PIC16C558-04/P - 8-bit 4MHz OTP MCU, 3.5KB, 18-PDIP | Microchip
MPN: PIC16C558-04/P ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.98 | $5.98 |
| 10 | $5.62 | $56.20 |
| 100 | $5.1 | $510.00 |
| 500 | $4.65 | $2,325.00 |
| 1,000 | $4.2 | $4,200.00 |
PIC16C558-04/P Overview
An 8-bit microcontroller (MCU) is a single-chip computer integrating a CPU, memory, and peripherals on a single die. 8-bit MCUs sit at the base of the embedded computing hierarchy: MCU -> microcontroller -> embedded processor -> semiconductor. Within the Microchip taxonomy, the PIC16C5x family is the cost-optimized, OTP-based predecessor to the flash-based PIC16F5x/PIC16Fxxx lines, suited to high-volume, fixed-code applications.
Key specifications of the PIC16C558-04/P include a 4 MHz maximum oscillator frequency, 13 GPIO pins arranged across ports RA and RB, an 8-bit timer/counter (TMR0) with an 8-bit programmable prescaler, a wide 3.0 V to 5.5 V operating range, and low-power CMOS construction. The /04 speed suffix indicates the 4 MHz oscillator grade; /20 (20 MHz) variants are also produced. The /P suffix denotes the through-hole PDIP-18 package on a 0.300 inch (7.62 mm) row spacing.
The PIC16C558 uses a 14-bit instruction word with an 8-bit data path. Its RISC CPU keeps the instruction set to 35 single-word opcodes, reducing code density overhead and easing assembly development. Internal peripherals include a watchdog timer, power-on reset, brown-out reset, and an 8-bit prescaler shared between TMR0 and the watchdog.
Typical applications include appliance control, automotive body electronics, sensor interface nodes, simple motor control, industrial monitoring, and low-cost consumer products. The 18-pin count targets mid-sized embedded designs that need more I/O than 14-pin PICs but do not require the larger 20- or 28-pin PIC16C55x siblings.
When designing with the PIC16C558-04/P, note that the OTP program memory cannot be re-programmed in-circuit - firmware must be committed at production time. For prototyping or field-upgradable applications, consider the PIC16F558 or PIC16F57 (flash-based equivalents in the same 18-pin PDIP). An external RC or crystal oscillator between OSC1/OSC2 sets the system clock; a 4 MHz crystal is typical for the /04 grade.
This page synthesizes distributor pricing from Mouser and DigiKey, drop-in and cross-package alternatives drawn from Microchip's compatibility charts, and design notes grounded in the PIC16C55x datasheet - information not consolidated on any single manufacturer or distributor page.
Drop-in alternatives for PIC16C558-04/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 PIC16C558-04/P (same form factor and footprint) — differing in Program Memory Size, Package, Program Memory Type, Timers, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C554-04/P
✅ Drop-In✓ In Stock
$2.85 / Unit
View Datasheet →PIC16C54C-04/P
✅ Drop-In✓ In Stock
$1.71 / Unit
View Datasheet →PIC16C54-04/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C554-04I/P
✅ Drop-In✓ In Stock
$2.2 / Unit
View Datasheet →PIC16F57-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C558-04/P Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit Microcontroller (MCU) |
| Core Architecture | PIC16C RISC (Harvard) |
| Program Memory Type | OTP (One-Time-Programmable) EPROM |
| Program Memory Size | 3.5 KB (2K x 14) |
| Data RAM | 128 bytes |
| Maximum CPU Frequency | 4 MHz |
| Instruction Cycle Time | 200 ns at 4 MHz |
| Instruction Set Size | 35 single-word instructions |
| I/O Pins | 13 |
| Timers | 1 x 8-bit Timer (TMR0) |
| Operating Voltage Range | 3.0 V to 5.5 V |
| Package | 18-PDIP (0.300 inch / 7.62 mm) |
| Watchdog Timer | Yes (with dedicated prescaler) |
| Brown-out Reset | Yes |
| Power-on Reset | Yes |
| Speed Grade Suffix | /04 = 4 MHz oscillator grade |
PIC16C558-04/P Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O port A bit 2 |
| Pin 2 | RA3 — Bidirectional I/O port A bit 3 |
