PIC12C508T-04/SM - 8-Bit 4MHz OTP MCU 768B | Microchip
MPN: PIC12C508T-04/SM ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.85 | $1.85 |
| 10 | $1.66 | $16.60 |
| 100 | $1.48 | $148.00 |
| 500 | $1.32 | $660.00 |
| 1,000 | $1.18 | $1,180.00 |
PIC12C508T-04/SM Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates an 8-bit CPU core, program memory (ROM/EPROM/Flash/OTP), data RAM, and peripheral interfaces such as I/O ports, timers, and sometimes comparators or ADCs. PIC microcontrollers specifically use a RISC (Reduced Instruction Set Computer) Harvard architecture where program and data buses are separate, enabling single-cycle instruction execution and deterministic timing. The PIC12C5xx family sits within the broader category of 8-bit microcontrollers > RISC microcontrollers > embedded controllers > semiconductor ICs, and is intended for cost-sensitive, low-pin-count logic-replacement and simple-control applications.
Key features include 33 single-word/single-cycle instructions, 2:1 code compression versus other 8-bit MCUs in its class, six I/O pins, one 8-bit timer/counter (TMR0) with 8-bit prescaler, watchdog timer with its own on-chip RC oscillator, power-on reset, brown-out detection, and an operating voltage range of 2.5 V to 5.5 V. The device operates over the commercial 0 °C to +70 °C temperature range and supports in-circuit serial programming (ICSP) via the GP0/GP1 pins. Its CMOS design delivers low power consumption suitable for both battery- and line-powered embedded systems.
The PIC12C508T-04/SM uses a 12-bit instruction word and Harvard architecture with only two addressing modes, which together simplify programming while maintaining high code density. Built on Microchip's mature CMOS process, this device is designed for high reliability in consumer and industrial environments, with ESD protection and latch-up immunity that exceeds typical automotive and industrial standards. The 8-SOIJ package provides a compact 3.90 mm body, making it one of the smallest 8-pin microcontrollers available for surface-mount designs.
Typical applications include consumer electronics (remote controls, toys, small appliances), white goods control panels, sensor signal conditioning and timing, automotive interior accessories (non-safety-critical), low-end logic replacement (substituting 555 timers and discrete logic gates with software-driven flexibility), battery-powered devices, and simple industrial controllers. Its 6 available I/O pins are sufficient for applications that drive a few LEDs, read a switch matrix, or talk to a single peripheral via bit-banged protocols.
When designing with this part, ensure decoupling capacitors are placed close to VDD with a 0.1 µF ceramic recommended. Because it uses OTP memory, code must be fully verified before programming; consider the PIC12F508 (Flash-based) if in-field reprogrammability is required. Note that this part is mature/NRND and may have longer lead times - confirm availability before committing to high-volume designs.
This page synthesizes distributor pricing, pin-compatible drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC12C508T-04/SM — 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 PIC12C508T-04/SM (same form factor and footprint) — differing in Package, Program Memory Size, Timers, Watchdog Timer, Brown-out Reset.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC12C508-04/SM
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12C508T-04I/SM
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12C508A-04/SM
✅ Drop-In✓ In Stock
$1.18 / Unit
View Datasheet →PIC12C508AT-04E/SM
✅ Drop-In✓ In Stock
$0.36 / Unit
View Datasheet →PIC12F508-I/SN
✅ Drop-In✓ In Stock
$0.31 / Unit
View Datasheet →PIC12C508T-04/SM Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit RISC PIC |
| Family | PIC12C5xx |
| Maximum Clock Frequency | 4 MHz |
| Program Memory Size | 768 B (512 x 12-bit words) OTP |
| RAM Size | 25 B |
| Operating Voltage Range | 2.5 V to 5.5 V |
| I/O Pins | 6 |
