MC705C8ACFNR2 - 8-Bit 2.1MHz OTP Microcontroller | NXP
MPN: MC705C8ACFNR2 ✓ Active| Qty | Unit Price | Extended |
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| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
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| 500 | $0 | $0.00 |
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MC705C8ACFNR2 Overview
The MC705C8ACFNR2 combines a small microcontroller core with 8 KB (8K x 8) of OTP program memory. Its 8-bit architecture supports control-oriented workloads, while the 2.1 MHz operating frequency provides a defined execution speed for legacy embedded systems. The device is supplied in a 44-pin plastic leaded chip carrier, commonly identified by package code QCCJ, with a square package shape and J-bend terminal form.
The supplied data identifies the part as a M68HC05 HC05 microcontroller with 8 KB OTP memory and a 2.1 MHz clock. An additional search result describes the related MC68HC705C8A technical family, but it does not provide a complete manufacturer specification table for this exact ordering code. Therefore, details such as RAM, I/O count, voltage range, timer resources, and electrical limits are retained as data-needed items rather than inferred from the family name.
Typical embedded-control uses include legacy appliance controls, industrial automation modules, motor and relay-control boards, panel interfaces, and small standalone embedded products. A designer should confirm the exact pin functions, memory map, clock configuration, peripheral availability, and operating voltage against the Motorola or NXP technical documentation before creating a new PCB or replacing an existing device.
The main design consideration is package and pin compatibility. The MC705C8ACFNR2 uses a 44-pin PLCC footprint, so a substitute must match the same package and pin arrangement, not merely offer similar processor performance. Existing firmware, memory organization, interrupt behavior, and peripheral mapping must also be validated before substitution.
This page consolidates the verified distributor identification, package data, memory and frequency details, sourcing links, and engineering caveats. It does not invent missing electrical specifications or assert an unqualified replacement recommendation without a verified pin-to-pin cross-reference.
Drop-in alternatives for MC705C8ACFNR2 — 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 MC705C8ACFNR2 (same form factor and footprint) — differing in Package, Program Memory, Mounting Type, Architecture, CPU Core.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC68HC705L32FU
✅ Drop-In✓ In Stock
$16.2097 / Unit
View Datasheet →MCHRC705J1ACDWE
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →MC68HC711MA8FU
✅ Drop-In✓ In Stock
$11.6 / Unit
View Datasheet →MC68HC16Z1MAG16
✅ Drop-In✓ In Stock
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View Datasheet →MC908AP32ACFBE
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View Datasheet →MC705C8ACFNR2 Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit microcontroller |
| Architecture | M68HC05 HC05 |
| CPU Bit Width | 8 bit |
| Operating Frequency | 2.1 MHz |
| Program Memory | 8 KB OTP (8K x 8) |
| Program Memory Type | One-time programmable memory |
| Package | 44-pin PLCC |
| Package Dimensions | 16.59 mm x 16.59 mm |
| Package Code | QCCJ |
| Terminal Form | J-bend |
| Number of Terminals | 44 |
| Temperature Grade | Industrial |
| Mounting Type | Through-hole leaded package |
| Manufacturer Family | M68HC05 |
| Related Technical Family | MC68HC705C8A |
MC705C8ACFNR2 qccj Pin Configuration Guide
Pin configuration for MC705C8ACFNR2 (qccj package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for MC705C8ACFNR2.
Refer to the datasheet for full pin configuration.
Typical Applications
MC705C8ACFNR2 is suitable for 6 applications: Legacy Appliance Control, Industrial Relay and Motor Control, Legacy Sensor Interface Module, Instrument Panel and Keypad Interface, Programmable Logic Controller, Legacy Communication Controller.
Legacy Appliance Control
The MC705C8ACFNR2 fits fixed appliance-control logic where an 8-bit processor, 2.1 MHz operating frequency, and 8 KB OTP program memory are sufficient for sequencing motors, relays, lamps, buttons, and sensors. OTP is useful for production firmware that is finalized before programming, while the 44-pin PLCC package supports through-hole assembly in legacy control boards. The designer must confirm the exact I/O map, voltage range, timer resources, and reset behavior before using it in a new design.
Recommended
Industrial Relay and Motor Control
The 8-bit M68HC05 architecture and 2.1 MHz clock make the MC705C8ACFNR2 a candidate for compact relay sequencing and small motor-control subsystems. A PLCC package provides a robust through-hole footprint for industrial control boards, but the external driver stage must handle load current, isolation, protection, and switching transients. Confirm timer, interrupt, I/O, and electrical-limit details against the exact MC705C8ACFNR2 datasheet before allocating control functions.