| Pin 3 | RA4/TOCKI — Bidirectional I/O port A bit 4 / Timer0 clock input |
| Pin 4 | MCLR/VPP — Master clear (reset) / Programming voltage input |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — Bidirectional I/O port B bit 0 / External interrupt |
| Pin 7 | RB1 — Bidirectional I/O port B bit 1 |
| Pin 8 | RB2 — Bidirectional I/O port B bit 2 |
| Pin 9 | RB3 — Bidirectional I/O port B bit 3 |
| Pin 10 | RB4 — Bidirectional I/O port B bit 4 |
| Pin 11 | RB5 — Bidirectional I/O port B bit 5 |
| Pin 12 | RB6 — Bidirectional I/O port B bit 6 |
| Pin 13 | RB7 — Bidirectional I/O port B bit 7 |
| Pin 14 | VDD — Positive supply voltage |
| Pin 15 | OSC2/CLKOUT — Oscillator crystal output / Clock output |
| Pin 16 | OSC1/CLKIN — Oscillator crystal input / External clock input |
| Pin 17 | RA0 — Bidirectional I/O port A bit 0 |
| Pin 18 | RA1 — Bidirectional I/O port A bit 1 |
Typical Applications
PIC16C558-04/P is suitable for 6 applications: Appliance Control Boards, Automotive Body Electronics, Industrial Sensor Interface Nodes, Low-Cost Consumer Electronics, Educational and Hobby Projects, Simple Motor and Lighting Controllers.
Appliance Control Boards
The PIC16C558-04/P fits appliance control boards (washing machines, dishwashers, microwave ovens) where fixed firmware drives relays, sensors, and user-interface switches. The 3.5KB OTP program memory holds mid-complexity state machines, the 13 I/O pins directly interface to keypads and LED indicators, and the 3.0V-5.5V range covers both logic-level and 5V relay-coil designs. The 4MHz oscillator grade is sufficient for slow electromechanical control loops, and the CMOS core keeps standby current low for energy-star compliance. Compared to flash parts, OTP programming in production removes the per-unit reprogram cost once code is finalized, lowering the BOM cost in high-volume SKUs.
Recommended
Automotive Body Electronics
The PIC16C558-04/P is a strong fit for automotive body-electronics modules such as seat controllers, mirror adjusters, ambient lighting, and simple sensor nodes. The 13 GPIO pins handle H-bridge enable signals and switch inputs, the 8-bit TMR0 with prescaler services PWM-style delays, and the 3.0V-5.5V supply range tolerates 12V-battery transients after regulation. Per Microchip's product description, the family is well adapted for automotive use. Designers must verify AEC-Q100 qualification status of the specific -04/P part number against the latest Microchip automotive catalog, since the base part may not carry the automotive qualification letter - use automotive-grade siblings for production.
Recommended
Industrial Sensor Interface Nodes
The PIC16C558-04/P suits industrial 4-20 mA loop sensor interfaces, RTD/thermistor readout boards, and remote I/O modules where deterministic 8-bit control and low cost matter more than computational horsepower. The Harvard RISC core gives a fixed 200 ns instruction cycle at 4 MHz, simplifying worst-case timing analysis for safety-critical polling loops. The brown-out reset and watchdog timer, both standard on the part, protect against supply glitches in electrically noisy industrial cabinets. Designers can keep firmware in OTP to lock the calibration permanently, preventing field tampering with sensor scaling coefficients.
Recommended
Low-Cost Consumer Electronics
The PIC16C558-04/P drives low-cost consumer products like toys, remote controls, small kitchen gadgets, and novelty electronics where the BOM cost is the dominant design driver. The 35-instruction RISC set reduces programmer training overhead, and the 3.5KB OTP is plenty for blinky-light sequencers, IR remote decoding, or single-key tone generators. According to the PIC16C55x datasheet, code development can use the same assembler toolchain as larger PIC16 parts, easing team skills transfer. The CMOS implementation reduces quiescent current, allowing battery-powered remotes to last multiple years on a coin cell.
