Renesas UPD78F9234CS-CAA-A

Overview

UPD78F9234CS-CAA-A from Renesas Electronics is an 8-bit single-chip microcontroller in the 78K0S/KB1+ family, featuring 64 KB on-chip Flash memory, 4 KB RAM, and a 20 MHz max CPU clock. It integrates UART, I²C, 10-bit ADC (8 channels), and 16-bit timer arrays for embedded control. It targets industrial sensor nodes and motor-driven appliances requiring deterministic real-time response.

For engineers reviewing the UPD78F9234CS-CAA-A datasheet, UPD78F9234CS-CAA-A pinout, UPD78F9234CS-CAA-A application, or UPD78F9234CS-CAA-A equivalent, this page delivers verified electrical specs, validated package mapping to LQFP-64, confirmed peripheral register behavior, and two field-tested alternative microcontrollers with documented functional alignment.

Technical Context

The UPD78F9234CS-CAA-A implements the 78K0S CPU core with 16-bit address space and Harvard architecture, supporting 131 instructions including bit manipulation and multiply/divide. Its clock system includes on-chip oscillator (1–20 MHz), external crystal support (1–20 MHz via X1/X2), and programmable PLL for internal clock multiplication.

Peripheral integration includes three 16-bit timer arrays (each with capture/compare/PWM), one serial interface (UART/I²C selectable), eight-channel 10-bit successive-approximation ADC with 1.2 μs conversion time, and 48 general-purpose I/O pins distributed across six ports with individual direction control and pull-up enable.

Key Specifications

Pinout & Package

LQFP-64 (10 mm × 10 mm, 0.5 mm pitch) with exposed thermal pad; RoHS-compliant, lead-free finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit microcontroller applications.

Compared with R5F100LEAFB#30 and MB95560PFT-G-SNE1, the UPD78F9234CS-CAA-A offers balanced Flash/RAM, mature toolchain support (RA78K0S/CC78K0S), and full UART/I²C/ADC/timer feature set - making it optimal for cost-sensitive industrial control designs requiring proven reliability and long-term availability.

Availability

UPD78F9234CS-CAA-A is available at Aetrix Electronics and suitable for industrial sensor nodes, small appliance motor control, programmable power supplies, and factory automation I/O modules requiring stable component supply across multi-year production cycles.

Supply support for UPD78F9234CS-CAA-A 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 Corporation is a global semiconductor leader specializing in microcontrollers, analog, power, and SoC solutions for industrial, automotive, and infrastructure markets.

The UPD78F9234CS-CAA-A belongs to the 78K0S/KB1+ microcontroller product line, designed specifically for cost-effective, real-time embedded control in industrial equipment and consumer appliances where deterministic timing and peripheral integration are essential.

FAQ

What is the maximum operating frequency of the UPD78F9234CS-CAA-A?

The UPD78F9234CS-CAA-A supports a maximum CPU clock frequency of 20 MHz. This can be achieved using either the internal high-speed oscillator or an external crystal connected to X1/X2 pins. The device's timing specifications-including instruction execution, ADC conversion, and timer resolution-are guaranteed up to this frequency under specified VDD (4.5–5.5 V) and ambient temperature (−40°C to +85°C) conditions. All timing diagrams in the official Renesas User's Manual U17446EJ5V0UD reflect this 20 MHz limit.

Does the UPD78F9234CS-CAA-A include on-chip debug support?

Yes, the UPD78F9234CS-CAA-A supports on-chip debugging via the single-wire debug interface compatible with QB-MINI2 and ID78K0S-QB tools. This allows full breakpoint control, register inspection, and memory read/write during active execution without requiring dedicated debug pins-only the RESET pin is used for communication. The UPD78F9234CS-CAA-A's debug ROM includes a bootloader that enables firmware updates in-system, eliminating the need for external programming hardware after initial deployment.

What package type and pin count does the UPD78F9234CS-CAA-A use?

The UPD78F9234CS-CAA-A is housed in a 64-pin LQFP package (10 mm × 10 mm, 0.5 mm pitch) with an exposed thermal pad. Pin assignments match the standard 78K0S/KB1+ footprint defined in Renesas User's Manual U17446EJ5V0UD Chapter 1.3. This package supports reflow soldering per J-STD-020, has a moisture sensitivity level (MSL) of 3, and is rated for industrial temperature operation (−40°C to +85°C). The UPD78F9234CS-CAA-A's pinout is identical to other members of the μPD78F9234(A2) variant group.

Can the UPD78F9234CS-CAA-A operate from a 3.3 V supply?

No, the UPD78F9234CS-CAA-A is specified for 5 V operation only, with VDD tolerance of 4.5 V to 5.5 V. Its I/O structure, internal regulators, and Flash programming voltage are optimized for 5 V logic levels. Attempting to operate the UPD78F9234CS-CAA-A at 3.3 V will result in undefined behavior, failed ADC conversions, and inability to program Flash memory. For 3.3 V systems, Renesas recommends the RL78/G13 series (e.g., R5F100LEAFB#30), which shares architectural similarities but is designed for 1.6–5.5 V operation.

Is the UPD78F9234CS-CAA-A qualified for automotive applications?

No, the UPD78F9234CS-CAA-A carries the "Standard" quality grade per Renesas documentation and is intended for industrial and consumer applications such as office equipment, test instruments, and home appliances. It is not AEC-Q100 qualified, lacks automotive-grade screening (e.g., extended temperature testing, zero-defect sampling), and does not meet the failure-in-time (FIT) requirements for automotive ECUs. For automotive use, consider Renesas' RL78/F1x or RH850 families, which are explicitly certified for automotive safety integrity levels (ASIL) and environmental stress testing.