PIC12C508A-04/P - 8-bit 4MHz OTP MCU 768B | Microchip | DIP-8
MPN: PIC12C508A-04/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.6 | $1.60 |
| 10 | $1.4 | $14.00 |
| 100 | $1.18 | $118.00 |
| 500 | $1.05 | $525.00 |
| 1,000 | $0.95 | $950.00 |
PIC12C508A-04/P Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, program memory, data memory, and integrated peripherals. The PIC12C508A belongs to the 8-bit microcontroller category, which uses an 8-bit data path. Within the broader hierarchy, it sits as: PIC12C508A -> PIC12C5xx family -> PIC architecture -> 8-bit MCU -> microcontroller -> embedded computing IC. This MCU variant uses CMOS process technology with EPROM/OTP-based program storage, distinguishing it from Flash-based 8-bit MCUs that allow multiple reprogram cycles.
Key features include 33 single-word/single-cycle instructions, 1 microsecond instruction execution time at 4MHz, 6 general-purpose I/O pins, a hardware 8-bit timer (TMR0) with 8-bit programmable prescaler, watchdog timer with on-chip RC oscillator, power-on reset, and in-circuit serial programming (ICSP) capability. The device also offers 4 oscillator options: RC, LP, XT, and HS, providing flexibility across low-power and high-speed applications. Power consumption is typically under 2 mA active at 5V/4MHz and below 1 microamp in sleep mode.
The PIC12C508A-04/P employs a Harvard RISC architecture with separate program and data buses, and 12-bit wide instructions yielding 2:1 code compression over comparable 8-bit CISC controllers. The -04 speed suffix designates 4MHz operation, and the /P suffix indicates a PDIP-8 (300 mil) through-hole package. Operating voltage spans 2.5V to 5.5V across commercial and industrial temperature ranges (0C to +70C for commercial, -40C to +85C for industrial). The OTP nature of program memory means firmware is programmed once via Microchip's MPLAB ecosystem and cannot be field-updated.
Typical applications include appliance control modules, LED driver controllers, simple sensor interfaces, low-end consumer electronics, and battery-powered devices. Its small 8-pin footprint and 33-instruction RISC core suit designs where PCB real estate is constrained and code volume is below 768 bytes. The device is widely deployed in cost-sensitive mass-production units.
Design consideration: Because the program memory is OTP, a burned device cannot be reprogrammed, so engineers should always verify code with a development-friendly equivalent (such as the PIC12F508 with Flash memory) before committing to OTP volume production. The /P 8-pin PDIP variant is also ideal for through-hole prototyping and hobby projects.
This page consolidates distributor pricing, pin-compatible drop-in alternatives, and practical design considerations that go beyond the manufacturer datasheet summary.
Drop-in alternatives for PIC12C508A-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 PIC12C508A-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:
PIC12C508A-04I/P
✅ Drop-In✓ In Stock
$0.81 / Unit
View Datasheet →PIC12C508-04/P
✅ Drop-In✓ In Stock
$1.62 / Unit
View Datasheet →PIC12F508-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12C508A-04E/P
✅ Drop-In✓ In Stock
$1.74 / Unit
View Datasheet →PIC12C509A-04/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12C508A-04/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Program Memory Type | OTP (One-Time-Programmable) |
| Program Memory Size | 768 B (512 x 12 words) |
| Data RAM | 25 B |
| CPU Speed | 4 MHz (1 us instruction cycle) |
| Instruction Set | 33 single-word/single-cycle instructions |
| General-Purpose I/O | 6 pins |
| Timers | 1 x 8-bit TMR0 with programmable prescaler |
| Watchdog Timer | Yes (with on-chip RC oscillator) |
| Oscillator Modes | RC, LP, XT, HS (4 options) |
| In-Circuit Serial Programming (ICSP) | Yes |
| Operating Voltage | 2.5 V to 5.5 V |
| Supply Current (active, 4 MHz/5V) | < 2 mA typical |
| Supply Current (sleep) | < 1 uA typical |
| Operating Temperature | 0C to +70C (commercial) |
| Package | PDIP-8 (300 mil) |
| Mounting Type | Through-Hole |
| RoHS Status | Compliant |
PIC12C508A-04/P Pin Configuration
| Pin 1 | VSS — Ground reference |
| Pin 2 | T0CKI/GP5 — Timer0 clock input / general-purpose I/O pin 5 |
| Pin 3 | GP4/OSC2 — General-purpose I/O pin 4 / oscillator output |
| Pin 4 | GP3/MCLR — General-purpose I/O pin 3 / Master Clear (reset) input |
| Pin 5 | GP2/OSC1 — General-purpose I/O pin 2 / oscillator input |
| Pin 6 | GP1 — General-purpose I/O pin 1 |
| Pin 7 | GP0 — General-purpose I/O pin 0 |
| Pin 8 | VDD — Positive supply voltage (2.5V to 5.5V) |
Typical Applications
PIC12C508A-04/P is suitable for 6 applications: Appliance Control Modules, LED Driver Controllers, Simple Sensor Interface Hubs, Low-End Consumer Electronics, Battery-Powered Devices, Automotive Interior Accessories.
