PIC16F18855T-I/SS - 8-bit XLP MCU, 14KB Flash, 28-SSOP | Microchip
MPN: PIC16F18855T-I/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.34 | $2.34 |
| 10 | $2.18 | $21.80 |
| 100 | $1.87 | $187.00 |
| 500 | $1.65 | $825.00 |
| 1,000 | $1.42 | $1,420.00 |
| 2,500 | $1.21 | $3,025.00 |
PIC16F18855T-I/SS Overview
An 8-bit microcontroller (MCU) is a self-contained compute subsystem built around a low-pin-count CPU core, on-chip non-volatile program memory, data SRAM, and a rich set of digital and analog peripherals. PIC microcontrollers from Microchip implement a RISC-based Harvard architecture with single-cycle instruction execution, making them deterministic and easy to use for real-time control. The PIC16F18855 belongs to the eXtreme Low-Power (XLP) family, which minimises active and sleep current to extend battery life in portable products.
Key features include 14KB self-programmable Flash (8K x 14 words), 1KB SRAM, 256 bytes EEPROM, 24 MHz internal HFINTOSC (selectable up to 32 MHz via 4x PLL), 10-bit ADC with Computation (ADC2), 5-/8-bit DAC, multiple comparators, 16-bit PWMs, configurable logic cells (CLC), zero-cross detect (ZCD), and a Hardware Limit Timer (HLT). CRC/SCAN and HLT peripherals support Functional Safety diagnostics commonly needed in IEC 60730-class designs.
Architecturally, the device pairs the enhanced mid-range PIC16 CPU with direct memory-mapped peripherals, allowing single-instruction access to most registers. eXtreme Low Power modes (sleep currents down to the nA range with peripheral wake) make the part suitable for energy-harvesting and always-on sensor nodes. The wide 2.3V–5.5V supply range simplifies interfacing to 3.3V and 5V analog front-ends.
Typical applications include industrial control panels, consumer appliances, low-power IoT sensor nodes, automotive body and comfort subsystems (with the VAO variant), battery-powered instrumentation, and Human-Machine Interface (HMI) drivers that need segmented LCD or PWM-controlled indicators.
When designing with this MCU, allocate the ICSP™/ICD pins (PGC/PGD) away from high-noise traces and provide a 100 nF decoupling capacitor adjacent to every VDD pin pair. The 28-SSOP footprint allows hand-soldering for prototypes while still supporting volume SMT assembly via the Tape-and-Reel format.
This page synthesizes distributor pricing, drop-in alternatives from the PIC16F18855 family, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC16F18855T-I/SS — 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 PIC16F18855T-I/SS (same form factor and footprint) — differing in Package, ADC, Core Independent Peripherals, Operating Temperature, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F18855-I/SSVAO
✅ Drop-In✓ In Stock
$2.08 / Unit
View Datasheet →PIC16F18855-I/SSVAO
✅ Drop-In✓ In Stock
$2.08 / Unit
View Datasheet →PIC16F18855-E/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F18855T-E/SSVAO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F18854-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F18855T-I/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 enhanced mid-range 8-bit RISC (Harvard) |
| Program Memory (Flash) | 14 KB (8K x 14 words) |
| Data SRAM | 1 KB |
| Data EEPROM | 256 bytes |
| Maximum CPU Frequency | 32 MHz (4x PLL from HFINTOSC) |
| Instruction Cycle Time | 125 ns @ 32 MHz |
| Operating Voltage (VDD) | 2.3 V to 5.5 V |
| I/O Pins | 25 (on 28-pin SSOP) |
| ADC | 10-bit ADC2 with Computation, up to [DATA_NEEDS 21 channels] |
| DAC | 5-bit and 8-bit DAC modules |
| Comparators | 2 rail-to-rail comparators |
| PWM Channels | 16-bit PWM with multiple outputs |
| Timers | Multiple 8/16-bit timers, HLT, SMT |
| Communication Peripherals | UART, SPI, I2C (MSSP), LIN-capable EUSART |
| Core Independent Peripherals | CLC, ZCD, NCO, CRC/SCAN, HLT |
| Functional Safety (FuSa) | Yes - IEC 60730 class-B support features |
| Low-Power Modes | XLP: nA sleep currents with RTCC |
| Operating Temperature | -40 C to +85 C (Industrial, "I") |
| Package | 28-pin SSOP (0.209" / 5.30 mm body width) |
| Mounting Type | Surface Mount (Tape & Reel, "T") |
| MSL Level | MSL1 (per JEDEC J-STD-020) |
| Lead-Free / RoHS | Yes - Compliant |
| Programming / Debug | ICSP (PGC/PGD), ICD |
PIC16F18855T-I/SS Pin Configuration
| Pin 1 | RA2/AN2 — Port A bit 2 / analog input 2 |
