PIC12C509-04/P - 8-Bit 4MHz OTP MCU 1.5KB | Microchip
MPN: PIC12C509-04/P β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.95 | $1.95 |
| 10 | $1.78 | $17.80 |
| 100 | $1.55 | $155.00 |
| 500 | $1.32 | $660.00 |
| 1,000 | $1.18 | $1,180.00 |
PIC12C509-04/P Overview
An 8-bit microcontroller is a single-chip computer that processes data in 8-bit-wide chunks using a Harvard or modified-Harvard architecture; in the Microchip taxonomy it sits under the PIC family, which is itself a sub-family of microcontrollers, embedded controllers, and ultimately standard ICs. OTP variants are programmed once by the user or contract manufacturer, in contrast to flash-based PICs that allow field re-programming, which makes them attractive for low-cost, high-volume, fixed-function applications.
Key features include a RISC core with 33 single-cycle instructions, a programmable 4 MHz internal/external oscillator option, a watchdog timer with its own on-chip RC oscillator for reliable recovery, power-saving Sleep mode, and a wide operating voltage range of 2.5 V to 5.5 V. The 8-pin footprint gives 6 usable I/O lines plus VDD and VSS, with each I/O capable of sourcing up to 25 mA for direct LED drive. The device is qualified for the standard 0 Β°C to +70 Β°C commercial temperature range (the -04 speed grade and /P PDIP suffix) and is RoHS-compliant.
Typical applications span low-cost consumer appliances, hobby/educational projects, simple sensor interfaces, and replacement of discrete logic. Designers should leave enough PCB area for the through-leads and apply decoupling capacitors within 5 mm of VDD/VSS; the MCLR pin must be tied high through a resistor for normal operation and pulled low only for in-circuit serial programming.
Drop-in alternatives for PIC12C509-04/P β 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 PIC12C509-04/P (same form factor and footprint) β differing in Package, Program Memory Size, Program Memory Type, Comparator, Core Architecture.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC12C509A-04/P
β Drop-Inπ Reference alternative (not in catalog)
PIC12C508A-04/P
β Drop-Inβ In Stock
$0.95 / Unit
View Datasheet βPIC12F509-I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC12F508-I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC12C508-04/P
β Drop-Inβ In Stock
$1.62 / Unit
View Datasheet βPIC12C509-04/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC |
| Core Sub-family | Baseline PIC12C |
| Program Memory Type | OTP (One-Time Programmable) EPROM |
| Program Memory Size | 1.5 KB (1K x 12) |
| Data RAM | 41 bytes |
| Data EEPROM | Not present |
| Maximum CPU Clock | 4 MHz |
| Instruction Cycle Time | 200 ns (4 MHz, 1:1 clock ratio for /04 variant) |
| Operating Voltage Range | 2.5 V to 5.5 V |
| I/O Pins | 6 (of 8 package pins; 2 are VDD/VSS) |
| I/O Sink/Source Current | 25 mA per pin |
| Timers | 1 x 8-bit Timer0 with watchdog |
| Watchdog Timer | Yes, dedicated on-chip RC oscillator |
| ADC | Not present |
| Comparator | Not present |
| ICSP (In-Circuit Serial Programming) | Yes (2-wire) |
| Package | 8-pin PDIP (300 mil) |
| Mounting Type | Through-Hole |
| Operating Temperature Range | 0 Β°C to +70 Β°C (commercial) |
| RoHS Status | Compliant |
PIC12C509-04/P Pin Configuration
| Pin 1 | GP5/OSC1/CLKIN β GPIO GP5 / external oscillator input / external clock input |
| Pin 2 | GP4/OSC2/CLKOUT β GPIO GP4 / external oscillator output / clock output |
| Pin 3 | GP3/MCLR/VPP β GPIO GP3 / Master Clear reset (active low) / programming voltage |
| Pin 4 | GP2/T0CKI β GPIO GP2 / Timer0 external clock input |
| Pin 5 | GP1 β GPIO GP1 |
| Pin 6 | GP0 β GPIO GP0 |
| Pin 7 | VSS β Ground reference |
| Pin 8 | VDD β Positive supply (2.5 V to 5.5 V) |
Typical Applications
PIC12C509-04/P is suitable for 6 applications: Low-Cost Consumer Appliance Controller, Educational Microcontroller Learning Platform, Discrete-Logic Replacement / Glue Controller, Simple Sensor Interface / Signal Conditioner, Automotive Interior Lighting Module (Pre-CAN Era Style), Battery-Operated IoT Edge Node (Sleep-Duty Cycle).
Low-Cost Consumer Appliance Controller
The PIC12C509-04/P fits small household appliances (toasters, fans, simple timers) because of its 1.5 KB OTP program memory, 6 GPIO pins (sufficient for relay, button, LED, and buzzer), and 25 mA per-pin drive that can source LEDs without a driver. With a 4 MHz internal RC plus external crystal option, the device runs a fixed state-machine cleanly. At 2.5-5.5 V it operates directly from 3.3 V or 5 V rails, while OTP keeps BOM cost low in mass production. The 8-pin PDIP through-hole package is friendly to hand-soldered prototypes and small-batch runs.
Recommended
Educational Microcontroller Learning Platform
The PIC12C509-04/P is a popular microcontroller for university and hobbyist courses because of its simple baseline RISC architecture (33 instructions), small 1.5 KB memory that forces disciplined coding, and 8-pin PDIP package that drops into a breadboard or DIP socket. Students learn timer interrupts, watchdog reset, and Sleep-mode power saving on a real production silicon without the complexity of peripherals. The /04 4 MHz grade provides a 200 ns instruction cycle, easy to trace by hand. The MCLR pin supports 2-wire ICSP, allowing instructors to demonstrate programming workflows.
