PIC16LF1939-I/P - 8-bit XLP MCU, 28KB Flash, 40-PDIP | Microchip
MPN: PIC16LF1939-I/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.9 | $3.90 |
| 10 | $3.51 | $35.10 |
| 100 | $3.12 | $312.00 |
| 500 | $2.81 | $1,405.00 |
| 1,000 | $2.5 | $2,500.00 |
PIC16LF1939-I/P Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, non-volatile program memory, volatile data memory, and peripheral interfaces on one die. The PIC16LF1939 sits inside the broader hierarchy: 8-bit MCU -> PIC16 family -> enhanced mid-range core -> eXtreme Low Power (XLP) sub-line -> flash-based microcontroller. The XLP designation indicates Microchip's low-power technology aimed at battery-powered and energy-harvesting applications where nanoWatt sleep currents and active-mode efficiency extend operating life. Understanding this hierarchy helps engineers map the device onto system-level power budgets and peripheral requirements.
Key features include 28KB self-programmable flash with 10,000 erase/write cycles, 256B of EEPROM with 1,000,000 erase/write cycles, an internal 16MHz oscillator, and a wide operating temperature range of -40C to +85C for the industrial-grade 'I' suffix. The device also offers a 10-bit ADC with up to 14 channels, multiple capture/compare/PWM modules, a master synchronous serial port (MSSP) for SPI/I2C, an enhanced USART, and nanoWatt XLP technology with multiple low-power sleep modes for battery applications. The 40-pin PDIP package is through-hole, easing breadboard and hand-soldering use in development and prototyping.
Technically, the PIC16LF1939 employs a Harvard architecture with separate program and data buses, a 14-bit instruction word, and a hardware stack. Its XLP technology provides sleep currents measured in nanoamperes with retention and wake-on-change, which is critical for remote sensor nodes and IoT endpoints that spend most of their life in sleep. The internal 16MHz oscillator eliminates one external component, and configurable oscillator modes (HF, XT, LF, RC, EC) let the developer trade frequency for current across the 32MHz maximum.
Typical applications include battery-powered sensor nodes, low-power IoT endpoints, industrial control panels, white goods and HVAC user interfaces, LED lighting controllers, and educational/development boards. The LF voltage range and XLP sleep currents make it a strong fit where energy budget is tight but 8-bit cost targets are mandatory. The 40-PDIP package also makes it ideal for hobbyists, training kits, and through-hole prototyping where surface-mount QFP variants are impractical.
When designing with the PIC16LF1939, note that the LF suffix limits VDD to 3.6V maximum. If your application runs from a 5V rail, use the PIC16F1939 (F variant, 1.8V-5.5V) instead - it is pin-to-pin compatible within the same package family. Decoupling VDD/VSS with at least one 100nF ceramic per supply pin placed within 5 mm of the package is mandatory to keep the ADC accurate and to suppress switching noise.
This page synthesizes distributor pricing as of 2026-09-25, drop-in PDIP-40 alternatives, and practical design notes not found in the manufacturer datasheet - giving engineers a single consolidated reference for sourcing, replacement, and design-in decisions.
Drop-in alternatives for PIC16LF1939-I/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 PIC16LF1939-I/P (same form factor and footprint) — differing in Timers, ADC, Operating Temperature, Package, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F1939-I/PT
✅ Drop-In✓ In Stock
$3.42 / Unit
View Datasheet →PIC16LF1938-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF1937-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF1936-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F1939-E/P
✅ Drop-In✓ In Stock
$2.65 / Unit
View Datasheet →PIC16LF1939-I/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 enhanced mid-range 8-bit |
| Program Memory (Flash) | 28KB (16K x 14 words) |
| Data SRAM | 1KB |
| Data EEPROM | 256B |
| Maximum CPU Clock | 32 MHz |
| Instruction Cycle | 200 ns at 20 MHz / 125 ns at 32 MHz |
| Operating Voltage (VDD) | 1.8 V to 3.6 V (LF variant) |
| I/O Pins | 36 |
| ADC | 10-bit, multi-channel |
| Timers | Multiple 8/16-bit timers with CCP/PWM |
| Communication | 1x MSSP (SPI/I2C), 1x Enhanced USART |
