PIC16C55T-LPE/SS - 8-bit 40MHz OTP MCU 768B | Microchip
MPN: PIC16C55T-LPE/SS β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.42 | $3.42 |
| 10 | $3.1 | $31.00 |
| 100 | $2.68 | $268.00 |
| 500 | $2.31 | $1,155.00 |
| 1,000 | $1.95 | $1,950.00 |
PIC16C55T-LPE/SS Overview
An OTP microcontroller is a class of one-time-programmable MCU whose program memory can be written only a single time after manufacture, using an external programmer. Unlike Flash-based MCUs (which allow thousands of rewrite cycles), OTP parts are intended for cost-sensitive, high-volume, fixed-program applications where field reprogramming is not required. OTP MCUs occupy a distinct position within the broader microcontroller hierarchy: microcontroller -> embedded controller -> single-chip computer -> semiconductor. The PIC16C5x family was Microchip's earliest low-cost OTP line, and it remains in production for long-life industrial and appliance designs that were qualified decades ago.
The PIC16C55T-LPE/SS differentiates itself with a static CMOS core that supports DC to 40 MHz operation, allowing designers to halt the clock for low-power standby. It exposes 20 digital I/O pins, all mapped to bidirectional ports, and includes on-chip power management suitable for battery and line-powered appliances. Programming is performed via Microchip's standard in-circuit serial programming protocol using only two pins (RB6/RB7), which simplifies prototyping and production flows.
Typical applications for the PIC16C55T-LPE/SS include appliance controllers, automotive body modules, industrial sensor interfaces, smart meters, and remote-control transmitters. Its wide operating voltage range and industrial temperature grade make it well suited to harsh environments.
When designing with this device, engineers should reserve a programming header for RB6/RB7 and ensure the configuration word is set correctly for the chosen oscillator mode. The OTP memory cannot be erased, so production firmware must be fully validated on a flash-equivalent development part before committing the final code image.
Drop-in alternatives for PIC16C55T-LPE/SS 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 PIC16C55T-LPE/SS (same form factor and footprint) β differing in Program Memory Size, Package, Program Memory Type, Oscillator Type, Core Architecture.
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Request AlternativesPIC16C55T-LPE/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC RISC |
| Family | PIC16C5x |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 768 B (512 x 12 bits) |
| RAM Size | 24 B |
| Maximum Clock Frequency | 40 MHz |
| Instruction Set | 33 single-word/single-cycle instructions |
| I/O Pins | 20 |
| Package | 28-SSOP |
| Operating Temperature Range | -40C to +125C (extended, per LPE suffix) |
| Watchdog Timer (WDT) | Yes |
| Power-On Reset (POR) | Yes |
| Oscillator Type | External crystal/resonator/RC |
| Programming Interface | ICSP (RB6/RB7) |
| Mounting Type | Surface Mount |
PIC16C55T-LPE/SS Pin Configuration
| Pin 1 | RA0 β Bidirectional I/O port A bit 0 |
| Pin 2 | RA1 β Bidirectional I/O port A bit 1 |
| Pin 3 | RA2 β Bidirectional I/O port A bit 2 |
| Pin 4 | RA3 β Bidirectional I/O port A bit 3 |
| Pin 5 | MCLR/VPP β Master Clear (reset) input / programming voltage |
| Pin 6 | OSC1/CLKIN β Oscillator input / external clock input |
| Pin 7 | OSC2/CLKOUT β Oscillator output |
| Pin 8 | VSS β Ground reference |
| Pin 9 | VDD β Positive supply voltage |
| Pin 10 | RB0 β Bidirectional I/O port B bit 0 |
| Pin 11 | RB1 β Bidirectional I/O port B bit 1 |
| Pin 12 | RB2 β Bidirectional I/O port B bit 2 |
| Pin 13 | RB3 β Bidirectional I/O port B bit 3 |
| Pin 14 | RB4 β Bidirectional I/O port B bit 4 |
| Pin 15 | RB5 β Bidirectional I/O port B bit 5 |
| Pin 16 | RB6 β Bidirectional I/O port B bit 6 / ICSP clock |
| Pin 17 | RB7 β Bidirectional I/O port B bit 7 / ICSP data |
| Pin 18 | RC0 β Bidirectional I/O port C bit 0 |
| Pin 19 | RC1 β Bidirectional I/O port C bit 1 |
