Renesas R5F11778GNA#20

Overview

R5F11778GNA#20 from Renesas Electronics is an ultra-low-power 16-bit RL78/I1D microcontroller in a 24-pin HWQFN (4 × 4 mm, 0.5 mm pitch) package, featuring 8 KB flash memory, 2 KB data flash, 0.7 KB RAM, 18 I/O pins, and industrial-grade operation from −40°C to +105°C. It integrates dual serial interfaces (2× CSI, 1× UART, 2× simplified I²C), 4-channel 16-bit timers, RTC with calendar, 6-channel 8/12-bit ADC, 2 comparators, and 4 operational amplifiers - optimized for battery-powered sensor nodes and industrial control modules.

For engineers reviewing the R5F11778GNA#20 datasheet, R5F11778GNA#20 pinout, R5F11778GNA#20 application, or R5F11778GNA#20 equivalent, this page delivers verified technical context, validated pin functions, real-world use cases, and confirmed alternative options - all grounded in Renesas' official R01DS0244EJ0241 Rev. 2.41 datasheet and ordering documentation.

Technical Context

The R5F11778GNA#20 implements the RL78 CPU core with CISC architecture, 3-stage pipeline, and selectable instruction execution time (0.04167 μs at 24 MHz high-speed on-chip oscillator or 66.6 μs at 15 kHz low-speed mode). It supports true low-power operation: 58.3 μA/MHz active current and 0.64 μA in STOP mode with RTC2 and LVD active.

Its clock system includes high-speed (1–24 MHz), middle-speed (1–4 MHz), and low-speed (15 kHz) on-chip oscillators, plus external crystal support (X1 up to 20 MHz, XT1 at 32.768 kHz). Peripheral integration centers on event-driven operation via the Event Link Controller (ELC) with 20 event inputs and 5 trigger outputs, and DMA-like data transfer via the Data Transfer Controller (DTC) with 20 activation sources.

Key Specifications

Pinout & Package

Package: 24-pin HWQFN (4 × 4 mm, 0.5 mm pitch), exposed die pad recommended to be connected to VSS. Pinout conforms to Renesas' official top-view layout for 24-pin RL78/I1D devices (R01DS0244EJ0241, p.7).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microcontroller applications.

Compared with R5F11778GNA#20, R5F1177AGNA#20 offers scalable memory headroom within identical packaging and pinout, while R5F11768GSP#30 trades I/O count and package thermal performance for board area reduction - enabling tiered design reuse across product variants.

Availability

R5F11778GNA#20 is available at Aetrix Electronics and suitable for industrial sensor nodes, smart utility meters, PLC I/O modules, and factory automation edge controllers requiring stable component supply, long-term lifecycle assurance, and guaranteed industrial-temperature operation.

Supply support for R5F11778GNA#20 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Renesas Electronics is a global semiconductor leader delivering microcontrollers, analog, power, and SoC solutions for automotive, industrial, infrastructure, and IoT markets.

The RL78/I1D family - including R5F11778GNA#20 - is engineered for ultra-low-power general-purpose embedded control, targeting battery-operated industrial equipment, energy metering, and sensor-edge applications demanding robustness across −40°C to +105°C.

FAQ

What is the maximum operating frequency and instruction execution time of the R5F11778GNA#20?

The R5F11778GNA#20 supports a maximum high-speed on-chip oscillator frequency of 24 MHz, yielding a minimum instruction execution time of 0.04167 μs. It also supports lower-frequency modes down to 15 kHz (66.6 μs execution time) for ultra-low-power operation. The actual frequency depends on option byte and HOCODIV register settings, and is validated across 1.6–3.6 V supply and −40°C to +105°C temperature range per R01DS0244EJ0241.

Does the R5F11778GNA#20 support hardware debugging, and what are the constraints?

Yes, the R5F11778GNA#20 includes an on-chip debug function accessible via TOOL0 (P40) and TOOLRxD/TOOLTxD (P55/P54). However, Renesas explicitly cautions against using this feature in mass-produced products due to potential flash memory wear-out beyond guaranteed rewrite cycles. For production units, debug should be limited to development; final firmware must be programmed via non-debug methods to ensure reliability.

How many serial communication interfaces does the R5F11778GNA#20 provide, and what types are supported?

The R5F11778GNA#20 provides two Simplified SPI (CSI) channels, one UART channel, and two simplified I²C channels - totaling five serial interfaces. This configuration is confirmed for 24-pin RL78/I1D variants (R5F1177x) in Section 1.6 of R01DS0244EJ0241. All interfaces support interrupt-driven operation and can be linked via the Event Link Controller (ELC) for autonomous peripheral coordination.

What analog peripherals are integrated into the R5F11778GNA#20, and how are they configured?

The R5F11778GNA#20 integrates a 6-channel 8/12-bit A/D converter with internal 1.45 V reference and temperature sensor, two comparators (IVCMP0/IVCMP1), and four operational amplifiers (AMP0–AMP3). Pins P12–P14, P20–P22, and P30–P31 serve dual analog/digital roles. Op-amp inputs (e.g., AMP0+ on P12, AMP0− on P13) and outputs (e.g., AMP0O on P14) are fixed per pin mapping - no software remapping - ensuring predictable signal chain layout.

Is the R5F11778GNA#20 pin-compatible with other RL78/I1D variants in the same package?

Yes, the R5F11778GNA#20 shares identical 24-pin HWQFN pinout and electrical characteristics with other GNA-packaged RL78/I1D parts (e.g., R5F1177AGNA#20, R5F11778GNA#U0). All share the same pin configuration, register map, and peripheral assignment per R01DS0244EJ0241 Figure 1-3. Memory differences (8 KB vs. 16 KB flash) do not affect pin behavior or compatibility - enabling drop-in firmware upgrades within the same package family.