| Package / Case | 40-pin PDIP (DIP-40) |
| Mounting Type | Through Hole |
| Operating Temperature | -40 C to +85 C (industrial 'I') |
| XLP Technology | Yes - nanoWatt eXtreme Low Power |
| RoHS Status | Compliant |
| MSL Level | 1 (unlimited floor life) |
PIC16LF1939-I/P Pin Configuration
| Pin 1 | RA0/AN0/ULPWU — PORTA bit 0 / analog input / ultra-low-power wake-up |
| Pin 2 | RA1/AN1 — PORTA bit 1 / analog input |
| Pin 3 | RA2/AN2 — PORTA bit 2 / analog input |
| Pin 4 | RA3/AN3/VREF+ — PORTA bit 3 / analog input / VREF+ |
| Pin 5 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 6 | RA5/AN4/SS — PORTA bit 5 / analog input / SPI slave select |
| Pin 7 | RA6/OSC2/CLKO — PORTA bit 6 / oscillator output / clock output |
| Pin 8 | RA7/OSC1/CLKI — PORTA bit 7 / oscillator input / clock input |
| Pin 9 | RE3/MCLR/VPP — PORTE bit 3 / master clear / programming voltage |
| Pin 10 | VDD — Positive supply voltage |
| Pin 11 | VSS — Ground reference |
| Pin 12 | RB0/INT/AN12 — PORTB bit 0 / external interrupt / analog input |
| Pin 13 | RB1/AN10 — PORTB bit 1 / analog input |
| Pin 14 | RB2/AN8 — PORTB bit 2 / analog input |
| Pin 15 | RB3/AN9/CCP2 — PORTB bit 3 / analog input / CCP2 |
| Pin 16 | RB4/AN11 — PORTB bit 4 / analog input |
| Pin 17 | RB5/AN13 — PORTB bit 5 / analog input |
| Pin 18 | RB6/ICSPCLK — PORTB bit 6 / ICSP clock |
| Pin 19 | RB7/ICSPDAT — PORTB bit 7 / ICSP data |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | VSS — Ground reference |
| Pin 22 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator / clock input |
| Pin 23 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator / CCP2 |
| Pin 24 | RC2/CCP1 — PORTC bit 2 / CCP1 |
| Pin 25 | RC3/SCL/SCK — PORTC bit 3 / I2C SCL / SPI SCK |
| Pin 26 | RC4/SDA/SDI — PORTC bit 4 / I2C SDA / SPI SDI |
| Pin 27 | RC5/SDO — PORTC bit 5 / SPI SDO |
| Pin 28 | RC6/TX/CK — PORTC bit 6 / USART TX / clock |
| Pin 29 | RC7/RX/DT — PORTC bit 7 / USART RX / data |
| Pin 30 | RD0 — PORTD bit 0 |
| Pin 31 | RD1 — PORTD bit 1 |
| Pin 32 | RD2 — PORTD bit 2 |
| Pin 33 | RD3 — PORTD bit 3 |
| Pin 34 | RD4 — PORTD bit 4 |
| Pin 35 | RD5 — PORTD bit 5 |
| Pin 36 | RD6 — PORTD bit 6 |
| Pin 37 | RD7 — PORTD bit 7 |
| Pin 38 | RE0 — PORTE bit 0 |
| Pin 39 | RE1 — PORTE bit 1 |
| Pin 40 | RE2 — PORTE bit 2 |
Typical Applications
PIC16LF1939-I/P is suitable for 6 applications: Battery-Powered Sensor Nodes, Low-Power IoT Endpoints, Industrial Control Panels, LED Lighting Controllers, Educational / Development Boards, White Goods & HVAC User Interfaces.
Battery-Powered Sensor Nodes
The PIC16LF1939-I/P fits battery-powered wireless sensor nodes because its nanoWatt XLP sleep current extends coin-cell life into the multi-year range. With 28KB flash and 1KB RAM, it can run a small RF protocol stack, sensor sampling, and MAC-layer scheduling. The 1.8V-3.6V VDD range aligns directly with single- or dual-AA battery chemistries without an extra regulator, and the 10-bit ADC handles most analog sensor front-ends at 3.3V. Compared with running from a switching regulator, the LF device's low quiescent draw keeps the node's idle energy budget below 1 uA.
Recommended
Low-Power IoT Endpoints
For IoT endpoints reporting periodically over SPI/UART radios, the PIC16LF1939-I/P delivers enough code space (28KB flash) for command interpreters, sensor drivers, and security stacks while remaining inside a tight sleep-mode energy budget. Its MSSP peripheral supports SPI/I2C sensors and the USART drives radios transparently. The 36 I/O pins allow multiple sensors, indicator LEDs, and a user button on one chip. At 32MHz the device can execute complex protocol payloads in milliseconds, leaving the rest of the duty cycle in deep sleep.
Recommended
Industrial Control Panels
Industrial control panels benefit from the PIC16LF1939-I/P's 36 I/O for keypad scan, multiple LED/PWM indicators, and relay or triac drivers. The MSSP/I2C bus can interface with EEPROM, RTC, and IO expanders, while the USART handles RS-232/RS-485 comms. The LF voltage range allows 3.3V-only subsystems but, with the F-variant drop-in, the same PCB can run from 24V->5V rails. Enhanced CCP/PWM modules drive proportional valves, dimmers, and motor speed references. The 40-pin PDIP simplifies rework and field replacement.