Recommended
Discrete-Logic Replacement / Glue Controller
Replacing 4-6 discrete 74HC gates with one PIC12C509-04/P shrinks PCB area and gives designers a programmable state machine instead of hard-wired logic. With 6 GPIO and 4 MHz CPU, it can scan a 4-key keypad, drive a small LED, and toggle a relay in well under 1 ms. The 41-byte RAM is enough for a lookup-table decoder. OTP memory and 25 mA per-pin drive let it switch relays or low-side MOSFETs directly. The 8-pin PDIP footprint and 0-70 Β°C commercial range suit industrial control panels and instrumentation front-ends.
Recommended
Simple Sensor Interface / Signal Conditioner
The PIC12C509-04/P can serve as a low-cost sensor interface (RTD, thermistor, or humidity sensor digitizer) where the on-chip Timer0 measures RC charge time to within 1% and the 4 MHz CPU computes linearization. Six GPIO is sufficient for sensor power-gate, sense input, alert LED, and 1-wire output. The 2.5 V minimum supply lets it run directly from a single Li coin cell. The /04 speed grade ensures deterministic 200 ns cycle timing for sensor read. 41 bytes RAM easily holds calibration constants.
Recommended
Automotive Interior Lighting Module (Pre-CAN Era Style)
For low-current automotive interior lighting (door-step lamps, vanity LEDs, courtesy lights), the PIC12C509-04/P provides 6 GPIO that can PWM multiple LEDs through MOSFET drivers at 4 MHz. 25 mA per-pin source lets it drive small LEDs directly, and 1.5 KB of code supports smooth fade-in/fade-out ramps. Note that this part lacks AEC-Q100 qualification; for new automotive designs Microchip recommends PIC16F1xxx AEC-Q100 qualified parts. Use the /04 grade's deterministic 200 ns timing for repeatable PWM periods.
Recommended
Battery-Operated IoT Edge Node (Sleep-Duty Cycle)
In battery-powered sensor edge nodes, the PIC12C509-04/P's Sleep mode (current at the Β΅A level) combined with watchdog wakeup yields years of life on a CR2032. The 4 MHz /04 clock provides fast wake-and-process cycles (200 ns per instruction) so the CPU spends most of its time asleep. 41 bytes RAM and 6 GPIO are enough for a single sensor read and an interrupt-driven wake. The 2.5 V minimum supply operates directly from a depleted 3 V coin cell. OTP keeps BOM cost minimal in fixed-function sensor pucks.
Recommended
Recommended Products Summary
Engineering reference data for PIC12C509-04/P β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC12C509A-04/P | PIC12C508A-04/P | PIC12F509-I/P | PIC12F508-I/P | PIC12C508-04/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 8-pin PDIP | 8-pin PDIP | 8-pin PDIP | 8-pin PDIP | 8-pin PDIP | 8-pin PDIP |
| Program Memory | 1.5 KB OTP | 1.5 KB OTP | 768 B OTP | 1.5 KB Flash | 768 B Flash | 768 B OTP |
| Data RAM | 41 bytes | 41 bytes | 25 bytes | 41 bytes | 25 bytes | 25 bytes |
| Maximum CPU Clock | 4 MHz | 4 MHz | 4 MHz | 20 MHz | 20 MHz | 4 MHz |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | Flash | Flash | OTP EPROM |
| I/O Pins | 6 | 6 | 6 | 6 | 6 | 6 |
| Operating Voltage | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.5 V to 5.5 V |
Key Differentiators
- Largest OTP program memory in the 8-pin baseline PIC12 family (vs PIC12C508A-04/P)
- OTP memory is ideal for high-volume fixed-function designs (vs PIC12F509-I/P)
- 4 MHz speed grade is fast enough for tight control loops (vs PIC12C508-04/P)
Design Notes
Place a 100 nF decoupling capacitor as close as possible to the VDD pin (pin 8) of the PIC12C509-04/P, ideally within 5 mm. For designs switching relays or LEDs, add a 10 Β΅F bulk capacitor near the regulator. The device is fully static, so the internal state is preserved even with the clock stopped - this allows aggressive Sleep-mode duty cycling to reach Β΅A-level average current on battery-powered designs.
When using an external crystal or resonator, place it within 5-10 mm of the OSC1/OSC2 pins (pins 1-2) and guard the traces with a ground ring to reduce EMI pickup. For ICSP programming, dedicate the MCLR/VPP pin (pin 3) to a 10 kΞ© pull-up resistor and expose it (along with GP0/GP1) on a programming header. Do not place a series capacitor on MCLR in production - leave it accessible for the programmer.
The PIC12C509-04/P uses OTP EPROM, so firmware cannot be revised once programmed. Lock the code-protect bit only after final firmware is verified, because a code-protected OTP part cannot be re-programmed to recover access. The 41-byte RAM is shared with the 2-level hardware stack, so reserve at least 4 bytes for stack frames. Finally, do not drive any GPIO pin above VDD or below VSS - the absolute maximum rating is -0.3 V to +6.0 V, but exceeding VDD by even 0.5 V will forward-bias internal ESD diodes and inject current into the supply rail.
Keep the MCLR trace short and direct; long MCLR traces pick up noise and cause spurious resets. If the design is in an electrically noisy environment (near a motor or relay), add a 100 nF ceramic in parallel with the MCLR pull-up. For multi-ICSP chains (production programming of multiple boards), include a 4.7 kΞ© isolation resistor on the data line so one board's programmer does not back-drive another.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified - not suitable for new automotive designs. Lead-free PDIP package.