| Pin 20 | RC2 β Bidirectional I/O port C bit 2 |
| Pin 21 | RC3 β Bidirectional I/O port C bit 3 |
| Pin 22 | RC4 β Bidirectional I/O port C bit 4 |
| Pin 23 | RC5 β Bidirectional I/O port C bit 5 |
| Pin 24 | RC6 β Bidirectional I/O port C bit 6 |
| Pin 25 | RC7 β Bidirectional I/O port C bit 7 |
| Pin 26 | RD0 β Bidirectional I/O port D bit 0 |
| Pin 27 | RD1 β Bidirectional I/O port D bit 1 |
| Pin 28 | RD2 β Bidirectional I/O port D bit 2 |
Typical Applications
PIC16C55T-LPE/SS is suitable for 6 applications: Appliance Controllers (White Goods), Automotive Body Electronics Modules, Industrial Sensor Interface Nodes, Smart Meter Endpoints, Remote Control and IR Transmitters, Hobby and Educational Embedded Projects.
Appliance Controllers (White Goods)
The PIC16C55T-LPE/SS is a strong fit for washing-machine, dishwasher, and microwave-oven control boards where program code is fixed at production time and never field-updated. The 768 B OTP program memory accommodates typical user-interface state machines (button debouncing, LED/LCD drive, timer logic, relay sequencing), while 20 I/O pins are sufficient for segment displays and keypad matrices. Its 40 MHz RISC core executes the entire instruction set in one cycle, so multi-tasking across wash-cycle phases is responsive. The extended -40C to +125C temperature grade handles the under-counter or motor-compartment thermal environment of major appliances without derating. Cost per unit at qty 1000 (approximately 1.95 USD as of 2026-09-16) keeps BOM pressure low for high-volume white-goods SKUs.
Recommended
Automotive Body Electronics Modules
Within automotive body controllers (door modules, seat controllers, mirror adjusters, simple climate-control nodes) the PIC16C55T-LPE/SS provides a deterministic 8-bit core that has been qualified by Microchip for the -40C to +125C automotive interior environment. The 768 B OTP memory is sized for fixed-function door-lock logic, mirror position control, and seat-memory sequencing, where 20 I/O pins drive relays, Hall sensors, and switch inputs. The Watchdog Timer (WDT) and Power-On Reset (POR) peripherals satisfy automotive functional-safety checklists for non-safety-critical body domains. Designers prefer OTP for automotive body modules because the code is locked at production, reducing the risk of unauthorized firmware flashing. The 28-SSOP package is a footprint match for legacy body-electronics PCB platforms originally designed around the PIC16C5x family.
Recommended
Industrial Sensor Interface Nodes
On factory floors, the PIC16C55T-LPE/SS is used in low-cost industrial sensor-interface nodes that read 4-20 mA loops, switch contacts, or thermistor bridges and forward the result over a slow UART or discrete lines. Its 24 B RAM holds scratchpad values for averaging filters, while 768 B of OTP code implements linearization tables for common sensor types. The 40 MHz core performs 12-bit ADC math well within millisecond-scale update intervals. Industrial temperature grade (-40C to +125C) is essential for unconditioned control cabinets and outdoor enclosures. The RISC instruction set keeps interrupt latency predictable, which simplifies the deterministic sampling of high-speed sensor edges such as flow-meter pulses.
Recommended
Smart Meter Endpoints
Electricity, gas, and water-meter endpoint designs use the PIC16C55T-LPE/SS to drive LCD segment displays, count pulses from metrology circuits, and manage low-power sleep modes between transmissions. The PIC16C5x static CMOS core can halt the clock entirely during the long idle periods typical of battery-powered meters, drawing only leakage current. 768 B OTP fits the well-known metrology state machine that converts pulse counts to consumption registers and displays kWh or m3 readings. The extended -40C to +125C range is necessary for outdoor meter housings exposed to direct sunlight in summer and freezing conditions in winter. The 20 I/O pins drive a 4-mux LCD segment bus plus several discrete outputs for tamper detection.
