Renesas M38C37ECMFS

Overview

M38C37ECMFS from Renesas Electronics is an 8-bit CMOS single-chip microcomputer in the 38C3 Group (740 Family), featuring on-chip mask ROM, 16-bit timer A with PWM/IGBT output mode, 10-bit A/D converter, LCD drive control circuit, and serial I/O. It operates at up to 16 MHz main clock frequency, supports 5 V supply, and targets embedded control in industrial and consumer equipment.

For engineers reviewing the M38C37ECMFS datasheet, M38C37ECMFS pinout, M38C37ECMFS application, or M38C37ECMFS equivalent, this page delivers verified package mapping (PLCC-68), confirmed pin functions, real-world use cases in motor control and sensor interface, and two validated alternative microcontrollers for design continuity.

Technical Context

The M38C37ECMFS implements the 740-family CPU core with 16-bit address space, supporting single-chip operation with internal ROM and RAM. Its peripheral set includes a 16-bit timer A with programmable PWM duty cycle and IGBT gate drive timing, plus a 10-bit successive-approximation A/D converter with 8 input channels and built-in sample-and-hold.

It integrates a dedicated LCD drive control circuit supporting static and multiplexed displays up to 4 commons × 16 segments, and a full-duplex UART-compatible serial I/O with selectable baud rates. Clock generation uses an external crystal (1–16 MHz) with internal division options (×1, ÷2, ÷8) for φ-clock output.

Key Specifications

Pinout & Package

Package: 68-pin Plastic Leaded Chip Carrier (PLCC-68), JEDEC MS-026AC compliant, body size 24.2 mm × 24.2 mm, 1.27 mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with M38C34M6AXXXFP and UPD78F0503GC-GAH-AX, the M38C37ECMFS uniquely combines mask-ROM security, hardware IGBT timing, and integrated LCD drive in a single PLCC-68 package - making it optimal for cost-sensitive, display-equipped motor control where field updates are not needed.

Availability

M38C37ECMFS is available at Aetrix Electronics and suitable for industrial motor control, smart appliance interfaces, programmable power monitors, and embedded HMI panels requiring stable component supply and long-term production continuity.

Supply support for M38C37ECMFS 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 automotive, industrial, and IoT applications.

The 38C3 Group - including the M38C37ECMFS - was designed for cost-effective, single-chip embedded control in industrial equipment and consumer appliances where integration of LCD, motor timing, and analog sensing reduces system complexity.

FAQ

What is the maximum operating frequency of the M38C37ECMFS?

The M38C37ECMFS supports a main clock input (XIN) up to 16 MHz. Its internal φ-clock can be configured as XIN, XIN/2, or XIN/8 - yielding maximum φ-clock frequencies of 16 MHz, 8 MHz, or 2 MHz respectively. The CPU executes instructions at φ-clock rate, so peak instruction throughput is 16 MIPS in double-speed mode. All timing specifications in the datasheet assume operation within these validated limits.

Does the M38C37ECMFS include on-chip debug capability?

No, the M38C37ECMFS does not feature on-chip debug interfaces such as JTAG or FINE. Development relies on external emulators compatible with the 740 Family, like the M30520EHE-100SP or M30520EHE-200SP, which connect via dedicated pins (TCLK, TDI, TDO). The M38C37ECMFS lacks dedicated debug pins or ROM-based monitor code - firmware validation must occur using emulator-assisted breakpoints and memory inspection.

What LCD configurations does the M38C37ECMFS support?

The M38C37ECMFS supports static (1/1 duty), 2-common (1/2 duty), 3-common (1/3 duty), and 4-common (1/4 duty) LCD drive modes. It provides up to 4 COM outputs (COM0–COM3) and 16 SEG outputs (SEG0–SEG15), enabling direct drive of displays up to 4×16 segments. Bias voltage is generated internally; no external resistors or capacitors are required for basic operation, though contrast adjustment may use external potentiometer on VLCD pin.

Is the A/D converter on the M38C37ECMFS differential-input capable?

No, the M38C37ECMFS A/D converter accepts only single-ended analog inputs on pins AN0 through AN7 (mapped to P20–P27). It does not support differential pair inputs or programmable gain amplification. Each channel is sampled against internal VREF (typically VCC), with conversion results stored as unsigned 10-bit values in ADRL/ADRH registers. External signal conditioning (e.g., instrumentation amps) is required for differential measurements.

What is the ROM size and type used in the M38C37ECMFS?

The M38C37ECMFS contains 64 KB of on-chip mask ROM. This ROM is factory-programmed during wafer fabrication and cannot be electrically erased or reprogrammed. It is intended for fixed, high-volume firmware deployments where security, reliability, and low unit cost are prioritized over field updates. No flash, EEPROM, or OTP variants exist for this specific part number.