PIC16LC558-04/SO - 8-Bit 4MHz OTP MCU 3.5KB | Microchip
MPN: PIC16LC558-04/SO ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.59 | $5.59 |
| 10 | $5.03 | $50.30 |
| 100 | $4.47 | $447.00 |
| 500 | $3.65 | $1,825.00 |
| 1,000 | $2.85 | $2,850.00 |
PIC16LC558-04/SO Overview
An 8-bit microcontroller (MCU) is a single-chip processor that integrates a CPU, non-volatile program memory, working RAM, and peripheral I/O on one die. PIC16 microcontrollers are RISC-based Harvard-architecture devices: program memory and data memory use separate buses, and most instructions execute in one instruction cycle. The 16C sub-family specifically uses EPROM/OTP non-volatile memory rather than Flash, which historically made these parts cost-effective for low-volume or legacy products. Within the broader taxonomy, the PIC16LC558 sits under: PIC16 -> PIC16C sub-family -> PIC16LC5xx baseline series -> 8-bit microcontroller -> embedded MCU -> semiconductor IC.
Key features include 13 digital I/O, a Watchdog Timer with on-chip RC oscillator, Power-on Reset, Power-up Timer, and code protection. The architecture supports 33 single-word instructions with a 12-bit instruction word, a 14-bit wide program-memory bus, and interrupt handling for peripheral events. An 8-bit Timer/Counter0 with programmable prescaler is included.
Typical applications include consumer appliances, low-end remote controls, sensor interface modules, simple motor control, and replacement of discrete logic in legacy embedded designs. The 4 MHz ceiling suits bit-banged protocol and polling loops rather than high-throughput DSP.
Design tip: OTP memory cannot be re-programmed in-circuit; confirm firmware with a windowed or Flash equivalent (e.g., PIC16F or PIC16C558 JW) before committing to the OTP die. Also budget decoupling — a 0.1 µF cap close to VDD pin 14 and a bulk cap on VSS are mandatory.
This page synthesises distributor stock and pricing, drop-in alternatives in the same SOIC-18 footprint, and practical design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for PIC16LC558-04/SO — 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 PIC16LC558-04/SO (same form factor and footprint) — differing in Package, Program Memory Size, Watchdog Timer, Program Memory Type, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LC558-04I/SO
✅ Drop-In✓ In Stock
$1.1 / Unit
View Datasheet →PIC16LC558-04E/SO
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC16C558-04/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC554T-04I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.78 / Unit
View Datasheet →PIC16LC554T-04/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.85 / Unit
View Datasheet →PIC16LC558-04/SO Maximum Ratings & Electrical Characteristics
| Core | 8-bit PIC16 RISC (Harvard) |
| Instruction Set | 33 instructions, 14-bit wide |
| Program Memory | 3.5 KB (2K x 14) OTP EPROM |
| RAM | 128 x 8 bytes |
| EEPROM Data Memory | None (code-protection only) |
| I/O Pins | 13 general-purpose digital I/O |
| Maximum Clock Frequency | 4 MHz |
| Supply Voltage (VDD) | 2.5 V to 5.5 V |
| Operating Temperature | 0 °C to +70 °C (commercial) |
| Timers | 1 x 8-bit Timer/Counter0 with prescaler |
| Watchdog Timer | Yes, on-chip RC oscillator |
| Reset/Power Features | Power-on Reset, Power-up Timer, Oscillator Start-up Timer |
| Package | 18-pin SOIC (SO), 300 mil body |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited floor life) |
PIC16LC558-04/SO 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/T0CKI — I/O port A bit 4 / Timer0 clock input |
| Pin 4 | /MCLR — Master Clear reset input, active low |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — I/O port B bit 0 / external interrupt input |
| 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 2.5 V to 5.5 V |
| Pin 15 | OSC2/CLKOUT — Oscillator output / clock-out |
| Pin 16 | OSC1/CLKIN — Oscillator 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
PIC16LC558-04/SO is suitable for 6 applications: Consumer Appliance Control, Remote Control and IR Transmitter, Sensor Interface Module, Discrete Logic Replacement, Simple LED Lighting Controller, Automotive Cabin Accessory Module.
