PIC12C509-04E/P - 8-bit OTP MCU, 1.5KB, 4MHz, PDIP-8 | Microchip
MPN: PIC12C509-04E/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.95 | $1.95 |
| 10 | $1.75 | $17.50 |
| 100 | $1.55 | $155.00 |
| 500 | $1.38 | $690.00 |
| 1,000 | $1.22 | $1,220.00 |
PIC12C509-04E/P Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, non-volatile program memory, working RAM, and peripheral interfaces onto one silicon die. Within the broader taxonomy, the PIC12C509 sits at the bottom of the 8-bit RISC microcontroller hierarchy: microcontroller -> 8-bit MCU -> RISC MCU -> PIC architecture -> Microchip PIC12 sub-family -> PIC12C509 part. PIC12C devices are widely used as glue logic, timers, low-cost controllers, and OTP-based fixed-function modules where flash reprogrammability is not required.
Key specifications of the PIC12C509-04E/P include a 4 MHz maximum operating frequency, a 1 us instruction cycle time (4 MHz oscillator / 4), 1.5 KB OTP program memory organized as 1K x 12 words, 41 bytes of data RAM, six I/O pins with 25 mA source/sink drive capability per pin, four oscillator selections (including the factory-calibrated internal 4 MHz RC), and Power-on Reset (POR). The "E" suffix designates the extended temperature range of -40C to +125C, while the "04" indicates the 4 MHz speed grade.
Architecturally, the PIC12C509 uses Microchip's classic PIC RISC core with a two-stage pipeline and a single accumulator (W register). It supports 33 single-word instructions, has eight special function registers mapped into a small data RAM bank, and features a 5-bit GPIO port shared with the internal oscillator and MCLR functions. A watchdog timer with its own on-chip RC oscillator is optional for safety-critical applications.
Typical applications include low-cost appliance control, sensor interface modules, battery chargers, LED controllers, and replacement of discrete logic in space-constrained designs. The extended temperature range allows use in automotive underhood environments and outdoor industrial equipment. Because the part is OTP rather than Flash, it is best suited to high-volume production where firmware is final and stable, rather than iterative prototyping.
When designing with this device, allocate sufficient decoupling (a 0.1 uF ceramic on VDD close to the pin) and reserve the MCLR/VPP pin for in-circuit programming or tie it to VDD through a 10 kohm resistor for normal operation. Note that the PIC12C509 series has been succeeded by Flash-based PIC10F/PIC12F families for new designs; choose PIC12C509-04E/P only when matching an existing OTP BOM.
This page synthesizes distributor stock data, drop-in alternatives from the PIC12C509 family, and practical design notes not found in the bare datasheet. All pricing reflects market conditions as of 2026-09-14.
Drop-in alternatives for PIC12C509-04E/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 PIC12C509-04E/P (same form factor and footprint) — differing in Operating Temperature, Package, Timers, Core Architecture, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC12C509-04/P
✅ Drop-In✓ In Stock
$1.18 / Unit
View Datasheet →PIC12C509A-04E/P
✅ Drop-In✓ In Stock
$1.1 / Unit
View Datasheet →PIC12C509A-04/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12F508-I/P
✅ Drop-In✓ In Stock
$0.5 / Unit
View Datasheet →PIC10F200-I/P
✅ Drop-In✓ In Stock
$0.28 / Unit
View Datasheet →PIC10F322-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12C509-04E/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC |
| Program Memory Type | OTP (One-Time-Programmable) |
| Program Memory Size | 1.5 KB (1K x 12 words) |
| Data RAM | 41 bytes |
| Data EEPROM | None (OTP only) |
| Maximum CPU Frequency | 4 MHz |
| Instruction Cycle Time | 1 us @ 4 MHz |
| I/O Pins | 6 |
| I/O Sink/Source Current | 25 mA per pin |
| Supply Voltage (VDD) | 2.5 V to 5.5 V |
