PIC16LF18857-I/SO - 56KB Flash 32MHz 8-bit MCU | Microchip
MPN: PIC16LF18857-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.1 | $3.10 |
| 10 | $2.79 | $27.90 |
| 100 | $2.42 | $242.00 |
| 500 | $2.18 | $1,090.00 |
| 1,000 | $1.95 | $1,950.00 |
PIC16LF18857-I/SO Overview
What is a PIC16 8-bit microcontroller? A PIC16 is Microchip's mid-range 8-bit MCU architecture based on a 14-bit instruction set with a RISC-like Harvard core. PIC16 microcontrollers are used as the central controller in countless embedded products, from industrial sensors to consumer appliances. The XLP designation means this part supports sleep currents in the nanoamp range, deep-sleep retention, and active run currents below 100 uA/MHz, enabling years of battery life on coin-cell or lithium primary cells.
Key features include 256B of EEPROM data memory, 4KB of SRAM, up to 25 channels of 10-bit ADC2, 5-bit DAC, configurable logic cells (CLC), numerically controlled oscillator (NCO), complementary waveform generator (CWG), and zero-cross detect. The Peripheral Pin Select (PPS) allows nearly every digital peripheral to be remapped to a wide range of I/O pins, simplifying PCB routing. Hardware limit timers, windowed watchdog, and cyclic redundancy check (CRC/SCAN) provide functional-safety hooks for IEC 61508 SIL-2 capable designs.
The PIC16LF18857 uses a modified Harvard core with hardware multiplier and 49 instructions, including bit-oriented operations that map cleanly to C-compiled code. With 32MHz internal oscillator accuracy of +/- 1% over the industrial temperature range and 1.8V to 3.6V VDD operation, the device eliminates external crystals in most designs and integrates critical analog directly on-chip, reducing BOM cost.
Typical applications include battery-powered IoT sensor nodes, industrial process transmitters, low-power wireless Mote nodes, consumer white goods, HVAC controllers, medical handheld instruments, and automotive body electronics sub-modules. The 10-bit ADC2 with hardware averaging and oversampling makes it especially useful for bridge-sensor signal conditioning.
When designing with the PIC16LF18857-I/SO, reserve an RC network on MCLR for clean reset, decouple VDD with 100nF + 1uF ceramics, and consult MPLAB Code Configurator (MCC) plug-ins to generate peripheral initialization code. Programming is supported over ICSP using PICkit 4 or MPLAB Snap debuggers, and code may be developed in MPLAB X IDE with XC8 compiler.
Drop-in alternatives for PIC16LF18857-I/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 PIC16LF18857-I/SO (same form factor and footprint) — differing in ADC, Package, Core Architecture, Operating Temperature, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LF18855-I/SO
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View Datasheet →PIC16LF18856-I/SS
✅ Drop-In✓ In Stock
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View Datasheet →PIC16F18857-I/SO
✅ Drop-In✓ In Stock
$1.42 / Unit
View Datasheet →PIC16F18855-I/SO
✅ Drop-In✓ In Stock
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View Datasheet →PIC16LF18455-I/SO
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View Datasheet →PIC16LF18857-I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 8-bit RISC (14-bit instructions) |
| Family | XLP (eXtreme Low-Power) |
| Program Memory (Flash) | 56 KB |
| Data Memory (SRAM) | 4 KB |
| Data EEPROM | 256 B |
| CPU Speed | 32 MHz (max) |
| Operating Voltage (VDD) | 1.8 V to 3.6 V |
| Operating Temperature | -40C to +85C (Industrial) |
| ADC | 10-bit ADC2, up to 25 channels |
| DAC | 5-bit DAC |
| EUSART | 2 |
| SPI | 2 (shared with I2C) |
| I2C (MSSP) | 2 |
| Package | 28-pin SOIC (SO), 1.27mm pitch |
| Package Dimensions | 17.90 mm x 7.50 mm |
| Peripheral Pin Select (PPS) | Yes |
| Configurable Logic Cells (CLC) | Yes |
| Numerically Controlled Oscillator (NCO) | Yes |
| Complementary Waveform Generator (CWG) | Yes |
| Zero-Cross Detect | Yes |
| Windowed Watchdog Timer | Yes |
| CRC/SCAN | Yes |
| RoHS Status | Compliant |
| Mounting Type | Surface Mount |
PIC16LF18857-I/SO Pin Configuration
| Pin 1 | MCLR/VPP — Reset input / programming voltage |