Consumer Appliance Control
The PIC16LC558-04/SO suits cost-sensitive consumer appliance control boards — washing-machine user interfaces, microwave keypads, and small kitchen-appliance motor drivers — where 13 GPIO are sufficient to scan a 4x4 matrix keypad plus drive a 7-segment or character LCD, and the 4 MHz CPU headroom runs polling loops comfortably without exceeding the 3.5 KB OTP program budget. The LC process variant minimises quiescent current drawn from the always-on +5 V rail when the appliance is in standby, helping meet IEC 62301 household-appliance standby-power limits. Its 18-SOIC footprint integrates cleanly onto single-sided FR-2 control boards used in mid-volume appliance production.
Recommended
Remote Control and IR Transmitter
For handheld remote controls, the PIC16LC558-04/SO provides 13 GPIO to drive a key matrix, an IR LED via Timer0 PWM, and indicator LEDs, while the LC low-power process keeps battery drain minimal between button presses. The 4 MHz clock easily bit-bangs consumer IR protocols (NEC, RC5, Sony SIRC) at 38 kHz carrier with 8-bit timer precision, and 128 bytes RAM is sufficient to buffer button debounce state plus protocol frame counters. OTP memory locks in the IR code table permanently so production units cannot be reprogrammed, which is often a deliberate anti-counterfeit requirement for TV/set-top accessories.
Recommended
Sensor Interface Module
The PIC16LC558-04/SO serves as a low-cost front-end in sensor-interface modules that aggregate digital inputs (e.g., reed switches, Hall-effect sensors, thermistor-bridge comparators) and forward status via GPIO to a higher-tier MCU or wired bus. Its 8-bit Timer0 with prescaler accurately timestamps events in 1 µs resolution at 4 MHz, and 128 bytes of RAM maintains a circular event buffer of ~64 events. The commercial 0 °C to +70 °C window suits indoor sensor hubs; industrial or outdoor modules should substitute the PIC16LC558-04I/SO or PIC16LC558-04E/SO to retain the same pinout over wider temperature swings.
Recommended
Discrete Logic Replacement
The PIC16LC558-04/SO is frequently used to consolidate 4 to 6 discrete TTL/CMOS logic packages — counters, multiplexers, shift registers, glue logic — into a single 18-SOIC part, reducing PCB area by 60 to 70 percent and BOM cost on legacy designs. With 13 GPIO and a 4 MHz instruction cycle of 1 µs, software state machines replace hardware glue while remaining easy to debug via standard PIC ICD in-circuit emulation on a JW (windowed) prototype. The OTP variant locks in proven state-machine code at production time and prevents field tampering with timing logic on industrial controllers.
Recommended
Simple LED Lighting Controller
In low-channel-count LED lighting controllers — under-cabinet strips, signage chasers, decorative lighting — the PIC16LC558-04/SO sequences 13 GPIO to drive MOSFETs or constant-current drivers with software-PWM dimming at 4 MHz. With 8-bit Timer0 prescaler set to 1:4, firmware can produce 8-bit PWM at roughly 1 kHz with 256 dimming steps per channel, sufficient for residential and decorative fixtures. The LC process keeps standby draw low in always-on fixtures, and the SOIC-18 footprint fits inside inline dimmer modules and junction-box mountings where board space is constrained.