| Oscillator Options | 4 selections (internal RC, external RC, XT, LP) |
| Internal RC Oscillator | 4 MHz factory-calibrated |
| Operating Temperature | -40C to +125C (extended grade, "E") |
| Package Type | PDIP-8 (0.300 inch / 7.62 mm) |
| Mounting Type | Through-Hole (DIP) |
| MSL Level | 1 (unlimited floor life) |
PIC12C509-04E/P Pin Configuration
| Pin 1 | VDD — Positive supply voltage (2.5V to 5.5V) |
| Pin 2 | OSC1/CLKIN — Oscillator input or external clock in |
| Pin 3 | OSC2/CLKOUT — Oscillator output or clock out |
| Pin 4 | MCLR/VPP — Master Clear reset (active low) or programming voltage input |
| Pin 5 | VSS — Ground reference |
| Pin 6 | GP0 — Bidirectional I/O pin 0 |
| Pin 7 | GP1 — Bidirectional I/O pin 1 |
| Pin 8 | GP2/T0CKI — Bidirectional I/O pin 2 / Timer0 clock input |
Typical Applications
PIC12C509-04E/P is suitable for 6 applications: Appliance Control Boards, LED Lighting Controllers, Battery-Powered Sensor Nodes, Automotive Underhood Modules, Industrial Timer and Counter Modules, Replacement of Discrete Logic (Glue Logic Controllers).
Appliance Control Boards
The PIC12C509-04E/P's 6 GPIO pins with 25 mA source/sink drive, 1.5 KB OTP program memory, and extended -40C to +125C temperature range make it a strong fit for low-cost appliance controllers in washing machines, dishwashers, and microwave ovens. Its 33 single-word RISC instructions and 1 us cycle time at 4 MHz deliver roughly 1 MIPS - enough to handle button scanning, triac drive, LED indication, and relay sequencing. The OTP memory is ideal because appliance firmware is final at production and OTP prevents unauthorized field re-flashing. Compared with a PIC10F200, the PIC12C509-04E/P provides more code space for state-machine logic without requiring PCB layout changes.
Recommended
LED Lighting Controllers
RGB LED controllers and decorative lighting strips benefit from the PIC12C509-04E/P's 25 mA I/O drive (sufficient to directly drive small MOSFET gates or low-current LED strings via resistors) and its compact 8-pin PDIP footprint. The internal 4 MHz RC oscillator eliminates two external crystal pins, freeing GPIOs for PWM channels. At 4 MHz, software PWM can achieve refresh rates well above 100 Hz to avoid visible flicker. The extended-temperature grade supports outdoor LED installations. For very low standby power, the PIC12C509-04E/P's sleep mode with watchdog wake-up keeps quiescent current in the microamp range.
Recommended
Battery-Powered Sensor Nodes
Simple battery-powered sensor transmitters - such as remote temperature probes, soil moisture sensors, and door/window contact sensors - are well served by the PIC12C509-04E/P's wide 2.5V-5.5V supply range, low sleep current, and tiny 8-pin PDIP package. A 1.5 KB OTP program comfortably fits typical sensor-encoding routines, and the internal 4 MHz RC oscillator removes the need for a power-hungry external crystal. The extended temperature range supports outdoor and automotive environments. Engineers migrating from the OTP PIC12C509 to a Flash-based PIC for development can drop in a PIC12F508-I/P on the same PCB and reuse the firmware with minor tweaks.
Recommended
Automotive Underhood Modules
The PIC12C509-04E/P's "E" extended temperature rating (-40C to +125C) qualifies it for automotive underhood environments where ambient temperatures regularly exceed 100C. Combined with 25 mA I/O drive capable of switching 12V automotive loads through small FETs, the part can run simple ECU subfunctions like fan control, sensor signal conditioning, or wiper timing. OTP prevents accidental firmware modification under EMI stress. When designing underhood modules, place a TVS diode on VDD and an RC filter on MCLR to handle automotive transients per ISO 7637. Production modules typically ship with PIC12C509A-04E/P for the silicon revision improvement.
