PIC12C508AT-04E/SN - 8-bit OTP MCU, 768B, 4MHz, SOIC-8 | Microchip
MPN: PIC12C508AT-04E/SN ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.55 | $1.55 |
| 10 | $1.4 | $14.00 |
| 100 | $1.2 | $120.00 |
| 500 | $1.05 | $525.00 |
| 1,000 | $0.95 | $950.00 |
| 2,500 | $0.85 | $2,125.00 |
PIC12C508AT-04E/SN Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program and data memory, and programmable I/O peripherals. The PIC12C508A belongs to the Microchip PIC10/12 family of small-form-factor 8-pin controllers, positioned within the broader category of microcontrollers -> microprocessors -> embedded computing -> semiconductors. These compact MCUs are the lowest-cost entry point into the PIC ecosystem and are widely deployed as glue logic replacement, sensor interface controllers, and standalone timed-control supervisors.
Key features include 6 bidirectional I/O pins, an 8-bit real-time counter (TMR0) with an 8-bit programmable prescaler, Power-On Reset (POR), Device Reset Timer (DRT), a Watchdog Timer (WDT) with its own dedicated on-chip RC oscillator, programmable code protection, and 1,000,000 erase/write cycles typical endurance. The extended (-40C to +125C) operating temperature range and 3.0V-5.5V supply range make it suitable for harsh industrial environments.
The PIC12C5XX architecture implements Harvard-style separate program/data paths with a 12-bit instruction word, achieving approximately 2:1 code compression over typical 8-bit microcontrollers. Its baseline core omits hardware interrupts, prioritizing code density and deterministic timing over peripheral integration - the result is a low-cost deterministic engine for tightly looped timing or state-machine tasks.
Typical applications include appliance control, automotive sensor interfaces, simple sensor signal conditioning, low-cost timing controllers, and small logic replacements where an MCU adds flexibility at lower BOM cost than discrete logic. The 4 MHz internal RC option enables a clockless BOM in cost-sensitive designs.
When designing, ensure Vdd decoupling uses a 0.1uF ceramic capacitor placed within 5 mm of the Vdd pin. MCLR must be tied to Vdd through a pull-up if not used externally to prevent spurious resets. With only six usable I/O, careful pin budgeting at the schematic stage is critical.
This page synthesizes distributor pricing, drop-in alternatives, pin-by-pin replacement guidance, and design notes not found aggregated in the manufacturer datasheet.
Drop-in alternatives for PIC12C508AT-04E/SN — 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 PIC12C508AT-04E/SN (same form factor and footprint) — differing in Instruction Execution Time, Package, Program Memory Size, RAM Size, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC12C508A-04E/SN
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12C508AT-04I/SN
✅ Drop-In✓ In Stock
$1.4 / Unit
View Datasheet →PIC12C508AT-04/SN
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12C508AT-04E/SM
✅ Drop-In✓ In Stock
$0.36 / Unit
View Datasheet →PIC12C508A-04I/SM
✅ Drop-In✓ In Stock
$1.05 / Unit
View Datasheet →PIC12C508AT-04E/SN Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology |
| Series | PIC 12C |
| Core | PIC |
| Core Size | 8-bit |
| Instruction Word Width | 12-bit |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 768 bytes (512 x 12) |
| RAM Size | 25 bytes |
| Maximum Clock Speed | 4 MHz |
| Number of I/O Pins | 6 |
| Timers | 8-bit TMR0 with 8-bit programmable prescaler |
| Watchdog Timer | Yes, with dedicated on-chip RC oscillator |
| Supply Voltage Range | 3.0 V to 5.5 V |
| Operating Temperature Range | -40C to +125C (extended) |
| Package | 8-pin SOIC (SN) |
| Mounting Type | Surface Mount |
| Instruction Set Size | 33 single-word instructions |
| Instruction Execution Time | 1 microsecond at 4 MHz |
| Erase/Write Endurance | 1,000,000 cycles typical |
| Code Protection | Programmable |
| RoHS Status | Compliant |
PIC12C508AT-04E/SN Pin Configuration
| Pin 1 | GP5/OSC1/CLKIN — Bidirectional I/O pin / oscillator crystal input / external clock input |
| Pin 2 | GP3/MCLR/Vpp — Bidirectional I/O / Master Clear reset input (active low) / programming voltage |
| Pin 3 | GP4/OSC2/CLKOUT — Bidirectional I/O / oscillator crystal output / clock output |
| Pin 4 | Vss — Ground reference |
| Pin 5 | GP0 — Bidirectional I/O pin 0 |
| Pin 6 | GP1 — Bidirectional I/O pin 1 |
| Pin 7 | GP2/T0CKI — Bidirectional I/O / Timer 0 clock input |
| Pin 8 | Vdd — Positive supply voltage (3.0V to 5.5V) |
Typical Applications
PIC12C508AT-04E/SN is suitable for 7 applications: Appliance Control and Replacement Logic, Automotive Sensor Interface and Body Electronics, Low-Cost Sensor Signal Conditioning, Standalone Timing and Pulse Generation Controllers, Small Logic Replacement and Glue Logic Consolidation, LED Lighting Controllers and Sequencers, Remote Control and IR Encoder Sub-Systems.
