PIC12C672-04/P - 8-Bit 4MHz OTP MCU with ADC | Microchip
MPN: PIC12C672-04/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.55 | $25.50 |
| 100 | $2.2 | $220.00 |
| 500 | $1.95 | $975.00 |
| 1,000 | $1.72 | $1,720.00 |
PIC12C672-04/P Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory, working RAM, and peripheral interfaces such as ADC, timers, and I/O ports. The PIC12C672 sits within the broader taxonomy of microcontroller -> 8-bit microcontroller -> RISC microcontroller -> embedded controller -> semiconductor. Its Harvard architecture, separate program and data buses, and 14-bit instruction word place it firmly in Microchip's mid-1990s mid-range PIC family, optimized for cost-sensitive analog-sensing and control applications.
Key features include an internal 4 MHz oscillator option (or external clock), a 4-channel 8-bit ADC, an 8-bit timer/counter with prescaler, a watchdog timer with its own on-chip RC oscillator, and an operating voltage range of 2.5 V to 5.5 V (extended) or 3.0 V to 5.5 V (commercial/industrial). The device offers low power consumption with typical sleep currents below 1 microampere, programmable weak pull-ups on GPIO, and code protection to safeguard intellectual property.
The PIC12C672 uses a RISC pipelined architecture with a 14-bit program word, allowing most instructions to execute in a single 200 ns instruction cycle at 20 MHz (or 1 microsecond at 4 MHz). This combines predictable interrupt latency with deterministic throughput for sensor reading and PWM-style bit-banging. The integrated ADC samples up to four channels with 8-bit resolution, suitable for thermistor, potentiometer, and battery-monitoring inputs.
Typical applications include battery chargers, smoke detectors, sensor conditioning front-ends, low-end remote controls, appliance timers, and any cost-constrained embedded design requiring modest analog inputs. The 8-pin PDIP format supports easy breadboarding, hobbyist projects, and legacy through-hole PCB layouts.
When designing with this part, consider that the OTP memory cannot be re-programmed, so firmware revisions require a new part. Migration to flash-based PIC10F/PIC12F/PIC16F equivalents (such as PIC12F675 with comparable pinout) is recommended for new designs. Decoupling capacitors of 0.1 microfarad should be placed close to VDD with a 10 microfarad bulk capacitor on the supply rail.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC12C672-04/P — 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 PIC12C672-04/P (same form factor and footprint) — differing in Package, Program Memory Size, Watchdog Timer, Operating Temperature, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC12C672-10/P
✅ Drop-In✓ In Stock
$1.99 / Unit
View Datasheet →PIC12C672-04E/P
✅ Drop-In✓ In Stock
$2.3 / Unit
View Datasheet →PIC12C671-04/P
✅ Drop-In✓ In Stock
$1.5 / Unit
View Datasheet →PIC12F675-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12CE674-04/P
✅ Drop-In✓ In Stock
$1.85 / Unit
View Datasheet →PIC12C509A-04/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12C672-04/P Maximum Ratings & Electrical Characteristics
| Core | PIC 8-bit RISC |
| Program Memory Size | 3.5 KB (2K x 14) OTP |
| RAM Size | 128 B |
| EEPROM | None (ROMless data) |
| Maximum Clock Speed | 4 MHz |
| Instruction Cycle Time | 1 microsecond at 4 MHz |
| Number of I/O Pins | 6 |
| ADC | 8-bit, 4 channels |
| Timers | 1 x 8-bit with prescaler |
| Watchdog Timer | Yes, with dedicated RC oscillator |
| Supply Voltage | 2.5 V to 5.5 V (extended); 3.0 V to 5.5 V (commercial/industrial) |
| Supply Current (sleep) | Typical < 1 microampere |
| Operating Temperature | -40C to +85C (industrial) |
| Package | PDIP-8 (through-hole, 0.300 inch / 7.62 mm pitch) |
| Mounting Type | Through-Hole |
| MSL Level | 1 (unlimited) |
| RoHS Status | Compliant |
PIC12C672-04/P Pin Configuration
| Pin 1 | VDD — Positive supply voltage |
| Pin 2 | GP5/OSC1/CLKIN — GPIO5 / oscillator input / external clock input |
| Pin 3 | GP4/OSC2/CLKOUT — GPIO4 / oscillator output / clock output |
| Pin 4 | GP3/MCLR/VPP — GPIO3 / master clear reset / programming voltage input |
| Pin 5 | GP2/AN2 — GPIO2 / analog input channel 2 |
| Pin 6 | GP1/AN1 — GPIO1 / analog input channel 1 |
| Pin 7 | GP0/AN0 — GPIO0 / analog input channel 0 |
| Pin 8 | VSS — Ground reference |
Typical Applications
PIC12C672-04/P is suitable for 6 applications: Battery Charger Controller, Smoke and CO Detector Front-End, Remote Control Transmitter, Appliance Timer and Sequencer, Sensor Signal Conditioning and Transmitter, Hobbyist and Educational Embedded Platform.