Recommended
Industrial Timer and Counter Modules
Industrial DIN-rail timer modules, machine-hour counters, and process-interval controllers fit naturally with the PIC12C509-04E/P's built-in Timer0 module, watchdog timer, and Power-on Reset. The 4 MHz internal RC is sufficient for timing accurate to within a few percent, while the OTP memory locks in calibrated timing constants. Six I/O pins are adequate to drive a 4-digit 7-segment display via a serial shift register. The PDIP-8 through-hole package is preferred for industrial wiring harnesses where leaded packages survive vibration better than SMD. The -40C to +125C extended range covers factory-floor temperature extremes.
Recommended
Replacement of Discrete Logic (Glue Logic Controllers)
The PIC12C509-04E/P can replace a board full of 4000/7400-series CMOS logic - such as a sequence of monostables, gates, counters, and shift registers - with a single 8-pin chip. At $1.55 in 100-piece quantities, it is often cheaper than the discrete logic it replaces and dramatically reduces PCB area. With 1.5 KB OTP and 33 instructions, simple state machines of 50-200 states fit comfortably. A typical application is a custom debounce-and-sequence circuit for a kiosk push-button array. The PIC12C509-04E/P is preferred over a CPLD here because of its lower unit cost and lower quiescent current.
Recommended
Recommended Products Summary
Engineering reference data for PIC12C509-04E/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC12C509-04/P | PIC12C509A-04E/P | PIC12F508-I/P |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | PDIP-8 | PDIP-8 | PDIP-8 | PDIP-8 |
| Program Memory Type | OTP 1.5 KB | OTP 1.5 KB | OTP 1.5 KB | Flash 768 B |
| Data RAM | 41 bytes | 41 bytes | 41 bytes | 25 bytes |
| Maximum CPU Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Operating Temperature | -40C to +125C (E grade) | 0C to +70C | -40C to +125C (E grade) | -40C to +85C (I grade) |
| I/O Pins | 6 | 6 | 6 | 6 |
| Reprogrammable In-System | No (OTP only) | No (OTP only) | No (OTP only) | Yes (Flash) |
| Approx. 100-piece Price | $1.55 | $1.45 | $1.60 | $1.10 |
Key Differentiators
- Extended -40C to +125C temperature grade (vs PIC12C509-04/P)
- Improved silicon revision for production (vs PIC12C509A-04E/P)
- Reprogrammable Flash vs OTP (vs PIC12F508-I/P)
Design Notes
Place a 0.1 uF ceramic decoupling capacitor on VDD (pin 1) within 3 mm of the package, with the trace to the cap kept short and the ground return directly to pin 5 (VSS). For battery applications, add a bulk 10 uF tantalum or aluminum polymer cap on the same rail. The PIC12C509-04E/P can operate down to 2.5 V, but brown-out detection is not built in, so an external voltage supervisor (e.g. MCP100) is recommended if VDD can sag below 2.5 V under load.
If using the internal 4 MHz RC oscillator, leave OSC1 (pin 2) and OSC2 (pin 3) as no-connects or tie OSC1 to VSS through 100 kohm if not used. For an external crystal or resonator, keep traces short (<5 mm), place a ground guard ring around the oscillator, and ground the case of the resonator to reduce EMI pickup. The PDIP-8 through-hole pads are forgiving for hand prototyping but should be pulled to the top copper pour with thermal relief spokes for wave-solder reliability.
PIC12C509 is OTP only - once programmed it cannot be erased or rewritten. Always program samples in a development socket first and verify with a known-good PIC12F508-I/P before committing to the OTP part for production. The MCLR/VPP pin (pin 4) must NOT be left floating; tie to VDD through a 10 kohm resistor for normal operation or to the ICD programmer during development. Pins GP3, GP4, GP5 listed in some datasheet tables are NOT available on the 8-pin variant - they only exist on the PIC12C509 in larger 18-pin and 20-pin packages.
Compliance Information
RoHS/REACH compliance status for the leaded PDIP-8 variant was not explicitly stated in the verified web data; marked as [DATA_NEEDED] in the specs array. The PIC12C509 family is not AEC-Q100 qualified; for automotive underhood designs, perform additional component-level qualification per the target OEM.