| Timers | 1 x 8-bit (TMR0 with prescaler) |
| Watchdog Timer | Yes (with dedicated on-chip RC oscillator) |
| Instruction Set | 33 single-word/single-cycle instructions |
| Program Memory Type | OTP (One-Time-Programmable) EPROM |
| Brown-out Reset | Yes |
| Power-on Reset | Yes |
| In-Circuit Serial Programming (ICSP) | Yes (via GP0/GP1) |
| Operating Temperature Range | 0 °C to +70 °C (commercial) |
| Package | 8-SOIJ (3.90 mm body, tape & reel) |
| Mounting Type | Surface Mount |
PIC12C508T-04/SM Pin Configuration
| Pin 1 | GP5/OSC1/CLKIN — General-purpose I/O / oscillator input / external clock input |
| Pin 2 | GP4/OSC2 — General-purpose I/O / oscillator output |
| Pin 3 | GP3/MCLR/VPP — Input-only GP3 / master clear (reset) / programming voltage |
| Pin 4 | VSS — Ground reference |
| Pin 5 | GP0/ICSPDAT — General-purpose I/O / ICSP data |
| Pin 6 | GP1/ICSPCLK — General-purpose I/O / ICSP clock |
| Pin 7 | GP2/T0CKI/INT/COUT — General-purpose I/O / TMR0 clock input / external interrupt / comparator output |
| Pin 8 | VDD — Positive supply voltage (2.5 V to 5.5 V) |
Typical Applications
PIC12C508T-04/SM is suitable for 6 applications: Consumer Remote Control, Toy and Hobby Electronics, White Goods and Appliance Controllers, Logic Replacement and 555 Timer Substitution, Sensor Signal Conditioning and Timing, Battery-Powered Devices.
Consumer Remote Control
The PIC12C508T-04/SM fits low-end IR remote control designs because its 6 I/O pins are sufficient to drive an IR LED, read a 4x3 button matrix, and provide a status LED, all within 768 bytes of OTP program memory. Its 4 MHz core delivers deterministic 1 µs instruction cycles, critical for generating accurate 38 kHz / 40 kHz IR carrier frequencies via software PWM. The 2.5 V to 5.5 V operating range allows direct connection to two AAA cells without a boost converter. Compared to discrete 555-timer-based remotes, this MCU reduces BOM count, simplifies timing adjustment via firmware, and adds intelligent features such as auto power-off.
Recommended
Toy and Hobby Electronics
The PIC12C508T-04/SM is well-suited for toys and hobby electronics where low unit cost, small 8-SOIJ footprint, and 6 I/O pins provide enough flexibility for sound, light, and motor control. Its 25 bytes of RAM and 768-byte OTP program memory fit typical sound-effect playback, LED chase patterns, and servo pulse generation tasks. Brown-out reset protects against battery droop in children's toys, and the wide 2.5 V to 5.5 V supply range supports both alkaline and NiMH chemistries. Compared to logic-gate implementations, this part enables feature upgrades via firmware-only changes.
Recommended
White Goods and Appliance Controllers
The PIC12C508T-04/SM serves as a cost-optimized controller in white goods (washing machines, dishwashers, microwave ovens) and small appliances (coffee makers, toasters, fans) where simple timing, sequencing, and load switching are needed. The watchdog timer with its own on-chip RC oscillator ensures the controller recovers from firmware or ESD upsets - critical for unattended appliance operation. With 4 MHz operation and an 8-bit timer with prescaler, the device accurately generates control loop periods from milliseconds to minutes. The OTP memory prevents end-user firmware tampering while keeping unit cost below Flash-based MCUs.
Recommended
Logic Replacement and 555 Timer Substitution
The PIC12C508T-04/SM is a classic logic-replacement MCU, substituting 555 timers, NE555-based astable/monostable circuits, and discrete logic-gate networks in cost-sensitive designs. At a comparable unit cost, it provides software-configurable timing that eliminates trim pots and precision capacitors. A single PIC12C508 can replace multiple 555s in sequencing applications because its 768-byte program memory supports state-machine implementations. The 2.5 V to 5.5 V supply matches legacy 5 V analog designs, and the 8-SOIJ package fits existing 8-pin DIP and SOIC land patterns with verified drop-in compatibility per the PIC12C5xx family datasheet.