Battery Charger Controller
The PIC12C672-04/P is well suited for low-cost NiCd/NiMH/Li-ion charger controllers where its 4-channel 8-bit ADC monitors battery voltage and current. The on-chip ADC samples thermistor and shunt-resistor voltages to implement CC-CV charge termination, while the 8-bit timer drives PWM control of the pass element. With 3.5 KB of OTP memory, designers can implement state-machine charge profiles, delta-V detection, and safety timers without external logic. Operating from 2.5 V to 5.5 V, the PIC12C672 runs directly from the battery stack. Compared with discrete charger ICs, this approach adds firmware flexibility (custom cell chemistries, temperature derating, LED status) at the cost of OTP-only programming.
Recommended
Smoke and CO Detector Front-End
Smoke and carbon-monoxide detectors benefit from the PIC12C672-04/P's combination of low sleep current (under 1 microampere), 4-channel ADC for photoelectric-chamber and CO-sensor readout, and 6 GPIO for buzzer, LED, hush, and interconnect wiring. The 8-bit core runs a periodic sample-and-decide loop checking the ionization-chamber or CO-cell voltage against programmable thresholds. The watchdog timer with dedicated RC oscillator provides fail-safe operation during firmware lockup. Operating from a 9 V battery stepped down to 5 V, the part's 2.5 V to 5.5 V range supports multi-year battery life. Designers should note the OTP memory constraint and plan a last-time-buy strategy when migrating to PIC12F675 flash variants.
Recommended
Remote Control Transmitter
Infrared and sub-GHz remote controls leverage the PIC12C672-04/P's compact 8-pin PDIP package, modest 3.5 KB program memory, and 6 GPIO for key matrix scanning plus IR-LED drive. The PIC's 1 microsecond instruction cycle at 4 MHz supports Manchester or pulse-position modulation at 38 kHz carrier without external timing circuitry. The integrated 8-bit ADC can read battery voltage for low-battery indication, eliminating a discrete voltage supervisor. OTP memory is acceptable because remote-control firmware rarely changes after release. The 2.5 V to 5.5 V operating range supports 3 V coin-cell and 4.5 V three-AAA battery configurations. Designers targeting cost-down can drop to PIC12C509A-04/P if ADC monitoring is not required.
Recommended
Appliance Timer and Sequencer
Appliance timer modules (washing-machine delays, dishwasher cycle sequencers, oven timers) use the PIC12C672-04/P's 8-bit timer with prescaler and 4-channel ADC for temperature or water-level sensing. The 6 GPIO drive relays, triac optocouplers, and segment LEDs without external logic. Operating from 5 V via a small linear regulator, the part handles brownout conditions down to 2.5 V while preserving RAM via the brown-out reset circuit. The 3.5 KB OTP holds complex state-machine firmware for multi-stage cycles. The 8-pin PDIP through-hole format simplifies assembly for low-volume appliance SKUs. Migration path to PIC12F675-I/P offers field-upgradeable firmware and an internal oscillator.
Recommended
Sensor Signal Conditioning and Transmitter
Industrial 4-20 mA loop-powered transmitters and sensor signal conditioners use the PIC12C672-04/P to digitize bridge, thermistor, or RTD inputs and drive a PWM-based loop modulator. The 8-bit ADC samples at up to 30 ksps with 4 input channels, sufficient for temperature, pressure, and strain-gauge front-ends after external instrumentation-amp conditioning. With 3.5 KB of OTP, designers implement linearization, fault detection, and HART or proprietary communication protocols. The 2.5 V minimum supply supports operation from 3.3 V loops. The 6 GPIO drive the loop transistor, calibration switches, and diagnostic LEDs. The PIC12C672-04E/P variant extends operating temperature to 125C for harsh-environment industrial applications.
