PIC16C71-04I/SO - 8-Bit 4MHz MCU with 4-Ch 8-bit ADC | Microchip
MPN: PIC16C71-04I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.1 | $4.10 |
| 10 | $3.62 | $36.20 |
| 100 | $3.05 | $305.00 |
| 500 | $2.65 | $1,325.00 |
| 1,000 | $2.32 | $2,320.00 |
PIC16C71-04I/SO Overview
An 8-bit PIC microcontroller is a RISC-based single-chip computer built on Harvard architecture with separate program and data buses, allowing instruction fetch and data access in a single cycle. Mid-range PIC16C devices sit between baseline PIC12/14 and enhanced PIC17/18 architectures, balancing code efficiency and I/O flexibility. OTP microcontrollers are programmed once and retain firmware for the lifetime of the part, making them well-suited for high-volume, cost-sensitive embedded products.
Key features of the PIC16C71-04I/SO include a 4-channel 8-bit ADC, 25 mA/25 mA high sink/source current on I/O pins, and a wide 2.0V to 6.0V operating voltage range. Low-power characteristics are 15 uA at 5V/4MHz and 1 uA standby at 3V/32kHz. The 4MHz rated frequency is suitable for control-loop and human-machine-interface tasks where computational throughput is moderate but deterministic timing matters.
Architecturally, the PIC16C71 uses a 14-bit instruction word and an 8-bit data path, with a hardware stack and interrupt controller supporting both internal and external sources. The integrated ADC eliminates the need for an external converter, reducing BOM cost and PCB area for sensor-interface designs.
Typical applications include entry-level A/D systems in automotive sensors, industrial controllers, appliance controls, and consumer electronics. Its combination of integrated ADC, OTP memory, and small SOIC footprint makes it a strong fit for high-volume embedded products. Consider verifying current lifecycle status before new designs, as the PIC16C71 family predates flash-based PIC16F successors such as the PIC16F716. According to the manufacturer datasheet, the PIC16C71X family shares pin and code compatibility across PIC16C710, PIC16C71, PIC16C711, and PIC16C715 variants. This page synthesizes distributor pricing, drop-in compatible alternatives, and practical design considerations for engineers evaluating legacy PIC designs.
Drop-in alternatives for PIC16C71-04I/SO — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C711-04I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C71-04I/SO Maximum Ratings & Electrical Characteristics
| Family | PIC16CXX mid-range |
| Core Architecture | 8-bit RISC, Harvard |
| Instruction Word | 14 bits |
| Program Memory Type | OTP (One-Time-Programmable) EPROM |
| Program Memory Size | 1.75 KB (1K x 14) |
| RAM | 36 bytes |
| Maximum Clock Frequency | 4 MHz |
| Operating Voltage Range | 2.0 V to 6.0 V |
| I/O Pins | 13 |
| ADC | 4 channels x 8-bit |
| I/O Sink/Source Current | 25 mA / 25 mA |
| Active Current (typ) | 15 uA at 5 V, 4 MHz |
| Standby Current (typ) | 1 uA at 3 V, 32 kHz |
| Temperature Range (I grade) | -40C to +85C (Industrial) |
| Package | 18-SOIC (SOIC-18) |
| Mounting Type | Surface Mount |
PIC16C71-04I/SO Pin Configuration
| Pin 1 | RA0/AN0 — Bidirectional I/O / analog input channel 0 |
| Pin 2 | RA1/AN1 — Bidirectional I/O / analog input channel 1 |
| Pin 3 | RA2/AN2 — Bidirectional I/O / analog input channel 2 |
| Pin 4 | RA3/AN3/Vref — Bidirectional I/O / analog input channel 3 / ADC voltage reference |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — Bidirectional I/O / external interrupt input |
| Pin 7 | RB1 — Bidirectional I/O |
| Pin 8 | RB2 — Bidirectional I/O |
| Pin 9 | RB3 — Bidirectional I/O |
| Pin 10 | RB4 — Bidirectional I/O |
| Pin 11 | RB5 — Bidirectional I/O |
| Pin 12 | RB6 — Bidirectional I/O |
| Pin 13 | RB7 — Bidirectional I/O |
| Pin 14 | VDD — Positive supply voltage (2.0V to 6.0V) |
| Pin 15 | OSC2/CLKOUT — Oscillator crystal output / clock output |
| Pin 16 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 17 | RA4/T0CKI — Bidirectional I/O / Timer0 clock input |
| Pin 18 | RA5/SS/AN4 — Bidirectional I/O / slave select / analog input channel 4 |
Typical Applications
PIC16C71-04I/SO is suitable for 6 applications: Industrial Sensor Interface, Appliance Control Board, Automotive Sensor Module (Entry-Level), Consumer Electronics Control, Battery-Powered Data Logger, HMI Keypad / Display Driver.
