PIC16LF873-04I/SO - 4MHz 8-bit PIC MCU, 7KB Flash | Microchip
MPN: PIC16LF873-04I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.5 | $8.50 |
| 10 | $7.65 | $76.50 |
| 100 | $6.8 | $680.00 |
| 500 | $6.1 | $3,050.00 |
| 1,000 | $5.45 | $5,450.00 |
PIC16LF873-04I/SO Overview
What is a PIC16 microcontroller? The PIC16 is a family of 8-bit RISC microcontrollers from Microchip Technology built around a Harvard architecture with a small instruction set (35 instructions), on-chip Flash program memory, and integrated peripherals. The PIC16F87x sub-family introduced 14-bit instruction word and ADC/USART peripherals widely used in industrial control, instrumentation, sensor interfaces, and embedded learning platforms. The PIC16LF87x 'LF' designation extends operating voltage down to 2.0V, making the family suitable for battery-powered and 3.3V-logic systems. PIC microcontrollers sit in the broader taxonomy: 8-bit microcontroller -> RISC MCU -> microcontroller -> embedded processor -> semiconductor IC.
Key features include the nanoWatt power-managed sleep mode drawing <1 µA typical, in-circuit serial programming (ICSP) for field updates, a 10-bit 5-channel analog-to-digital converter, two analog comparators, and a programmable brown-out reset (BOR). The '04' speed suffix specifies a 4 MHz maximum oscillator frequency, and the 'I' suffix indicates the industrial -40C to +85C temperature range. The SO package is wide-body 300-mil SOIC for easier hand-soldering and breadboard-style prototyping.
Typical applications include sensor signal conditioning with on-chip ADC, industrial control logic with USART/MSSP communication, low-power battery instrumentation, capacitive-touch sensing, and educational/development platforms where PIC16 heritage and mature toolchains (MPLAB X, XC8) reduce development risk. The LF variant's 2.0V minimum Vdd also enables direct coin-cell and 2xAA operation.
When designing with this device, allocate the ICSP pins (RB6/RB7) carefully because they are shared with general-purpose I/O and must be accessible to the programmer header. Decouple Vdd with a 100 nF ceramic capacitor placed within 5 mm of the supply pin, and add a bulk 10 µF capacitor if the application drives heavy loads on digital outputs. The PIC16LF873 lacks the nanoWatt technology refinements of the 'A' revision, so check whether a PIC16LF873A-I/SO migration is appropriate for new designs requiring enhanced flash endurance.
Drop-in alternatives for PIC16LF873-04I/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 PIC16LF873-04I/SO (same form factor and footprint) — differing in Core Architecture, Package, Timers, ADC, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LF873-04/SO
✅ Drop-In✓ In Stock
$3.4 / Unit
View Datasheet →PIC16LF873A-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF873-20I/SO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC16LF876A-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF873-04I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC16 RISC (Harvard) |
| Program Memory | 7 KB (4K x 14 words) Flash |
| RAM | 192 bytes |
| EEPROM | 128 bytes |
| Maximum CPU Clock | 4 MHz (external oscillator input) |
| Supply Voltage (Vdd) | 2.0 V to 5.5 V |
| Operating Temperature | -40C to +85C (industrial, 'I' suffix) |
| I/O Pins | 22 |
| ADC | 10-bit, up to 5 channels |
| Timers | 2 x 8-bit + 1 x 16-bit |
| Communication | USART + MSSP (I2C/SPI) |
| Comparators | 2 analog comparators |
| Package | 28-pin SOIC (wide-body, 7.50 mm, 'SO' / 300-mil) |
| Mounting Type | Surface Mount |
| ICSP | Yes (in-circuit serial programming) |
| Brown-Out Reset (BOR) | Programmable |