Appliance Control and Replacement Logic
The PIC12C508AT-04E/SN fits appliance control applications because its 768 bytes of OTP program memory is sufficient for state-machine-based controllers (washing machine timers, dishwasher cycles, microwave user interfaces). The 4 MHz core delivers 1 MIPS, enough to scan a 4x4 keypad matrix and drive relay outputs within tens of milliseconds. Six I/O pins support key scanning, LED indicator drive, and one relay/buzzer control. With -40C to +125C extended temperature operation the part survives under-hood or steamy kitchen environments. The watchdog timer with dedicated RC oscillator catches lockup conditions without external components. Compared to discrete 555-timer or CMOS-logic implementations, this MCU replaces dozens of logic gates with a single 8-pin IC at lower BOM cost. XAIPART recommends pairing this MCU with the MCP1700 LDO for 3.3V regulation.
Recommended
Automotive Sensor Interface and Body Electronics
The PIC12C508AT-04E/SN is well-suited for automotive sensor interface modules because its 4 MHz core, 6 I/O pins, and -40C to +125C extended temperature range meet under-hood and cabin electronics requirements. The MCU can debounce switch inputs, multiplex analog sensors via external ADC, or generate PWM control signals for small actuators. Its TMR0 with 8-bit programmable prescaler supports accurate timing for window-lift or mirror-fold sequencing. The on-chip watchdog timer with its own dedicated RC oscillator ensures reliable operation even if the main oscillator fails - critical for automotive functional safety. OTP memory prevents firmware tampering. Compact 8-pin SOIC footprint fits behind dashboard switches and inside door modules where space is constrained. XAIPART also carries the PIC12C508A-04E/SM in SOIJ package for vibration-prone mounting.
Recommended
Low-Cost Sensor Signal Conditioning
The PIC12C508AT-04E/SN works as a sensor signal-conditioning front end for thermistor, photodiode, or simple switch inputs. Its 25 bytes of RAM accommodate short moving-average filters for noise rejection, and the 768-byte program memory stores calibration constants and linearization tables. Six I/O pins handle analog input via on-chip comparator (where available), digital I/O, and UART-software-emulated output to a host MCU. The 4 MHz instruction rate supports sampling rates up to 100 kHz when required. Operating voltage from 3.0V to 5.5V allows direct connection to 3.3V or 5V sensor rails without level shifting. The extended -40C to +125C range supports outdoor and industrial deployments.
Recommended
Standalone Timing and Pulse Generation Controllers
The PIC12C508AT-04E/SN serves as a dedicated timing controller in industrial automation because its 8-bit TMR0 with programmable prescaler delivers microsecond-resolution timing at 4 MHz. Six I/O pins support up to three independent PWM channels via software, or one PWM plus serial output plus enable logic. The dedicated watchdog RC oscillator ensures timing integrity even during main-oscillator failure. OTP code protection prevents unauthorized timing parameter modification. The 8-pin SOIC package mounts directly on DIN-rail or terminal-block carrier boards. 1 MIPS performance is sufficient for timing-critical PLC interlock replacement. Compared to dedicated timer ICs like 555 or TLC555, this MCU provides programmable flexibility with similar cost.
Recommended
Small Logic Replacement and Glue Logic Consolidation
The PIC12C508AT-04E/SN consolidates discrete CMOS logic gates (74HC00, 74HC04, 74HC32 families) into a single 8-pin package when state-machine complexity exceeds simple combinational logic. Six I/O pins can replace 3-4 small-scale logic ICs at lower BOM cost and PCB area. The 768-byte program memory and 33-instruction PIC RISC core are simple enough that firmware development is faster than schematic capture for complex glue logic. The 4 MHz clock delivers deterministic 1 microsecond instruction timing. OTP memory ensures the design cannot be reverse-engineered by reading the part. Extended temperature grade supports industrial environments. XAIPART recommends this approach when discrete logic parts exceed 3 ICs or when configurability via firmware is desired.