| Pin 2 | RA0 — Port A bit 0 (PPS-capable) |
| Pin 3 | RA1 — Port A bit 1 (PPS-capable) |
| Pin 4 | RA2 — Port A bit 2 (PPS-capable, DAC output) |
| Pin 5 | RA3 — Port A bit 3 (PPS-capable) |
| Pin 6 | RA4 — Port A bit 4 / SOSC clock (shared) |
| Pin 7 | VSS — Ground reference |
| Pin 8 | RA5 — Port A bit 5 (PPS-capable) |
| Pin 9 | RA6 — Port A bit 6 (PPS-capable) |
| Pin 10 | RA7 — Port A bit 7 (PPS-capable, oscillator) |
| Pin 11 | VDD — Positive supply (1.8-3.6V) |
| Pin 12 | RB0 — Port B bit 0 (interrupt-on-change) |
| Pin 13 | RB1 — Port B bit 1 (interrupt-on-change) |
| Pin 14 | RB2 — Port B bit 2 (interrupt-on-change) |
| Pin 15 | RB3 — Port B bit 3 (interrupt-on-change) |
| Pin 16 | RB4 — Port B bit 4 (interrupt-on-change) |
| Pin 17 | RB5 — Port B bit 5 (interrupt-on-change) |
| Pin 18 | RB6 — Port B bit 6 (PPS-capable, ICSP clock) |
| Pin 19 | RB7 — Port B bit 7 (PPS-capable, ICSP data) |
| Pin 20 | RC0 — Port C bit 0 (PPS-capable) |
| Pin 21 | RC1 — Port C bit 1 (PPS-capable) |
| Pin 22 | RC2 — Port C bit 2 (PPS-capable) |
| Pin 23 | RC3 — Port C bit 3 (PPS-capable) |
| Pin 24 | RC4 — Port C bit 4 (PPS-capable) |
| Pin 25 | RC5 — Port C bit 5 (PPS-capable) |
| Pin 26 | RC6 — Port C bit 6 (PPS-capable) |
| Pin 27 | RC7 — Port C bit 7 (PPS-capable) |
| Pin 28 | VSS — Ground reference (alternate location) |
Typical Applications
PIC16LF18857-I/SO is suitable for 6 applications: Battery-Powered IoT Sensor Node, Industrial Process Transmitter, Consumer White Goods Control, Medical Handheld Instrument, HVAC Climate Controller, Automotive Body Electronics Sub-Module.
Battery-Powered IoT Sensor Node
The PIC16LF18857-I/SO is well matched to battery-powered IoT sensor nodes thanks to its XLP nanoamp sleep current and 32MHz/8MIPS CPU. With 56KB Flash for application + stack code and 4KB SRAM for buffers, the part can host a lightweight sensor-reading and radio-management routine that pairs with a Sub-GHz or BLE companion IC over one of the two EUSARTs. The 10-bit ADC2 with hardware oversampling can digitize thermistor, photo-diode, or bridge-sensor signals directly, while the CLC and NCO off-load simple signal conditioning from the CPU. Designers typically place the part next to a coin-cell holder and a 32.768 kHz watch crystal on SOSC for RTC tick.
Recommended
Industrial Process Transmitter
For 4-20 mA industrial transmitters, the PIC16LF18857-I/SO's 1.8-3.6V operation fits the loop-side electronics where a zener-regulated rail is standard. The 25-channel 10-bit ADC2 with computation can scan a strain-gauge bridge, RTD, or thermocouple pair with hardware oversampling for 14-bit effective resolution. PPS allows the SPI port to be remapped to clean PCB tracks, isolating the ADC inputs from the noisy digital section. The 256-byte EEPROM stores calibration coefficients, while the windowed WDT and CRC/SCAN support IEC 61508 SIL-2 functional-safety requirements typical of process instrumentation.
Recommended
Consumer White Goods Control
In washing machines, dishwashers, and induction cooktops, the PIC16LF18857-I/SO serves as the main user-interface and appliance controller. The 32MHz core drives the HMI, manages sensor inputs (water level, door switch, temperature NTC), and sequences the motor and heater. The Complementary Waveform Generator (CWG) can synthesize dead-band-corrected switching signals for the motor power stage, and the 5-bit DAC provides a programmable reference for op-amp based current sensing. With 56KB Flash the part absorbs feature-rich application code including inverter V/F control tables.
Recommended
Medical Handheld Instrument
For handheld medical devices like glucose meters, pulse oximeters, and spirometers, the PIC16LF18857-I/SO's low power profile enables weeks of operation on two AAA cells. The 10-bit ADC2 supports thermistor body-temperature sensing and the photo-detector front-end; PPS keeps analog and digital traces separate to preserve SNR. The 256B EEPROM can store patient calibration data, while the CLC implements custom pulse-detection logic that off-loads the CPU. Industrial-grade temperature range (-40C to +85C) supports sterilization environments.