| Pin 2 | RA3/AN3 — Port A bit 3 / analog input 3 |
| Pin 3 | RA4/AN4 — Port A bit 4 / analog input 4 |
| Pin 4 | RA5/AN5 — Port A bit 5 / analog input 5 |
| Pin 5 | VDD — Positive supply (2.3V to 5.5V) |
| Pin 6 | VSS — Ground reference |
| Pin 7 | RA0/AN0 — Port A bit 0 / analog input 0 |
| Pin 8 | RA1/AN1 — Port A bit 1 / analog input 1 |
| Pin 9 | RB0/AN12 — Port B bit 0 / analog input 12 |
| Pin 10 | RB1/AN10 — Port B bit 1 / analog input 10 |
| Pin 11 | RB2/AN8 — Port B bit 2 / analog input 8 |
| Pin 12 | RB3/AN9 — Port B bit 3 / analog input 9 |
| Pin 13 | RB4 — Port B bit 4 |
| Pin 14 | RB5 — Port B bit 5 |
| Pin 15 | RB6/PGC — Port B bit 6 / ICSP clock (programming/debug) |
| Pin 16 | RB7/PGD — Port B bit 7 / ICSP data (programming/debug) |
| Pin 17 | RC0 — Port C bit 0 |
| Pin 18 | RC1 — Port C bit 1 |
| Pin 19 | RC2 — Port C bit 2 |
| Pin 20 | RC3 — Port C bit 3 |
| Pin 21 | RC4 — Port C bit 4 |
| Pin 22 | RC5 — Port C bit 5 |
| Pin 23 | RC6 — Port C bit 6 |
| Pin 24 | RC7 — Port C bit 7 |
| Pin 25 | RD0 — Port D bit 0 |
| Pin 26 | RD1 — Port D bit 1 |
| Pin 27 | RD2 — Port D bit 2 |
| Pin 28 | VSS — Ground reference (second VSS pin) |
Typical Applications
PIC16F18855T-I/SS is suitable for 6 applications: Low-Power IoT Sensor Nodes, Industrial Control Panels and HMI, Automotive Body and Comfort Electronics, Battery-Powered Instrumentation, Consumer Appliance Control Boards, Educational and Maker Development Boards.
Low-Power IoT Sensor Nodes
The PIC16F18855T-I/SS fits low-power IoT sensor nodes because its XLP architecture delivers nanoamp sleep currents while keeping the 8-bit PIC16 CPU instantly wakeable on peripheral events such as ADC threshold, ZCD or timer compare. With 14KB Flash it can run a Contiki-class or proprietary 6LoWPAN/BLE-frontend state machine plus UART/SPI/I2C drivers without external memory. The 25 I/O lines on 28-SSOP are sufficient to drive a sensor front-end plus a simple segmented-LCD or status LED. Industrial -40C to +85C rating allows outdoor or factory-floor deployment. Design tip: use Sleep mode with RTCC plus a single ADC2 channel to achieve multi-year battery life from a CR2032 cell.
Recommended
Industrial Control Panels and HMI
For industrial control panels the PIC16F18855T-I/SS provides 16-bit PWM, configurable logic cells (CLC), and 10-bit ADC2 with computation - ideal for driving indicator LEDs, opto-isolated inputs and rotary-encoder or matrix-keypad HMIs. The 32 MHz core delivers 8 MIPS, more than enough for protocol stacks and PID loops running concurrently. Functional Safety features (CRC/SCAN, HLT) help meet IEC 60730-class requirements for white goods and process-control equipment. The 28-SSOP footprint is easily hand-solderable for prototypes and reflow-solderable for production, simplifying NPI. Design tip: use the CLC to debounce quadrature encoder inputs in hardware, freeing CPU bandwidth for the application stack.
Recommended
Automotive Body and Comfort Electronics
The PIC16F18855T-I/SS is suitable for non-safety automotive body and comfort subsystems such as seat heaters, interior lighting, mirror control and HVAC actuators. The integrated EUSART with LIN auto-baud support enables LIN-slave node implementations for window lifters, mirror modules and door locks. For applications that require formal AEC-Q100 qualification, the SSVAO/VAO variant (PIC16F18855-I/SSVAO) drops into the same SSOP-28 footprint. The wide 2.3V-5.5V supply tolerates automotive load-dump transients with external TVS protection. Design tip: use ZCD plus a TRIAC driver stage for mains-dimmable AC lamp modules, and add the Hardware Limit Timer (HLT) to detect stuck keypad or relay faults.
Recommended
Battery-Powered Instrumentation
Battery-powered handheld instruments benefit from the PIC16F18855T-I/SS XLP architecture: deep sleep currents in the nanoamp range, fast wake from the RTCC or ADC2, and the 5-/8-bit DAC for sensor excitation or reference biasing. The 1KB SRAM and 14KB Flash comfortably support small data-logging stacks with SPI/I2C sensor front-ends. The industrial -40C to +85C rating covers cold-weather outdoor use. Design tip: enable the ADC2 hardware averaging and threshold-interrupt to keep the CPU asleep until a meaningful event is detected, dramatically reducing average current.