Appliance Control Modules
The PIC12C508A-04/P fits appliance control modules such as microwave oven user interfaces, washing-machine front panels, and dishwasher timer boards, where 6 general-purpose I/O pins are sufficient to drive a 7-segment display, scan a 4x3 keypad, and control a relay or triac. Its 4 MHz CPU provides enough bandwidth for keypad debounce, relay timing, and basic state-machine logic without external components. Compared with discrete logic, the MCU's 33 single-cycle instructions collapse what would be a dozen gates into a single 1.60 USD part, and the 8-pin PDIP footprint drops directly onto legacy through-hole PCBs used in white goods. The 25-byte RAM accommodates debounce counters and mode flags; the 768-byte OTP memory holds the full appliance state machine.
Recommended
LED Driver Controllers
The PIC12C508A-04/P serves as a low-cost LED driver controller in decorative lighting, signage, and indicator-strip applications, where 6 I/O pins can drive multiple LED channels via PWM generated in software. Its 4 MHz core allows software PWM at refresh rates above 100 Hz with 8-bit resolution, sufficient to avoid visible flicker in dimming applications. The MCU's 2.5-5.5V operating range matches typical LED-rail voltages, and the less-than-1 uA sleep current enables battery-backed LED nightlights that idle for months. Compared with dedicated LED-driver ICs, the PIC12C508A-04/P adds general-purpose programmability, letting one MCU control RGB color mix and blink patterns across multiple channels.
Recommended
Simple Sensor Interface Hubs
The PIC12C508A-04/P is well-suited as a simple sensor interface hub for thermistor reading, photoresistor light-level sampling, and mechanical-switch polling, where a single 8-bit ADC channel and a few digital I/O lines replace dedicated sensor-conditioning circuits. Its 8-bit TMR0 with programmable prescaler provides accurate timing for periodic sensor reads at intervals from microseconds to seconds. The on-chip watchdog timer ensures the sensor-reading firmware recovers from glitches in electrically noisy industrial environments. Compared with a dedicated sensor-interface ASIC, the PIC12C508A-04/P offers calibration flexibility through software, allowing one part number to serve multiple product variants by changing the firmware stored in 768 bytes of OTP.
Recommended
Low-End Consumer Electronics
The PIC12C508A-04/P is deployed in low-end consumer electronics such as remote-control key fobs, novelty toys, and small kitchen gadgets, where 6 I/O pins and 768 bytes of program memory are sufficient to handle button inputs, IR transmission, and basic sound or motion effects. Its 1 us instruction cycle at 4 MHz easily decodes RC5 or NEC IR protocols in software without an external decoder IC. The PDIP-8 package supports both automated through-hole assembly and hand-prototyping in maker communities, lowering entry barriers for hobby products. The MCU's 2.5-5.5V operating range and under-2-mA active current align with 3V coin-cell and 5V USB-supplied consumer products.
Recommended
Battery-Powered Devices
The PIC12C508A-04/P is ideal for battery-powered devices such as wireless doorbell transmitters, smoke-detector test circuits, and personal health monitors, where the sub-1 uA sleep current extends battery life into the multi-year range. The MCU wakes from sleep on watchdog overflow or external interrupt, executes a brief measurement or transmit routine, and returns to sleep, all within a few hundred microseconds of active time per duty cycle. Its 2.5V minimum operating voltage allows operation from two nearly-depleted AA cells. Compared with discrete low-power timer circuits, the PIC12C508A-04/P replaces 4-6 analog components with a single programmable part that adapts to changing product requirements through software updates prior to OTP programming.