Recommended
Hobbyist and Educational Embedded Platform
The PIC12C672-04/P remains a popular choice in university embedded-systems courses and hobbyist projects because of its 8-pin PDIP breadboard-friendly footprint, low cost, and availability of Microchip's MPLAB IDE plus PICkit programmers. The 35-instruction RISC core teaches assembly fundamentals (program counter, W register, banked RAM) without overwhelming beginners. The 4-channel 8-bit ADC introduces students to analog sampling, while 6 GPIO exercise bit manipulation and interrupt handling. With 3.5 KB OTP, the part fits classic coursework examples (LED chaser, temperature logger, IR decoder). For modern courses, Microchip recommends PIC12F675-I/P which adds flash and an internal oscillator for easier iteration without an external resonator.
Recommended
Recommended Products Summary
Engineering reference data for PIC12C672-04/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC12C672-10/P | PIC12C672-04E/P | PIC12C671-04/P | PIC12F675-I/P | PIC12CE674-04/P | PIC12C509A-04/P |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | PDIP-8 | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same |
| Maximum Clock | 4 MHz | 10 MHz (+150%) | 4 MHz (same) | 4 MHz (same) | 20 MHz (+400%) | 4 MHz (same) | 4 MHz (same) |
| Program Memory | 3.5 KB OTP | 3.5 KB OTP (same) | 3.5 KB OTP (same) | 1.75 KB OTP (-50%) | 1.75 KB Flash (reprog) | 3.5 KB OTP (same) | 1.5 KB OTP (-57%) |
| RAM | 128 B | 128 B (same) | 128 B (same) | 128 B (same) | 64 B (-50%) | 128 B (same) | 41 B (-68%) |
| ADC | 8-bit, 4 channels | 8-bit, 4 channels (same) | 8-bit, 4 channels (same) | 8-bit, 4 channels (same) | 10-bit, 4 channels (better) | 8-bit, 4 channels (same) | None |
| EEPROM Data Memory | None | None (same) | None (same) | None (same) | 128 B (better) | 16 B (better) | None (same) |
| Memory Type | OTP (one-time) | OTP (same) | OTP (same) | OTP (same) | Flash (reprog, upgrade) | OTP (same) | OTP (same) |
Key Differentiators
- Balanced OTP memory size for embedded control (vs PIC12C671-04/P)
- Drop-in speed upgrade path available (vs PIC12C672-10/P)
- Flash upgrade path exists on the same footprint (vs PIC12F675-I/P)
Design Notes
Place a 0.1 microfarad decoupling capacitor within 5 mm of the VDD pin (pin 1) and a 10 microfarad bulk capacitor on the supply rail. According to the Microchip datasheet (DS40139), the brown-out reset threshold is configurable; for battery applications operating down to 2.5 V, set BOR to the lowest setting to prevent unintended resets. Avoid sharing the digital VDD with analog reference if precision ADC readings are required.
The PIC12C672-04/P uses One-Time-Programmable memory, meaning any code revision requires a new physical device. This is the most common pitfall when migrating from flash-based PIC12F/PIC16F designs. Designers should plan firmware freezes early, validate on PIC12F675-I/P (pin-compatible flash equivalent), and only freeze the OTP image after the design is fully validated. Factory programming via Microchip's ICSP service is recommended for production volumes.
For the 8-pin PDIP package, route MCLR/VPP (pin 4) directly to a 10 kohm pull-up resistor to VDD; do not leave it floating. If in-circuit serial programming is desired, add a 4.7 kohm pull-up to MCLR and a programming header. The OSC1/OSC2 pins (2 and 3) should be kept short; when using a crystal resonator, place load capacitors (typically 15-33 pF) within 5 mm of the package. Avoid running high-current traces under the IC to minimize digital noise coupling into the ADC inputs.
Compliance Information
RoHS and REACH compliance per Microchip product page. AEC-Q100 not applicable (consumer/industrial microcontroller, not automotive qualified). Lead-free (Pb-free) per Microchip packaging specification. Halogen-free status not explicitly stated in available data.
