PIC16LC558-04I/P - 4MHz 8-Bit OTP MCU, 3.5KB, 18-PDIP | Microchip
MPN: PIC16LC558-04I/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.55 | $25.50 |
| 100 | $2.21 | $221.00 |
| 500 | $1.94 | $970.00 |
| 1,000 | $1.73 | $1,730.00 |
PIC16LC558-04I/P Overview
An 8-bit microcontroller is a single-chip computer containing a CPU, program memory, RAM, and peripheral I/O on one die. The PIC16C5X baseline family uses a RISC architecture with a 33-instruction set, two-stack hardware, and OTP ROM for cost-sensitive embedded applications. LC variants denote the low-power CMOS process node, while the 16C5X core is one of the most widely deployed legacy 8-bit architectures in industrial control, white goods, and consumer devices.
Key features of the PIC16LC558-04I/P include a maximum instruction cycle of 250 ns at 4 MHz, integrated watchdog timer with on-chip RC oscillator, power-on reset, and up to 13 bidirectional I/O pins with programmable pull-ups. The device supports in-circuit serial programming via the RB6/RB7 pins on compatible parts and includes a hardware timer/counter (TMR0) with an 8-bit prescaler. Sleep mode current drops to a few microamps, enabling battery-friendly standby behavior in always-on systems.
The PIC16LC558 uses Microchip's classic baseline architecture, employing a 14-bit instruction word and separate program/data buses (Harvard) so that the fetch and execute phases can be pipelined. The ALU operates on 8-bit data with carry/borrow and bit-manipulation primitives that make single-bit I/O control concise in C or assembly. The LC process reduces dynamic power consumption compared with the original EPROM-based 16C5X parts, making this MCU a popular replacement in industrial installations where newer flash-based PICs are not form-fit compatible.
Typical applications include legacy industrial controllers, appliance user-interface boards, motor-driver slave controllers, simple sensor-front-end signal conditioning, and remote-control transmitter/receiver pairings. The 18-pin PDIP footprint also makes the part well suited to through-hole hobby and educational platforms, breadboard prototyping, and equipment retrofits where a surface-mount part cannot be used.
When designing with this device, note that OTP memory cannot be re-programmed, so firmware must be fully validated before final programming. Use decoupling capacitors of 0.1 µF close to VDD/VSS, follow the datasheet's oscillator layout guidelines, and respect the maximum I/O sink/source ratings of 25 mA per pin and 100 mA per port.
This page synthesizes current distributor pricing, parametric drop-in alternatives, and practical design notes for the PIC16LC558-04I/P that supplement the manufacturer datasheet.
Drop-in alternatives for PIC16LC558-04I/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 PIC16LC558-04I/P (same form factor and footprint) — differing in Operating Temperature, Program Memory Size, Instruction Cycle Time, Package Type, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C558-04I/P
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.05 / Unit
View Datasheet →PIC16LC558-04/P
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.97 / Unit
View Datasheet →PIC16F627A-I/P
✅ Drop-In✓ In Stock
$1.72 / Unit
View Datasheet →PIC16LC558-04I/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (baseline, 14-bit instruction word) |
| Family | PIC16C5X baseline |
| Program Memory Size | 3.5 KB (2K x 14) OTP |
| RAM Size | 128 bytes |
| Maximum Clock Speed | 4 MHz |
| Instruction Cycle Time | 250 ns at 4 MHz |
| Supply Voltage (VDD) | 3 V to 6.25 V |
| I/O Pins | 13 |
| Number of I/O Ports | 2 (PORTA, PORTB) |
| Timers | 1 x 8-bit (TMR0 with prescaler) |
| Watchdog Timer | Yes (with on-chip RC oscillator) |
| Reset | Power-on Reset (POR) |
| Package Type | 18-pin PDIP (0.300 inch, 7.62 mm), through-hole |
| Operating Temperature | -40 °C to +85 °C (Industrial) |
| Mounting Type | Through-Hole |
PIC16LC558-04I/P Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O, PORTA bit 2 |
| Pin 2 | RA1 — Bidirectional I/O, PORTA bit 1 |
| Pin 3 | RA0 — Bidirectional I/O, PORTA bit 0 |
| Pin 4 | /MCLR — Master Clear (Reset), active-low input |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0 — Bidirectional I/O, PORTB bit 0 |
| Pin 7 | RB1 — Bidirectional I/O, PORTB bit 1 |
| Pin 8 | RB2 — Bidirectional I/O, PORTB bit 2 |
| Pin 9 | RB3 — Bidirectional I/O, PORTB bit 3 |
| Pin 10 | RB4 — Bidirectional I/O, PORTB bit 4 |
| Pin 11 | RB5 — Bidirectional I/O, PORTB bit 5 |
| Pin 12 | RB6 — Bidirectional I/O, PORTB bit 6 |
| Pin 13 | RB7 — Bidirectional I/O, PORTB bit 7 |
| Pin 14 | VDD — Positive supply voltage (3 V to 6.25 V) |
| Pin 15 | OSC2 — Oscillator output (crystal/RC) |
| Pin 16 | OSC1 — Oscillator input (crystal/RC) |
| Pin 17 | RA3 — Bidirectional I/O, PORTA bit 3 |
| Pin 18 | RA4 — Bidirectional I/O (open-drain), PORTA bit 4 |
Typical Applications
PIC16LC558-04I/P is suitable for 6 applications: Industrial Control Slave Modules, White Goods and Appliance UI Boards, Hobby Electronics and Education Kits, Sensor Front-End Signal Conditioning, Motor Control and Driver Slave Controllers, Remote Control Transmitter/Receiver Pairings.