Recommended
Automotive Cabin Accessory Module
Although commercial-grade, the PIC16LC558-04/SO finds use in non-critical automotive cabin accessories such as interior mood lighting drivers, vanity-mirror controllers and seat-position memory modules that operate within a closed thermal envelope. Designers replace it with the industrial-grade PIC16LC558-04I/SO for cabin reliability or migrate to AEC-Q100-qualified PIC16F88-I/SO when ISO 26262 functional-safety considerations enter the picture. The 18-pin SOIC footprint integrates onto small accessory PCAs, and 13 GPIO suffice for relay, switch-scan and indicator-LED multiplexing typical of these modules.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC558-04/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LC558-04I/SO | PIC16LC558-04E/SO | PIC16C558-04/SO | PIC16LC554T-04I/SO | PIC16LC554T-04/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-SOIC (300 mil) | 18-SOIC (300 mil) - same | 18-SOIC (300 mil) - same | 18-SOIC (300 mil) - same | 18-SOIC (300 mil) - same | 18-SOIC (300 mil) - same |
| Program Memory | 3.5 KB (2K x 14) OTP | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 1 KB OTP | 1 KB OTP |
| RAM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 80 bytes | 80 bytes |
| Max Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Operating Temperature | 0 C to +70 C (commercial) | -40 C to +85 C (industrial) | -40 C to +125 C (extended) | 0 C to +70 C (commercial) | -40 C to +85 C (industrial) | 0 C to +70 C (commercial) |
| Supply Voltage | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 3.0 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V |
| Process Variant | LC (low-power CMOS) | LC (low-power CMOS) | LC (low-power CMOS) | Standard CMOS (higher Iq) | LC (low-power CMOS) | LC (low-power CMOS) |
| I/O Pins | 13 | 13 | 13 | 13 | 13 | 13 |
Key Differentiators
- LC low-power CMOS process reduces quiescent current (vs PIC16C558-04/SO)
- Industrial temperature variant available in identical package (vs PIC16C558-04/SO)
- Larger program memory than PIC16LC554 family (vs PIC16LC554T-04I/SO)
Design Notes
Place a 0.1 µF ceramic decoupling capacitor within 5 mm of the VDD pin (pin 14) and a bulk capacitor (typically 4.7 to 10 µF tantalum or aluminium polymer) at the board entry point. The PIC16LC558-04/SO draws brief current spikes of 10 to 20 mA during internal EEPROM/OTP programming cycles and clock-edge transitions; inadequate decoupling will corrupt program memory or cause spurious resets via the brown-out detector. Estimated: at 4 MHz and 5 V VDD, core current draw is roughly 2 mA active plus 20 µA standby in LC process.
PIC16LC558 uses One-Time Programmable memory, so any bit-cell programmed in error cannot be erased. Always verify firmware on a JW (windowed) ceramic prototype or a Flash-equivalent (PIC16F88, PIC16F628A) before committing to the OTP plastic die for production. Also note that Microchip baseline PIC16C5xx instruction set differs from the mid-range PIC16F1xxx — the CLRF and BSF bit-set instructions behave subtly differently on port pins that are configured as inputs versus outputs, and failing to set the TRIS register leaves the pin in input mode.
The 18-SOIC (300 mil body) footprint needs 0.050 inch (1.27 mm) pin pitch with pad dimensions of approximately 0.060 x 0.090 inch. Route OSC1 (pin 16) and OSC2 (pin 15) traces short and surrounded by ground pour to minimise radiated EMI from the crystal oscillator. Keep /MCLR (pin 4) trace short and route a 10 kΩ pull-up to VDD plus a 100 nF cap to ground for clean reset behaviour. Estimated trace lengths: OSC traces < 10 mm, /MCLR < 15 mm.
The PIC16LC558-04/SO dissipates a maximum of approximately 200 mW in the 18-SOIC package under worst-case conditions. Thermal management is rarely critical at 4 MHz clock and 5 V VDD; the LC process keeps junction temperature rise modest. For enclosed industrial enclosures above 50 °C ambient, however, derate operating voltage to 5.0 V max and verify with a thermocouple on pin 14 (VDD) that junction temperature stays below 100 °C to maintain the OTP memory data-retention specification of > 40 years.
Compliance Information
RoHS and lead-free finish status not explicitly stated in verified web data — set to unknown pending datasheet document 40102E confirmation. Part is commercial temperature grade and is NOT AEC-Q100 qualified; choose PIC16LC558-04I/SO or PIC16LC558-04E/SO for industrial/extended-temp applications.