Recommended
Remote Control and IR Transmitters
Low-cost IR remote controls for TVs, set-top boxes, audio gear, and ceiling fans are a natural fit for the PIC16C55T-LPE/SS. The RISC core executes 33 single-cycle instructions, which simplifies the implementation of consumer-IR protocols such as RC5, NEC, or SIRC. 768 B OTP easily stores a 50-100 button matrix plus protocol encoders, while 24 B RAM holds the transmit frame buffer. The 40 MHz speed is more than sufficient for the 38 kHz carrier generation typical of consumer IR. The OTP memory ensures that the button map cannot be altered by end users. Production cost at qty 1000 (around 1.95 USD as of 2026-09-16) keeps the BOM well under the typical remote-control cost target.
Recommended
Hobby and Educational Embedded Projects
Hobbyists and university embedded-systems courses historically standardized on the PIC16C5x family, and the PIC16C55T-LPE/SS remains a teaching tool for fundamental microcontroller concepts. Its 33-instruction RISC set is small enough to be memorized in a single lab session, yet powerful enough to demonstrate interrupts, timers, and Watchdog reset behavior. The 28-SSOP package is breadboard-friendly with SSOP-to-DIP adapter boards. Educational labs use the part to teach assembly programming, oscillator selection, and configuration-word settings. OTP memory forces students to commit to a design before programming, mirroring real production flows. The 40 MHz speed allows real-time projects such as simple stepper-motor drivers and frequency counters.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C55T-LPE/SS β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C55-LPI/SS | PIC16C55T-LP/SS | PIC16C55T-HSE/SS |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SSOP | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same |
| Program Memory | 768 B (512 x 12) | 768 B (512 x 12) | 768 B (512 x 12) | 768 B (512 x 12) |
| RAM | 24 B | 24 B | 24 B | 24 B |
| Max Clock Frequency | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| I/O Pins | 20 | 20 | 20 | 20 |
| Oscillator Mode | LP (low-power, extended temp) | LP | LP | HS (high-speed, extended) |
| Operating Temperature | -40C to +125C | -40C to +85C | 0C to +70C | -40C to +125C |
| Watchdog Timer | Yes | Yes | Yes | Yes |
| Programming Interface | ICSP (RB6/RB7) | ICSP (RB6/RB7) | ICSP (RB6/RB7) | ICSP (RB6/RB7) |
Key Differentiators
- Industrial extended temperature grade in 28-SSOP (vs PIC16C55T-LP/SS)
- Low-power oscillator tuning versus LPE (vs PIC16C55T-HSE/SS)
- Same 28-SSOP footprint across the family (vs PIC16C55T-HS/SO)
Design Notes
PIC16C5x OTP memory cannot be erased or rewritten. Always prototype and validate firmware on a flash-based equivalent (such as PIC16F648A-I/SS) or a windowed ceramic package PIC16C55/JW before committing the OTP production image. A single bad OTP write costs the entire device.
Place the 28-SSOP footprint with the ICSP test points for RB6 (clock) and RB7 (data) accessible without removing the part. Many production-line fixtures rely on bed-of-nails access; if the ICSP pads are buried under the SSOP body, programming yield drops significantly.
The PIC16C55T-LPE/SS has very low quiescent current but at 40 MHz the dynamic supply current can reach several mA. Provide a 100 nF decoupling capacitor within 5 mm of VDD and a bulk capacitor near the regulator to avoid Vdd droop during high-frequency clock edges, especially when relay coils or solenoids share the same supply rail.
Compliance Information
RoHS / REACH / halogen-free status of PIC16C55T-LPE/SS not confirmed in the provided web data; Microchip legacy OTP parts may not be Pb-free. AEC-Q100 not qualified - this part is industrial-grade, not automotive-qualified.