Industrial Control Slave Modules
The PIC16LC558-04I/P fits industrial control slave modules that require deterministic 8-bit timing on legacy PLC backplanes. Its 4 MHz clock gives 1 µs instruction cycle granularity, adequate for sequencing solenoids, scanning opto-isolated inputs, and refreshing indicator LEDs at scan rates below 10 ms. The 13 I/O pins map cleanly to two 8-bit ports, simplifying PLC firmware that talks to upstream RS-485 masters. Compared with newer Cortex-M0 parts, the baseline PIC core consumes less current in sleep mode and survives -40 °C to +85 °C industrial ambient temperature without derating. The OTP memory is intentional: once production firmware is qualified, the MCU is locked and immune to field tampering. The 18-pin PDIP also suits retrofits where through-hole replacement is mandatory on existing field wiring.
Recommended
White Goods and Appliance UI Boards
In washing machines, dishwashers, and microwave ovens, the PIC16LC558-04I/P powers user-interface boards that drive seven-segment displays, scan keypads, and switch relays through triacs. Its 13 I/O pins handle a 4x4 keypad matrix plus 4-7 digit LED multiplexing without external logic. The 3 V to 6.25 V supply range matches raw rectified mains after buck regulation, eliminating the need for additional LDO stages. OTP memory keeps firmware cost below $0.30 BOM contribution at high volume, a key reason appliance OEMs continue to specify the PIC16C5X baseline family. The LC variant's low sleep current extends standby power budget to meet ENERGY STAR no-load requirements under 1 W. Industrial -40 to +85 °C operation covers garage and outdoor-appliance environments.
Recommended
Hobby Electronics and Education Kits
The PIC16LC558-04I/P remains popular in hobby and education platforms because the 18-pin PDIP is breadboard-friendly with 0.1 inch pin pitch. Students learn baseline RISC assembly with only 33 instructions, and the Harvard architecture (separate program/data buses) demonstrates concepts that scale up to modern ARM cores. The 4 MHz clock is comfortable for beginners learning timing loops without bus contention. OTP limitation is acceptable for kits since firmware is final once verified, and the $1.73-2.85 unit price (as of 2026-09-22) keeps student-project BOM affordable. The exposed through-hole pins also serve as convenient probe points for logic-analyzer labs. Microchip's MPLAB X IDE supports PIC16C5X assembly and C via the XC8 compiler, maintaining an active learning ecosystem.
Recommended
Sensor Front-End Signal Conditioning
The PIC16LC558-04I/P handles sensor front-end signal conditioning in simple thermostats, smoke detectors, and humidity monitors where its 4 MHz clock and 8-bit ALU compute moving averages and threshold comparisons without an ADC. The baseline PIC's bit-manipulation primitives make single-pin I/O control concise for resistive-sensor bridge excitation. The 3 V minimum supply suits 3.3 V regulated rails from a CR2032 or two AA cells. LC process variants draw under 5 µA in sleep mode, prolonging battery life in intermittently-sampled sensor nodes. OTP memory prevents accidental field reprogramming that could desensitize a safety-critical smoke alarm. Operating temperature -40 to +85 °C covers unheated attics and outdoor enclosures.
Recommended
Motor Control and Driver Slave Controllers
The PIC16LC558-04I/P acts as a slave controller next to a main DSP or MCU in stepper-motor and small-BLDC driver boards. It handles PWM generation via timer overflow tricks, direction sequencing, end-stop debouncing, and overcurrent fault shutdown. Its 4 MHz clock provides 1 µs resolution for step pulse timing on slow steppers up to 1000 pps. The 13 I/O pins map to step/dir/enable plus three limit switches and a fault output. Baseline PIC determinism - every instruction takes exactly one cycle - simplifies worst-case latency analysis for safety functions. Industrial temperature rating -40 to +85 °C covers motor housings. OTP memory locks calibrated motor parameters into production firmware. Low cost keeps slave-controller BOM contribution below $3 per axis.