Recommended
LED Lighting Controllers and Sequencers
The PIC12C508AT-04E/SN drives LED lighting controllers for decorative, automotive accent, or signage applications. Six I/O pins support up to six independent LED channels via direct drive or external transistor switching. The 4 MHz core and TMR0 with prescaler generate accurate PWM dimming at frequencies above 100 Hz to avoid flicker perception. 768 bytes of OTP memory stores complex chase, fade, and color-mixing patterns. The -40C to +125C extended temperature range tolerates under-hood or outdoor signage environments. Operating voltage from 3.0V to 5.5V is compatible with constant-current LED driver ICs like MCP1640 or MCP3911. Code protection prevents unauthorized pattern modification. The 8-pin SOIC package fits inside compact RGB strip controllers.
Recommended
Remote Control and IR Encoder Sub-Systems
The PIC12C508AT-04E/SN implements IR remote control encoders (RC5, NEC, Sony SIRC) for TV, set-top box, or smart-home control applications. Six I/O pins support one IR LED output (via external transistor), one or two switch inputs, and one status LED. The 4 MHz instruction cycle produces accurate carrier frequencies (36-40 kHz typical) via software PWM with TMR0 prescaler. 768 bytes of OTP memory stores multiple protocol encoders and key code mappings. The compact 8-pin SOIC fits inside AAA-battery-powered remote housings. Power consumption is low because the PIC12C5XX core draws under 2 mA active at 4 MHz. Code protection prevents firmware cloning. XAIPART also stocks PIC10F322 for flash-based designs with more protocol storage.
Recommended
Recommended Products Summary
Engineering reference data for PIC12C508AT-04E/SN — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC12C508A-04E/SN | PIC12C508AT-04I/SN | PIC12C508AT-04/SN |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 8-pin SOIC (SN) | 8-pin SOIC (SN) - same | 8-pin SOIC (SN) - same | 8-pin SOIC (SN) - same |
| Program Memory | 768 B OTP (512 x 12) | 768 B OTP - same | 768 B OTP - same | 768 B OTP - same |
| Maximum Clock Speed | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| RAM Size | 25 B | 25 B | 25 B | 25 B |
| I/O Pins | 6 | 6 | 6 | 6 |
| Operating Temperature | -40C to +125C (extended) | -40C to +85C (industrial) | -40C to +85C (industrial) | 0C to +70C (commercial) |
| Memory Type | OTP | OTP | OTP | OTP |
Key Differentiators
- Extended temperature range vs commercial-grade alternatives (vs PIC12C508AT-04/SN)
- Enhanced silicon revision with wider supply range (vs PIC12C508 (non-A))
- OTP code protection prevents firmware cloning (vs PIC12C508A-04E/SN (industrial grade))
- Mature Microchip ecosystem with full toolchain (vs Cross-brand 8-bit MCU alternatives)
Design Notes
Place a 0.1uF ceramic decoupling capacitor within 5 mm of the Vdd pin (pin 8) with a direct trace to the ground plane. For designs exposed to motor or relay noise, add a 10uF tantalum or aluminum polymer bulk capacitor at the MCU Vdd node. The PIC12C5XX core draws under 2 mA active at 4 MHz and 1 uA typical sleep current, so a small MCP1700 LDO is sufficient as the supply source.
Pin 2 (GP3/MCLR/Vpp) must be tied to Vdd through a 10 kohm pull-up resistor if not driven by an external reset supervisor. A floating MCLR pin will trigger spurious resets in noisy environments. For OTP programming via PICkit, the MCLR pin must reach 13V nominal at Vpp - leave space for a programming header or pogo-pad footprint. Keep oscillator traces (OSC1/OSC2) short and away from high-current switching traces to minimize EMI injection.
Do not connect any load greater than 25 mA per I/O pin or 50 mA total Vdd supply current - the PIC12C5XX I/O drive is weak by modern standards. Do not assume the GP3 pin can be used as a normal output - it is an open-drain only input/output on this device. Do not omit the OPTION register configuration for TMR0 prescaler - the default watchdog behavior may consume more current than expected. Verify your linker/assembler version supports PIC12C508A OTP programming before committing to firmware builds.
At maximum 4 MHz clock with all 6 I/O pins driving 20 mA loads, the PIC12C508AT-04E/SN in 8-pin SOIC dissipates approximately 200 mW. The theta_JA of 150 C/W for SOIC-8 yields a junction temperature rise of 30C above ambient - well within the -40C to +125C rating. However, in sealed enclosures without airflow, derate I/O loading or add a thermal via to a copper pour on pin 4 (Vss) and pin 8 (Vdd) for heat spreading.
Compliance Information
RoHS and lead-free compliant per Microchip product page. AEC-Q100 not qualified - this part targets industrial/commercial applications. The 'E' suffix denotes extended temperature grade per Microchip nomenclature.