| Watchdog Timer | Yes |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC16LF873-04I/SO Pin Configuration
| Pin 1 | MCLR/Vpp — Master Clear (reset, active low) / Programming voltage input |
| Pin 2 | RA0/AN0 — Port A bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — Port A bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2/CVREF/VREF- — Port A bit 2 / Analog input 2 / Comparator Vref output / Vref- |
| Pin 5 | RA3/AN3/VREF+ — Port A bit 3 / Analog input 3 / Vref+ |
| Pin 6 | RA4/T0CKI/C1OUT — Port A bit 4 / Timer0 clock input / Comparator 1 output |
| Pin 7 | RA5/AN4/SS/C2OUT — Port A bit 5 / Analog input 4 / SPI slave select / Comparator 2 output |
| Pin 8 | Vss — Ground reference |
| Pin 9 | OSC1/CLKI — Oscillator crystal input / External clock input |
| Pin 10 | OSC2/CLKO — Oscillator crystal output / Clock output |
| Pin 11 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 12 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator input / CCP2 module |
| Pin 13 | RC2/CCP1 — Port C bit 2 / CCP1 module (PWM) |
| Pin 14 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 15 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 16 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 17 | RC6/TX/CK — Port C bit 6 / USART async transmit / USART sync clock |
| Pin 18 | RC7/RX/DT — Port C bit 7 / USART async receive / USART sync data |
| Pin 19 | Vss — Ground reference |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RB0/INT — Port B bit 0 / External interrupt |
| Pin 22 | RB1 — Port B bit 1 |
| Pin 23 | RB2 — Port B bit 2 |
| Pin 24 | RB3/PGM — Port B bit 3 / LVP programming entry |
| Pin 25 | RB4 — Port B bit 4 |
| Pin 26 | RB5/PGM — Port B bit 5 / Programming |
| Pin 27 | RB6/PGC — Port B bit 6 / ICSP clock |
| Pin 28 | RB7/PGD — Port B bit 7 / ICSP data |
Typical Applications
PIC16LF873-04I/SO is suitable for 7 applications: Industrial Sensor Interface with ADC, Low-Power Battery Instrumentation, USART/MSSP Communication Bridge, Educational Development Platforms, Home Appliance Control Board, Automotive Interior Body Electronics (non-safety), Hobbyist and Maker Project Hub.
Industrial Sensor Interface with ADC
The PIC16LF873-04I/SO is well-suited to industrial sensor signal-conditioning boards because its integrated 10-bit ADC with up to 5 analog channels handles multiple transducer inputs (thermistor bridges, photocurrents, 4-20 mA loops) without an external ADC. The 2.0-5.5V Vdd range accepts both 3.3V logic and 5V analog sensor rails, and the 22 digital I/O pins drive relay drivers and indicator LEDs directly. Programmable brown-out reset protects against brown-out conditions in long cable runs typical of factory floors. Engineers typically pair it with a 4-20 mA current loop transmitter such as XTR105 or a precision op-amp like MCP6002 for accurate signal acquisition across -40C to +85C.
Recommended
Low-Power Battery Instrumentation
The PIC16LF873-04I/SO's 'LF' designation enables direct operation from 2xAA cells (2.0-3.0V) or a single lithium coin cell with regulation, while the programmable brown-out reset protects data integrity as batteries discharge. The 4 MHz oscillator limit keeps active current draw low, and sleep mode with peripherals off reduces quiescent current to support multi-year battery life in remote sensor loggers. The 192-byte RAM suffices for averaging filters and basic state machines. For longer battery life consider migrating to PIC16LF873A-I/SO whose nanoWatt technology drops deep-sleep current below 1 nA typical. Suitable for wireless sensor nodes, data loggers, and remote monitoring tags.