Recommended
Remote Control Transmitter/Receiver Pairings
The PIC16LC558-04I/P implements low-cost RF/IR remote-control transmitters and receivers where 4 MHz is sufficient for Manchester-encoded bit streams at sub-1 kbps. The 13 I/O pins scan 4x4 keypads or 16-button matrices and drive a transmitter LED or 433 MHz SAW-based OOK modulator. Sleep current under 5 µA enables coin-cell operation for years. Industrial temperature rating covers outdoor garage-door and gate-controller environments. OTP memory locks pairing codes and rolling-key algorithms against cloning. 18-pin PDIP remains the dominant hobby and small-volume security hardware format. Compared with newer PIC16F enhanced baselines, the LC558 is preferred when re-programmability is undesirable (anti-tamper) and unit cost matters more than peripheral richness.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC558-04I/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C558-04I/P | PIC16LC558-04/P | PIC16LC558-04I/SO | PIC16C558-04I/SO | PIC16F627A-I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-PDIP (0.300 inch) | 18-PDIP (0.300 inch) - same | 18-PDIP (0.300 inch) - same | 18-SOIC (SMD, different footprint) | 18-SOIC (SMD, different footprint) | 18-PDIP (0.300 inch) - same |
| Program Memory | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 1.75 KB Flash |
| RAM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 224 bytes |
| Max Clock Speed | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz |
| I/O Pins | 13 | 13 | 13 | 13 | 13 | 16 |
| Operating Voltage | 3 V to 6.25 V | 3 V to 6.25 V | 3 V to 6.25 V | 3 V to 6.25 V | 3 V to 6.25 V | 2 V to 5.5 V |
| Operating Temperature | -40 °C to +85 °C (Industrial) | -40 °C to +85 °C (Industrial) | 0 °C to +70 °C (Commercial) | -40 °C to +85 °C (Industrial) | -40 °C to +85 °C (Industrial) | -40 °C to +85 °C (Industrial) |
| Memory Type | OTP | OTP | OTP | OTP | OTP | Flash (re-programmable) |
Key Differentiators
- Low-power CMOS LC process variant (vs PIC16C558-04I/P)
- Flash re-programmability for development (vs PIC16LC558-04I/P (OTP))
- Surface-mount option for compact designs (vs PIC16LC558-04I/P (PDIP))
Design Notes
The PIC16LC558-04I/P draws approximately 2 mA at 4 MHz and 5 V, dropping to under 5 µA in sleep mode (watchdog disabled). Place a 0.1 µF decoupling capacitor within 5 mm of the VDD pin (14) and a bulk 10 µF electrolytic on the supply rail. In noisy industrial environments add a ferrite bead on VDD to suppress conducted EMI from relays or motor drivers sharing the same 5 V rail. The LC process variant is preferred over the original PIC16C558 for battery-backed designs because quiescent current is roughly 30% lower.
For reliable oscillator operation on 18-pin PDIP, place the crystal or resonator within 10 mm of OSC1 (pin 16) and OSC2 (pin 15). Keep these traces short and guard them with a ground pour to minimize EMI coupling into adjacent signal traces. If using an external RC oscillator, place the resistor and capacitor close to OSC1 and bypass OSC2. The /MCLR pin (4) requires a 10 kΩ pull-up to VDD; some designs add a diode to VDD to protect against ESD-induced latch-up. Follow Microchip's 'Oscillator Layout Tips' application note for sensitive timing circuits.
Estimated: OTP memory on the PIC16LC558 can be programmed only once per cell - verify your firmware in a flash-equivalent (e.g., PIC16F627A-I/P) before committing to OTP production runs. Estimated: total sink/source current per pin is 25 mA and per port is 100 mA; exceeding this may damage the I/O driver. Do not leave unused I/O pins floating - configure them as outputs and tie to ground, or enable weak pull-ups if available. Do not apply voltage above 6.25 V on VDD or below -0.3 V on any pin including OSC inputs. Use /MCLR properly; floating /MCLR may cause intermittent resets in electrically noisy environments.
Compliance Information
Lifecycle status ACTIVE per distributor listings as of 2026-09-22. RoHS/REACH/lead-free status was not present in the Verified Web Data excerpt - confirm with Microchip product compliance documentation before EU shipments. Not AEC-Q100 qualified - this is an industrial-grade part, not automotive-grade.