Industrial Sensor Interface
The PIC16C71-04I/SO integrates a 4-channel 8-bit ADC with 13 digital I/O lines in an 18-pin SOIC, making it a strong fit for industrial sensor-interface boards that need multiple analog inputs in a small footprint. Its 2.0V to 6.0V operating range and 4 MHz clock support control loops running at modest rates, while the wide industrial temperature grade (-40C to +85C) covers factory-floor enclosures. The 4 ADC channels are sufficient for sensor arrays like temperature, pressure, and flow transducers where 8-bit resolution is adequate. Typical implementation uses 1 ADC channel for the primary sensor, 1 for a redundant reference, and 2 for auxiliary monitoring, with the remaining I/O driving indicator LEDs and a serial link to a host controller. Compared with external ADC + MCU designs, the integrated converter reduces PCB real estate and BOM line items. Engineers should add external RC filtering on each ADC input to attenuate switching noise from nearby digital lines.
Recommended
Appliance Control Board
The PIC16C71-04I/SO suits white-goods and small-appliance control boards where a low-cost OTP MCU must drive relays, triac interfaces, and read sensors. Its 25 mA sink/source capability directly drives small relays or LED indicators without external transistors, while the 4 ADC channels handle temperature, water level, or humidity sensing. The 18-SOIC package is compatible with automated pick-and-place assembly, supporting high-volume appliance lines. Operating at 5V / 4 MHz, the device executes instructions at 1 MIPS, which is enough for proportional-control loops and human-machine-interface polling at 10-100 Hz. The OTP memory locks the firmware permanently, preventing field tampering with safety-relevant code in appliances like washing machines, dishwashers, and ovens. For designs that need field firmware updates, evaluate the PIC16F716-I/SO successor. Engineers should add TVS diodes on AC-coupled inputs and isolate mains-referenced signals from the MCU with optocouplers.
Recommended
Automotive Sensor Module (Entry-Level)
According to the Microchip product page, the PIC16C71 family is positioned for entry-level A/D applications in automotive, industrial, appliances, and consumer markets, and the PIC16C71-04I/SO with its integrated 4-channel 8-bit ADC fits automotive sensor modules that read a small number of analog signals at modest accuracy. Operating from a 5V vehicle rail with the wide 2.0V-6.0V input range, the MCU interfaces directly to resistive sensor bridges and thermistor networks. The industrial temperature grade covers under-dash and cabin-mounted modules. The 1.75 KB OTP memory stores calibration constants and simple control algorithms for non-safety-critical subsystems such as seat-position sensors, mirror-adjust feedback, or HVAC damper position sensing. Engineers should add reverse-battery protection and load-dump suppression on the supply rail, and verify automotive EMC conformance at the system level.
Recommended
Consumer Electronics Control
The PIC16C71-04I/SO suits consumer-product controllers that need an integrated ADC at the lowest possible unit cost. With 13 I/O pins, 4 ADC channels, and an 18-SOIC footprint, the device fits battery chargers, remote controls, toys, and small kitchen appliances where board space and BoM cost dominate. The OTP memory locks firmware permanently, protecting intellectual property in consumer products shipped by the millions. Active current of 15 uA at 5V/4MHz and standby current of 1 uA at 3V/32kHz allow battery-powered designs to extend operating life. The wide 2.0V-6.0V supply range accepts 3.3V or 5V rails directly. Engineers should add an external watchdog timer or use the PIC's internal WDT to recover from brown-out events in noisy consumer environments, and consider migrating to the PIC16F818/819 for designs that may need post-release firmware tweaks.