Recommended
Sensor Signal Conditioning and Timing
The PIC12C508T-04/SM fits sensor interface modules that need signal conditioning, debouncing, and time-domain processing. Its 8-bit timer with 8-bit prescaler produces precise intervals for sampling thermistors, photodiodes, and simple switch inputs. The 6 I/O pins are sufficient to interface with one analog sensor via an external RC time constant, drive a relay or MOSFET, and communicate status via LED or UART bit-banging. With 25 bytes of RAM, the device can implement moving-average filtering and threshold detection. Compared to pure analog designs, this part enables calibration in firmware rather than via hardware trim.
Recommended
Battery-Powered Devices
The PIC12C508T-04/SM operates effectively in battery-powered applications due to its CMOS design, 2.5 V to 5.5 V supply range (matching 2x AA / 2x AAA alkaline cells down to end-of-life voltage), and integrated brown-out reset that prevents erratic operation at low battery. Sleep current and active current are low enough for portable products with intermittent duty cycles - typical applications include wireless sensor transmitters, BLE beacon drivers (companion to radio), and asset-tracking tags. The OTP memory and SOIJ package support miniaturized form factors required by wearables and IoT edge nodes.
Recommended
Recommended Products Summary
Engineering reference data for PIC12C508T-04/SM — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC12C508-04/SM | PIC12C508T-04I/SM | PIC12C508A-04/SM | PIC12F508-I/SN |
|---|---|---|---|---|---|
| Package | 8-SOIJ | 8-SOIJ (tube) | 8-SOIJ (tape & reel) | 8-SOIJ (tube) | 8-SOIC |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 768 B OTP | 768 B OTP | 768 B OTP | 768 B OTP | 768 B Flash |
| Max Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Operating Voltage | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V |
| Temperature Grade | Commercial 0C to +70C | Commercial 0C to +70C | Industrial -40C to +85C | Commercial 0C to +70C | Industrial -40C to +85C |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash (reprogrammable) |
| I/O Pins | 6 | 6 | 6 | 6 | 6 |
Key Differentiators
- Tape-and-reel packaging for SMT assembly (vs PIC12C508-04/SM)
- Industrial temperature grade variant available (vs PIC12C508-04/SM)
- Flash-based migration path preserves footprint (vs PIC12F508-I/SN)
Design Notes
Decouple VDD (Pin 8) with a 0.1 µF ceramic capacitor placed within 5 mm of the supply pin, with a direct low-inductance trace to VSS (Pin 4). For battery-powered designs, add a bulk capacitor (1 µF to 10 µF) at the VDD node to handle inrush when the MCU wakes from sleep. The integrated brown-out reset triggers at approximately 2.0 V (commercial) or 2.5 V (industrial) to protect OTP memory integrity; do not disable BOR in production code.
Route the ICSP signals (GP0/ICSPDAT and GP1/ICSPCLK) to a programming header with no series resistors; Microchip programmers drive these lines directly. Keep the GP3/MCLR/VPP trace short and away from switching nodes to avoid false resets. For oscillator configurations, place the crystal or resonator within 5 mm of GP5/OSC1 and GP4/OSC2 with a ground guard ring to reduce EMI susceptibility.
GP3 is input-only on the PIC12C508 - configuring it as an output in firmware has no effect and may confuse code review. The OPTION register controls the TMR0 prescaler assignment; verify your timing math accounts for the prescaler, not just TMR0 itself. OTP memory cannot be erased, so any code change after programming requires a new part - validate firmware with PIC12F508 (Flash) before committing to PIC12C508T-04/SM production orders.
Compliance Information
Lifecycle status: NRND (Not Recommended for New Designs) per Microchip product roadmap. RoHS / lead-free / REACH status not confirmed in verified web data - marked as [DATA_NEEDED] for compliance verification. AEC-Q100 automotive qualification is not applicable to this part; for AEC-Q100-grade 8-pin PIC microcontrollers, refer to PIC16F506-I/SL or PIC10F200T-I/OT automotive variants.