Recommended
Legacy Sensor Interface Module
Use the MC705C8ACFNR2 as the control processor for a small legacy sensor-interface board when fixed firmware and moderate processing requirements are sufficient. Its 8-bit architecture can coordinate digital inputs, indicator outputs, and simple control loops at 2.1 MHz. Because the supplied data does not specify ADC resources, communication peripherals, RAM, or exact I/O count, these functions must be verified from the manufacturer documentation rather than assumed.
Recommended
Instrument Panel and Keypad Interface
The MC705C8ACFNR2 is applicable to fixed-function panel systems requiring button scanning, LEDs, interlocks, and simple state-machine control. Its 2.1 MHz operating frequency provides a defined execution basis for deterministic control logic, and the 44-pin PLCC package is compatible with through-hole panel boards. The exact number and electrical characteristics of I/O pins are not present in the verified sources, so panel assignment must wait for pin-level and timing verification.
Recommended
Programmable Logic Controller
The M68HC05 HC05 architecture can suit small legacy PLC or automation-controller nodes when the application is primarily discrete I/O, sequencing, and fixed logic. The 8 KB OTP memory supports a finite control program, while the 2.1 MHz clock supports basic instruction execution. Before deployment, verify RAM, watchdog behavior, communication interfaces, isolation, input thresholds, output drive capability, and industrial temperature behavior against the exact device documentation.
Recommended
Legacy Communication Controller
The MC705C8ACFNR2 may be considered for a dedicated legacy communication-control node if its undocumented or application-specific peripherals match the system requirements. Its fixed 8-bit, 2.1 MHz architecture is suitable for protocol framing, state management, and supervisory control, but no UART, SPI, I2C, or CAN capability is confirmed in the supplied data. Treat the part as a legacy design-retention component and verify interface pin multiplexing, timing, and electrical characteristics before use.
Recommended
Recommended Products Summary
Engineering reference data for MC705C8ACFNR2 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC68HC705L32FU | MCHRC705J1ACDWE | MC68HC711MA8FU | MC68HC16Z1MAG16 | MC908AP32ACFBE |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | Freescale Semiconductor | Freescale Semiconductor | Freescale Semiconductor | Freescale Semiconductor | Freescale Semiconductor |
| Package | 44-pin PLCC | PLCC-44 | PLCC-44 | PLCC-44 | PLCC-44 | PLCC-44 |
Key Differentiators
- Target package and pin-count constraint (vs MC68HC705L32FU)
- Program-memory implementation (vs MCHRC705J1ACDWE)
- Defined 8-bit, 2.1 MHz target specification (vs MC68HC711MA8FU)
Design Notes
Do not treat the M68HC05 family name as proof of drop-in compatibility. The verified data identifies the target as an 8-bit 2.1 MHz part with 8 KB OTP memory in a 44-pin PLCC, but it does not provide the complete pinout or electrical table. Before substitution, compare every pin, alternate function, supply requirement, reset pin, clock requirement, memory map, and programming method with the exact candidate datasheet.
Design the PCB around the 44-pin PLCC footprint rather than a generic 44-pin package. Verify body size, lead pitch, pin numbering, J-bend geometry, solderable area, and assembly clearance against the package drawing. Because the verified sources identify QCCJ and J-bend construction, mechanical interchangeability must be checked separately from electrical compatibility.
Supply rails and decoupling must be selected only after the exact operating-voltage and decoupling requirements are confirmed from the manufacturer datasheet. The supplied data does not include input voltage, absolute maximum ratings, or current limits, so those values are intentionally marked as data-needed. Do not infer them from the 2.1 MHz clock or from the M68HC705 family description.
The 44-pin PLCC is a through-hole package, and its thermal performance depends on copper area, airflow, lead construction, and the surrounding board. No junction-to-ambient resistance or power dissipation limit was supplied, so thermal calculations cannot be made responsibly from the available data. For production, derive the worst-case dissipation from verified operating current and voltage limits, then check the manufacturer’s thermal rating and assembly conditions.
OTP programming is a permanent manufacturing step. Validate the programming fixture, programming voltage, timing, blank-device handling, and post-program verification before releasing production units. Firmware changes after programming require a new programmed device; do not design the system around an assumed field-update path.
Compliance Information
The verified search results identify an industrial temperature grade but do not provide RoHS, REACH, lead-free, halogen-free, or conflict-minerals declarations. AEC-Q100 is not stated for this exact ordering code.