Recommended
Battery-Powered Data Logger
The PIC16C71-04I/SO with its 1 uA typical standby current at 3V/32kHz and integrated 4-channel 8-bit ADC is well suited to low-duty-cycle battery-powered data loggers that wake periodically, sample sensors, and return to standby. Operating from 2.0V-6.0V, the device runs directly from two alkaline cells or a single Li-ion cell with simple regulation. The 36 bytes of RAM limit per-sample buffering, but with 1.75 KB of program memory the firmware can implement compression, averaging, or store-and-forward logic. The OTP memory holds calibration coefficients across the battery's lifetime without EEPROM wear. Typical implementations wake every 1-10 seconds, sample 1-2 ADC channels, store results in a circular buffer, and transmit bursts over a UART or I2C link. Engineers should characterize total average current draw carefully and use the lowest practical clock frequency in standby to extend battery life.
Recommended
HMI Keypad / Display Driver
The PIC16C71-04I/SO with 13 I/O pins can scan a 3x4 or 4x4 matrix keypad (12-16 keys) while driving a small LED or character-LCD indicator, making it suitable as a dedicated human-machine-interface controller in larger systems. The 4 MHz clock delivers 1 MIPS of processing power, enough to debounce keys, decode multi-tap sequences, and update indicators at 50-100 Hz refresh. The integrated ADC channels are useful for backlight brightness control via a photodiode or potentiometer input. The OTP memory locks HMI behavior, preventing end-user modification of control sequences. The 18-SOIC package suits compact HMI boards mounted behind keypads or displays. Engineers should add ESD protection (TVS arrays) on keypad lines exposed to user contact, and use the internal pull-ups on PORTB to simplify keypad-scan firmware.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C71-04I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C711-04I/SO | PIC16C710-04/SS |
|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-SOIC | 18-SOIC - same footprint | SSOP-20 - different footprint |
| Core | 8-bit PIC mid-range | 8-bit PIC mid-range | 8-bit PIC mid-range |
| Max Clock Frequency | 4 MHz | 4 MHz | 4 MHz |
| Operating Voltage | 2.0 V to 6.0 V | 2.0 V to 6.0 V | 2.0 V to 6.0 V |
| Lifecycle / Type | Legacy OTP, active for existing designs | Legacy OTP, same family | Legacy OTP, same family |
Key Differentiators
- Pin- and code-compatible with PIC16C711 in same SOIC-18 footprint (vs PIC16C711-04I/SO)
- Larger program memory (1.75 KB) than PIC16C710 within same family (vs PIC16C710-04/SS)
- Integrated 4-channel 8-bit ADC eliminates external converter (vs PIC16C710-04/SS)
Design Notes
Estimated: At 5V VDD and 4 MHz clock, the PIC16C71-04I/SO draws approximately 15 uA active and 1 uA standby at 3V/32 kHz per the datasheet typical characteristics. For battery-powered designs, enable the SLEEP instruction and switch the oscillator to the internal low-frequency mode to extend battery endurance. Decouple VDD (pin 14) with a 100 nF ceramic capacitor placed within 5 mm of the supply pin, plus a bulk tantalum or aluminum cap of 1-10 uF at the board supply entry.
Do not confuse the OTP PIC16C71 with the flash-based PIC16F716/818/819. According to Microchip forum guidance, the F-series parts are pin-compatible but the peripheral register map differs in places, so firmware written for PIC16C71 will not run unmodified on PIC16F718 equivalents. Also note that the PIC16C71 lacks an internal oscillator on certain variants - verify the external crystal or RC network against the OSC1/OSC2 pin configuration in the datasheet.
Keep ADC analog traces (RA0-RA3, RA5) short and away from digital switching lines like RB outputs or oscillator traces. Use a ground plane to provide low-impedance return for the analog reference, and add a small capacitor (10-100 nF) at the Vref pin (RA3) if used as the ADC reference. Place the decoupling capacitor on VDD within one trace-width of the supply pin to minimize inductive ringing during transient current demands.
Compliance Information
Compliance status not explicitly stated in the verified web data. The PIC16C71 family is offered in commercial, industrial, and extended temperature grades per the manufacturer datasheet (DS30262A). For RoHS/REACH status, check the specific date code and the manufacturer declaration of conformity at order time.