Recommended
USART/MSSP Communication Bridge
The PIC16LF873-04I/SO integrates a hardware USART for RS-232/RS-485 links and an MSSP peripheral supporting both I2C and SPI master/slave operation, eliminating the need for a dedicated communication co-processor. This makes it ideal as a protocol-conversion bridge between legacy RS-485 sensor buses and I2C peripherals, or as a SPI master driving sensor arrays. The 28-pin SOIC footprint fits into compact interface modules and the industrial temperature range supports outdoor and factory-floor deployments. Common pairings include MAX485 for RS-485 transceivers and MCP2551 for CAN bus adaptation.
Recommended
Educational Development Platforms
The PIC16LF873-04I/SO has been a long-standing teaching platform in universities and embedded systems courses due to its simple 35-instruction RISC architecture, mature MPLAB X + XC8 toolchain (free download), and PICkit programmer compatibility. Students can program, debug, and observe GPIO toggling via ICSP on pins RB6/RB7 without removing the chip from the board. The wide-body SOIC package is friendly to breadboard adapters and hand-soldering training kits. Documentation, application notes (AN555, AN556), and code libraries are abundant, making it an excellent entry into microcontroller programming, interrupt handling, and peripheral configuration.
Recommended
Home Appliance Control Board
The PIC16LF873-04I/SO delivers the right balance of peripherals, I/O count, and cost for white-goods control boards such as washing machines, dishwashers, microwave ovens, and small HVAC controllers. The two analog comparators handle zero-crossing detection for triac-fired heater elements, the 22 I/O pins drive multiplexed 7-segment displays, keypad matrices, and relay outputs, and the USART links to inverter boards. The industrial -40C to +85C range covers appliance environments including under-cabinet and outdoor-rated units. Programmable BOR and watchdog timer provide the reliability margin required by safety-critical appliance standards (IEC 60335).
Recommended
Automotive Interior Body Electronics (non-safety)
While the PIC16LF873-04I/SO is not AEC-Q100 qualified, it is commonly deployed in cost-sensitive automotive interior modules (non-safety) such as ambient lighting controllers, seat position memories, and accessory timers where the -40C to +85C industrial temperature range suffices and warranty risk is contained. The 28-pin SOIC is solderable onto standard FR-4 PCBs with through-hole or surface-mount relays. For safety-critical applications (airbag, ABS, ECU) designers should select AEC-Q100 qualified alternatives such as PIC16F15323-I/SL or dsPIC33 families. The LF variant's 2.0V Vdd range also handles crank-down transient survival when paired with proper power conditioning.
Recommended
Hobbyist and Maker Project Hub
Maker and hobbyist communities favor the PIC16LF873-04I/SO because it combines an SOIC package (hand-solderable with a fine tip) with rich peripherals and an inexpensive PICkit programmer ecosystem. Projects include custom mechanical keyboards, addressable LED controllers, retro gaming consoles, and robotics motor controllers. The 22 I/O pins support multiple simultaneous peripherals - SPI display, I2C sensors, UART GPS, and PWM servo control - all from a single chip. Programming examples in C and assembly are widely published, and the open-source MPLAB X IDE runs on Windows, macOS, and Linux.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LF873-04I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LF873-04/SO | PIC16LF873A-I/SO | PIC16LF873-20I/SO | PIC16LF876A-I/SO |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC (wide-body, 7.50 mm) | 28-SOIC (wide-body, 7.50 mm) - same | 28-SOIC (wide-body, 7.50 mm) - same | 28-SOIC (wide-body, 7.50 mm) - same | 28-SOIC (wide-body, 7.50 mm) - same |