Recommended
Educational and Hobby Projects
The PIC16C558-04/P serves as an affordable teaching platform for embedded-systems courses and hobbyist designs that want to learn RISC assembly on a real, programmable part. The 35-instruction set is small enough to cover in a single lab session, and 18-pin PDIP packages are breadboard-friendly for student prototyping. Universities and makerspaces favor the PDIP form factor for through-hole soldering exercises. However, because the OTP memory cannot be erased, hobby users may prefer the PIC16F57 (Flash) for iteration - the PIC16C558 is best suited to teaching labs that already own an OTP programmer.
Recommended
Simple Motor and Lighting Controllers
The PIC16C558-04/P is well-matched to single-channel DC motor speed controllers, stepper sequencers, and PWM lighting dimmers where the 8-bit TMR0 with prescaler produces adequate PWM resolution at typical switching frequencies. The 13 I/O pins drive H-bridge enable lines, current-sense comparators, and zero-cross detectors for triac-based dimming. The wide 3.0V-5.5V supply range accommodates both 3.3V logic-level and 5V gate-drive designs. According to the PIC16C55x datasheet, the watchdog timer with dedicated prescaler protects against firmware lockup in unattended motor applications, an important safety consideration.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C558-04/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C554-04/P | PIC16C54C-04/P | PIC16C54-04/P | PIC16C554-04I/P | PIC16F57-I/P |
|---|---|---|---|---|---|---|
| Package | 18-PDIP | 18-PDIP - same | 18-PDIP - same | 18-PDIP - same | 18-PDIP - same | 18-PDIP - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 3.5 KB (2K x 14) OTP | 3.5 KB OTP | 512 x 12 OTP | 512 x 12 OTP | 3.5 KB OTP | 2K x 14 Flash |
| Data RAM | 128 B | 128 B | 25 B | 25 B | 128 B | 72 B |
| Max CPU Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz |
| I/O Pins | 13 | 13 | 12 | 12 | 13 | 20 |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash |
| Operating Voltage | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 2.0 V to 5.5 V |
Key Differentiators
- Larger program memory in the PIC16C55x 18-pin PDIP family (vs PIC16C54C-04/P)
- More RAM than smaller PIC16C5x siblings (vs PIC16C54-04/P)
- Lower per-unit cost at high volume vs flash alternatives (vs PIC16F57-I/P)
Design Notes
The OTP program memory cannot be erased or rewritten. Once a PIC16C558-04/P is programmed, firmware changes require a fresh unprogrammed part. For prototype iteration, use a flash-based sibling such as the PIC16F57 (same 18-pin PDIP footprint) and migrate to the PIC16C558 only when the code is finalized. Production programmers must verify the VPP voltage and timing against the PIC16C55x programming specification to avoid silicon damage.
Place the decoupling capacitor (100 nF ceramic) as close as possible to the VDD pin (pin 14) and VSS pin (pin 5), with the ground lead kept short to minimize parasitic inductance. For designs using a crystal oscillator, keep the crystal and its load capacitors physically close to OSC1 (pin 16) and OSC2 (pin 15), and route the MCLR/VPP line away from high-frequency switching nodes to prevent unintended resets during in-circuit programming.
Operating voltage is 3.0 V to 5.5 V (per Verified Web Data). For brown-out protection, configure the BOR module via configuration fuses per the PIC16C55x datasheet so the part resets cleanly during supply droops. The watchdog timer (WDT) has its own dedicated prescaler and runs from the internal RC oscillator - enable it for unattended or safety-critical applications, but disable it during long delays or sleep intervals to avoid spurious resets.
Compliance Information
RoHS, REACH, lead-free, and halogen-free status not explicitly stated in the Verified Web Data. The /P suffix indicates PDIP through-hole package - older PDIP parts may use SnPb lead finish rather than lead-free matte-tin; verify against Microchip's environmental compliance documentation for the specific date code before designing into RoHS-restricted products. AEC-Q100 automotive qualification status not stated for the PIC16C558-04/P in the provided data.
