1A firmware to R8C/1B, double-check timer-channel assignments and A/D input mappings; some peripheral registers shifted between revisions. Always set the MODE pin high at power-up to ensure single-chip mode rather than boot mode. Use the watchdog timer to recover from unexpected firmware lockups in unattended appliance designs, and disable unused peripherals to lower quiescent current in battery-powered applications.
Compliance Information
Pb-Free and RoHS compliant per Renesas product page and DigiKey catalog. Not AEC-Q100 qualified - this is a general-purpose commercial MCU.