Recommended
HVAC Climate Controller
In HVAC wall thermostats and zoning controllers, the PIC16LF18857-I/SO drives the LCD, reads NTC temperature sensors, manages the scheduler, and controls the contactor or TRIAC for the compressor. The CWG can synthesize zero-cross-switched TRIAC gate pulses for noiseless AC switching, while the NCO can drive a stepper motor for damper control. The two EUSARTs allow Modbus or BACnet communication over RS-485, and the 4KB SRAM is sufficient for schedule storage. PPS simplifies routing on the densely packed thermostat PCB.
Recommended
Automotive Body Electronics Sub-Module
Although the PIC16LF18857-I/SO is not AEC-Q100 qualified by default, it is widely used in non-safety automotive sub-modules such as interior LED drivers, seat-controller keypads, and ambient lighting nodes. The PPS, CLC, and NCO let engineers implement custom LIN-message handling, debounced switch scanning, and PWM color-mixing without glue logic. The PIC16LF18857-E/ML (extended temp) variant is preferred for under-dash deployments; for AEC-Q100 designs, PIC16F18857-I/SO is recommended for 5V rails while ensuring the rest of the BOM is automotive-grade.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LF18857-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LF18855-I/SO | PIC16LF18856-I/SS | PIC16F18857-I/SO | PIC16F18855-I/SO | PIC16LF18455-I/SO |
|---|---|---|---|---|---|---|
| Package | SOIC-28 (SO) | SOIC-28 (SO) - same | SSOP-28 (SS) - same 28-pin count | SOIC-28 (SO) - same | SOIC-28 (SO) - same | SOIC-28 (SO) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 56 KB | 28 KB | 32 KB | 56 KB | 28 KB | 14 KB |
| SRAM | 4 KB | 2 KB | 2 KB | 4 KB | 2 KB | 1 KB |
| EEPROM | 256 B | 256 B | 256 B | 256 B | 256 B | 256 B |
| CPU Speed | 32 MHz (8 MIPS) | 32 MHz (8 MIPS) | 32 MHz (8 MIPS) | 32 MHz (8 MIPS) | 32 MHz (8 MIPS) | 32 MHz (8 MIPS) |
| Operating Voltage | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 1.8 V to 3.6 V |
| ADC Channels | 25 channels 10-bit ADC2 | 24 channels 10-bit ADC2 | 24 channels 10-bit ADC2 | 25 channels 10-bit ADC2 | 24 channels 10-bit ADC2 | 17 channels 10-bit |
| EUSART / I2C / SPI | 2 / 2 / 2 | 2 / 2 / 2 | 2 / 2 / 2 | 2 / 2 / 2 | 2 / 2 / 2 | 2 / 2 / 2 |
| XLP Nanoamp Sleep | Yes | Yes | Yes | Yes (higher than LF) | Yes (higher than LF) | Yes |
Key Differentiators
- Highest Flash density in PIC16F1885x 28-SOIC family (vs PIC16LF18855-I/SO)
- Lower minimum operating voltage than F-version (vs PIC16F18857-I/SO)
- Most ADC channels in the 28-pin PIC16F1885x family (vs PIC16LF18455-I/SO)
Design Notes
Decouple VDD with a 100 nF ceramic capacitor placed within 5 mm of the VDD pin, plus a bulk 1 uF to 10 uF capacitor near the supply trace. The PIC16LF18857 XLP core has a wake-up time of ~1 ms from sleep; if your application cycles rapidly, use IDLE mode rather than full SLEEP. For battery designs on a CR2032 coin cell, the part can run for years at <1% duty cycle, but always include a Schottky diode reverse-protection block to prevent cell leakage during board assembly.
Estimated: route analog ADC inputs (RA0-RA5) with short traces and a guard ring tied to a quiet analog ground island, separated from the digital ground plane by a single bridge under the chip. Place the 32.768 kHz watch crystal as close as possible to RA4/RA5 (SOSC pins) with load capacitors grounded to the same quiet island. Avoid routing high-frequency signals across the analog traces; if PPS is used to remap, document the pin map in MPLAB MCC code for future reference.
Do not exceed the absolute maximum VDD of 4.0 V on the LF part; even brief transients above 3.6 V can corrupt the EEPROM and Flash endurance. The MCLR pin is rated for VDD + 0.3 V max in normal operation; for ICSP programming a VPP of ~8.5 V is applied but only via the Microchip debugger. Watch the I/O source current per pin (25 mA max) and total package dissipation (200 mA max) when driving LEDs - use a current-limit resistor and consider using the CLC + NCO for PWM-driven LED brightness to reduce CPU load.
Compliance Information
RoHS compliant per Microchip product page. -I suffix indicates industrial temperature range (-40C to +85C). Not AEC-Q100 qualified; for AEC-Q100 automotive use, choose PIC16F18857-E/ML (extended temp) or move to PIC18F-Q1 family.