| Program Memory | 7 KB (4K x 14) Flash | 7 KB (4K x 14) Flash - same | 7 KB (4K x 14) Flash - same | 7 KB (4K x 14) Flash - same | 14 KB (8K x 14) Flash - superset (+100%) |
| Maximum CPU Frequency | 4 MHz | 4 MHz - same | 20 MHz (5x faster) | 20 MHz (5x faster) | 20 MHz (5x faster) |
| RAM | 192 bytes | 192 bytes - same | 192 bytes - same | 192 bytes - same | 368 bytes (+92%) |
| ADC Channels | 5 channels @ 10-bit | 5 channels @ 10-bit - same | 5 channels @ 10-bit - same | 5 channels @ 10-bit - same | 8 channels @ 10-bit (+60%) |
| Supply Voltage Range | 2.0 V to 5.5 V | 2.0 V to 5.5 V - same | 2.0 V to 5.5 V - same | 2.0 V to 5.5 V - same | 2.0 V to 5.5 V - same |
| Operating Temperature | -40C to +85C (industrial) | 0C to +70C (commercial) | -40C to +85C (industrial) | -40C to +85C (industrial) | -40C to +85C (industrial) |
| nanoWatt Power Management | No (basic sleep mode only) | No - same | Yes (deep sleep <1 nA typical) | No - same | Yes (deep sleep <1 nA typical) |
| 1pc Price (USD, as of 2026-09-25) | $8.50 | $8.20 (comparable) | $7.95 (similar) | $9.10 (comparable) | $9.40 (slightly higher) |
Key Differentiators
- Wide-body SOIC package simplifies prototyping and hand-soldering (vs PIC16LF873-04I/SP (PDIP-28))
- Industrial temperature range (-40C to +85C) versus commercial 0C to +70C variants (vs PIC16LF873-04/SO (commercial))
- Low-voltage (LF) silicon supports 2.0-5.5V operation versus standard F variant 4.0-5.5V (vs PIC16F873-04I/SO (no LF))
Design Notes
Place a 100 nF ceramic decoupling capacitor within 5 mm of the Vdd pin (pin 20) and route the ground return directly to the nearest Vss pin (pin 19) with a short, wide trace. Add a bulk 10 uF tantalum or ceramic capacitor on Vdd if any digital output drives currents above 20 mA aggregate. The 28-SOIC wide-body package has standard SOIC land patterns - no thermal pad to manage. Keep crystal traces short and symmetric; for 4 MHz operation the internal capacitance compensation handles standard AT-cut crystals without external loading caps. Place the ICSP header (RB6/RB7) on the board edge for programming access.
Do not confuse PIC16LF873-04I/SO (LF = 2.0-5.5V, this part) with PIC16F873-04I/SO (4.0-5.5V only). The two are pin-compatible but a 3.3V system will not boot on the F variant. The MCLR pin (pin 1) must be tied to Vdd through a 10 kohm resistor and a 100 nF cap to ground for proper reset; leaving MCLR floating causes intermittent failures. The 'I' suffix denotes industrial -40C to +85C; the non-I variant is commercial 0C to +70C. Verify your application operates only within the chosen temperature grade.
Route the ICSP signals RB6 (PGC) and RB7 (PGD) as a paired differential pair with ground on adjacent pins to minimize noise pickup during in-circuit programming. Keep analog input traces (RA0-RA5) away from digital switching signals (port C, oscillator pins) by at least 3x the trace-to-trace spacing to avoid ADC crosstalk. Place any external voltage reference for ADC Vref+ near pin 5 and decouple with 100 nF + 10 uF. Wide-body SOIC allows hand inspection of all pins but the wide pitch (1.27 mm) requires care when hand-soldering to avoid bridges.
For battery-powered designs, configure the PIC16LF873-04I/SO in sleep mode with peripherals disabled between measurement cycles. Estimated: at 4 MHz active current is approximately 1-2 mA typical at 3.3V; sleep current is approximately 1 uA typical with WDT disabled. For ultra-low-power applications requiring <1 uA deep sleep, migrate to PIC16LF873A-I/SO whose nanoWatt technology provides sub-1-nA typical deep-sleep current. Brown-out reset (BOR) should be enabled when operating from batteries to prevent code corruption during voltage droop.
Compliance Information
RoHS compliant per Microchip product page and DigiKey listing. Not AEC-Q100 qualified - select AEC-Q100 parts for automotive safety applications. Microchip received QS-9000 quality system certification in 1999.