Recommended
Consumer Appliance Control Boards
White-goods and small appliance mainboards are well served by the PIC16F18855T-I/SS: 16-bit PWM drives brushed or BLDC small motors, the integrated comparators implement zero-cross dimmers, and the 10-bit ADC reads NTC temperature sensors for closed-loop heating control. Core Independent Peripherals (CLC, ZCD, NCO) handle timing-critical signal conditioning in hardware without CPU intervention. The 28-SSOP land pattern is well-supported by global EMS lines and minimises PCB area versus 40-pin devices. Design tip: leverage the Functional Safety (CRC/SCAN, HLT) blocks to meet IEC 60730 class-B without external watchdog parts.
Recommended
Educational and Maker Development Boards
The PIC16F18855T-I/SS is an excellent teaching MCU because it pairs the classic 8-bit PIC16 instruction set with modern CIPs and Functional Safety features, giving students exposure to both legacy and current embedded concepts. The 28-SSOP footprint works on standard breadboard-friendly adapter PCBs and the ICSP pins (PGC/PGD on RB6/RB7) integrate directly with the PICkit 4, MPLAB Snap and Curiosity development boards from Microchip. The free MPLAB X IDE, XC8 compiler and MCC configurator dramatically reduce the learning-curve. Design tip: use the CLC peripheral to teach hardware-state-machine concepts without writing interrupt code.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F18855T-I/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F18855-I/SS | PIC16F18855-I/SSVAO | PIC16F18855-E/SS | PIC16F18854-I/SS |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SSOP | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same |
| Flash Memory | 14 KB | 14 KB | 14 KB | 14 KB | 7 KB (-50%) |
| SRAM | 1 KB | 1 KB | 1 KB | 1 KB | 512 B (-50%) |
| EEPROM | 256 B | 256 B | 256 B | 256 B | 256 B |
| Max CPU Frequency | 32 MHz | 32 MHz | 32 MHz | 32 MHz | 32 MHz |
| Operating Voltage | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C | -40C to +125C (Auto) | -40C to +125C (Extended) | -40C to +85C |
| AEC-Q100 Qualified | No | No | Yes (VAO) | No | No |
| Reel / Tray Packing | Tape & Reel (T) | Tray (no T) | Tray | Tray | Tray |
Key Differentiators
- Tape-and-Reel ("T") packing format directly compatible with high-volume SMT lines (vs PIC16F18855-I/SS (tray packing))
- Core Independent Peripherals (CLC, ZCD, NCO, CRC/SCAN, HLT) on-chip (vs PIC16F18854-I/SS)
- Functional Safety (FuSa) IEC 60730-class B hardware features (vs PIC16F18855T-I/ML (QFN-28, same die))
Design Notes
Place a 100 nF X7R 0402/0603 ceramic decoupling capacitor within 3 mm of every VDD pin and a single 10 uF bulk capacitor near the IC. For battery-powered designs, leverage the PIC16F18855 XLP Sleep mode (nA-level current with RTCC active) and ADC2 threshold interrupts to keep the CPU asleep until a meaningful sensor event occurs. The wide 2.3V-5.5V range means a single 3.3V LDO is sufficient; do not add a 1.8V rail unless an external sensor requires it.
Route the ICSP lines PGC (RB6) and PGD (RB7) away from switching traces and PWM outputs. Keep PGC/PGD traces under 100 mm and provide a test-point or 100-mil header footprint for production-line programming. For SSOP-28, use a 0.65 mm pitch land pattern with solder-mask-defined (SMD) pads to reduce tombstoning during reflow. Avoid running long parallel traces under the IC to minimise coupling into the analog AVSS/AVDD pair.
Do not exceed 5.5V on any pin or VDD; the IC does not have 5V-tolerant I/O above the supply. When migrating from PIC16F18855T-I/SS to PIC16F18855-I/SSVAO for automotive qualification, the LATCH-UP and ESD characteristics change; verify IEC 61000-4-2 results on the final board. Also remember the "/SS" 28-SSOP variant and "/ML" 28-QFN variant share the pinout but require different PCB land patterns - mixing them produces assembly failures.
Although the 8-bit PIC16F18855T-I/SS rarely dissipates meaningful power (typically <100 mW at 32 MHz, 5V), verify SSOP-28 thermal resistance in thermally enclosed housings. Estimated: with theta_JA around 95 C/W on a 1-oz copper 4-layer JEDEC test board, full-load operation at 85 C ambient is fine. In an enclosed plastic appliance, derate ambient by 10-15 C to maintain margin and ensure the brown-out reset (BOR) is enabled to protect Flash during supply dips.
Compliance Information
Industrial -40C to +85C grade; AEC-Q100 only on VAO/SSVAO orderable parts. RoHS/REACH compliance stated by Microchip product page and distributor listings.