Recommended
Automotive Interior Accessories
The PIC12C508A-04/P serves in non-safety automotive interior accessories such as ambient lighting controllers, USB-charger status indicators, and seat-occupancy indicator LEDs, where 6 I/O pins drive a small number of outputs and the commercial 0C to +70C temperature range is sufficient for cabin environments. Its 33-instruction RISC core handles LIN-like bit-banged communication or simple PWM dimming of interior LED strips. The PDIP-8 package suits through-hole assemblies in aftermarket accessory modules. The 768-byte OTP memory holds the full accessory state machine, and the sub-1 uA sleep current prevents vehicle battery drain when the car is parked for weeks.
Recommended
Recommended Products Summary
Engineering reference data for PIC12C508A-04/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC12C508A-04I/P | PIC12C508-04/P | PIC12F508-I/P | PIC12C508A-04E/P | PIC12C509A-04/P |
|---|---|---|---|---|---|---|
| Package | PDIP-8 | PDIP-8 (same) | PDIP-8 (same) | PDIP-8 (same) | PDIP-8 (same) | PDIP-8 (same) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 768 B OTP | 768 B OTP | 768 B OTP | 768 B Flash | 768 B OTP | 1.5 KB OTP |
| Data RAM | 25 B | 25 B | 25 B | 25 B | 25 B | 41 B |
| Max CPU Speed | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Memory Type | OTP | OTP | OTP | Flash | OTP | OTP |
| I/O Pins | 6 | 6 | 6 | 6 | 6 | 6 |
| Operating Temperature | 0C to +70C | -40C to +85C | 0C to +70C | -40C to +85C | -40C to +125C | 0C to +70C |
| Reprogrammable | No (OTP) | No (OTP) | No (OTP) | Yes (Flash) | No (OTP) | No (OTP) |
Key Differentiators
- Industry-standard 8-pin PDIP through-hole package for hand-prototyping and legacy designs (vs PIC12C508A-04/SM (SOIC-8 surface mount))
- OTP memory for lowest per-unit cost at high volume (vs PIC12F508-I/P (Flash-based equivalent))
- RISC architecture with 33 single-cycle instructions simplifies firmware development (vs Discrete logic or 8051-based 8-bit MCUs)
Design Notes
Because the PIC12C508A-04/P uses OTP program memory, it cannot be reprogrammed once written. Engineers must fully validate firmware on a Flash-based equivalent (such as the PIC12F508-I/P, same PDIP-8 footprint) before committing to OTP volume production. Programming is performed via Microchip's MPLAB X IDE and ICD or PICkit programmers using the ICSP interface (GP0/GP1/GP3 pins). Always order at least 5-10% extra OTP units for engineering rework and field-replacement inventory.
Place a 100 nF decoupling capacitor as close as possible to the VDD pin (pin 8) to suppress digital switching noise, and a 10 uF bulk capacitor on the same supply rail if the PCB is shared with relays or other noisy loads. The MCLR pin (pin 4) requires a 10 kohm pull-up to VDD; a 100 nF capacitor from MCLR to ground is optional but recommended for noisy environments. The OSC1/OSC2 pins should be routed with short traces to the crystal or resonator to reduce EMI and oscillator startup issues.
For battery-powered designs, leverage the PIC12C508A-04/P's sub-1 uA sleep current by entering sleep mode (SLEEP instruction) and waking on watchdog overflow (WDT) or external interrupt (GP0/GP1/GP3). Average current consumption can drop below 10 uA in typical 1% duty-cycle sensor-reading applications, enabling 2-5 year battery life from a single CR2032 coin cell. Estimated: 10 uA average from 1% active duty cycle (2 mA active / 100) + 1 uA sleep current. Use the internal 4 MHz RC oscillator to avoid the additional current draw of an external crystal in cost-sensitive applications.
Keep the ICSP programming lines (GP0/GP1/GP3) accessible on the PCB via a 3-pin or 5-pin header for in-circuit programming during production. If the design uses GP0/GP1/GP3 as outputs, ensure they can be temporarily tri-stated during programming by adding 10 kohm series resistors or jumpers. The MCLR pull-up should remain present even when the ICSP header is disconnected, otherwise the MCU will not run. Avoid routing high-frequency or high-current signals adjacent to OSC1/OSC2 to prevent oscillator drift.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified; for AEC-Q100 automotive applications consider PIC12F508-E/P or PIC16F family. Lead-free PDIP-8 package, halogen-free per Microchip material declaration.