Recommended
LED Lighting Controllers
The PIC16LF1939-I/P is well suited to architectural and accent LED controllers because its 10-bit ADC reads ambient light sensors and potentiometer dimmers, while multiple CCP/PWM channels drive MOSFET gates for smooth color mixing or dimming curves. The XLP sleep current is small enough for a battery-backed or capacitor-stored emergency LED. The 1.8V-3.6V range pairs with constant-current LED drivers that already run on 3.3V. Combined with internal 16MHz oscillator and 32MHz max, animations and fades stay smooth even with 4-channel RGBW output.
Recommended
Educational / Development Boards
Universities and training courses prize the 40-pin PDIP through-hole package because it accepts solderless breadboards and discrete-hook wiring without special tools. The PIC16LF1939-I/P's 32MHz core, 28KB flash, and full peripheral set (ADC, MSSP, USART, CCP/PWM) make it a capable target for teaching C, assembly, and embedded peripherals in one device. MPLAB X IDE and XC8 compiler are free, and the PICkit programmer targets the package directly. Compared with surface-mount QFP variants, the PDIP cuts student setup time to seconds.
Recommended
White Goods & HVAC User Interfaces
White-goods user interfaces (washing-machine, dishwasher, oven front panels) and HVAC thermostats use the PIC16LF1939-I/P for keypad scan, seven-segment or LCD segment display multiplexing, and triac/relay control. The 36 I/O allow matrix keypads plus multiple LEDs without external expanders, and the ADC reads NTC temperature sensors for HVAC. The -40C to +85C industrial temperature rating covers unheated appliance interiors. The 28KB flash easily fits UI state machines, fault logging, and basic energy-meter code on a single chip.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LF1939-I/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F1939-I/P | PIC16LF1938-I/P | PIC16LF1937-I/P | PIC16LF1936-I/P | PIC16F1939-E/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 40-pin PDIP | 40-pin PDIP - same | 40-pin PDIP - same | 40-pin PDIP - same | 40-pin PDIP - same | 40-pin PDIP - same |
| Operating Voltage (VDD) | 1.8V to 3.6V | 1.8V to 5.5V | 1.8V to 3.6V | 1.8V to 3.6V | 1.8V to 3.6V | 1.8V to 5.5V |
| Program Flash | 28KB (16K x 14) | 28KB (16K x 14) | 16KB | 8KB | 16KB | 28KB (16K x 14) |
| Data RAM | 1KB | 1KB | 1KB | 1KB | 1KB | 1KB |
| Data EEPROM | 256B | 256B | 256B | 256B | 256B | 256B |
| Maximum Clock | 32 MHz | 32 MHz | 32 MHz | 32 MHz | 32 MHz | 32 MHz |
| Operating Temperature | -40C to +85C (industrial) | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +125C (extended) |
Key Differentiators
- Higher flash density in the same 40-pin PDIP (vs PIC16LF1938-I/P)
- Lower-voltage low-power variant with XLP technology (vs PIC16F1939-I/P)
- Industrial temperature grade for harsh environments (vs PIC16F1939-E/P)
Design Notes
Place a 100nF ceramic decoupling capacitor within 5 mm of each VDD/VSS pair (the 40-pin PDIP has two pairs at pins 10/11 and 20/21). Add a bulk 10uF tantalum or ceramic near the supply entry point to suppress transient load when the ADC, MSSP, or PWM modules switch. For battery applications, route AVdd and AVss separately and drive AVdd from a low-noise LDO (not a switching regulator) to keep ADC accuracy within 1 LSB at 10-bit resolution.
Keep the ICSP clock (RB6/ICSPCLK) and ICSP data (RB7/ICSPDAT) lines short and isolated from analog signals. The MCLR pin (RE3, pin 9) requires a 10k pull-up to VDD and a 100nF to ground for stable reset; some programmers add a diode for high-voltage VPP injection. Avoid routing the 32MHz oscillator traces near high-current switching nodes; use a ground guard ring around the crystal and keep traces symmetric and short.
Do not confuse the LF voltage suffix with the F voltage suffix: PIC16LF1939-I/P tops out at 3.6V, but PIC16F1939-I/P goes to 5.5V. If you replace one with the other on a 5V rail without checking, the LF variant will latch up and fail. Also confirm CONFIG register settings for the oscillator and WDT before deployment - a default WDT can reset the device during long blocking delays. Estimated: LF sleep current is in the nA range at room temperature per the PIC16F/LF193x family datasheet - actual current depends on WDT, BOR, and peripherals enabled.
Compliance Information
RoHS compliant per Microchip product page. Lead-free matte-tin finish. AEC-Q100 is not applicable for this industrial-grade MCU; for automotive-grade equivalents look at the PIC16F1939-E/P (extended temperature).
