PIC16C71-04/SO - 8-bit OTP MCU, 4MHz, 1.75KB, ADC | 18-SOIC
MPN: PIC16C71-04/SO β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.5 | $6.50 |
| 10 | $5.85 | $58.50 |
| 100 | $5.2 | $520.00 |
| 500 | $4.55 | $2,275.00 |
| 1,000 | $3.95 | $3,950.00 |
PIC16C71-04/SO Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, program memory, RAM, and peripherals. The PIC16C71 belongs to Microchip's mid-range 8-bit architecture, which uses a 14-bit instruction word with only 35 single-word instructions, making it easy to program in assembly while offering enough performance for embedded control. As an OTP-EPROM device, it is intended for low-to-medium volume production where flash reprogrammability is not required, typically industrial, appliance, automotive aftermarket, and consumer applications where cost dominates over in-field reprogrammability. PIC16C71 parts have been superseded in many designs by flash-based PIC16F equivalents.
The PIC16C71-04/SO delivers 200ns instruction execution at 4MHz clock input, true 8-bit arithmetic, hardware stack, watchdog timer, power-on reset, and the integrated 4-channel 8-bit ADC β a notable integration feature for a mid-1990s 8-bit MCU. Brown-out detection prevents code corruption at falling supply voltages, while the 13 I/O pins each carry individual TRIS direction control for mixed input/output bus designs. Device current is held below 2 mA typical at 5V/4MHz, and the part operates across the commercial 0C to +70C range (industrial -40C to +85C versions available separately).
Typical applications include entry-level A/D conversion in automotive sensors, industrial control panels, appliance user interfaces, and low-cost consumer electronics. The on-chip ADC eliminates an external converter and reduces BOM cost in measurement and monitoring designs. Designers should note that the PIC16C71-04 family has been surpassed by flash-based PIC16F devices; for new designs, the PIC16F818/819/716 are commonly cited pin-compatible flash replacements with backward-compatible ADC code paths.
Drop-in alternatives for PIC16C71-04/SO β 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 PIC16C71-04/SO (same form factor and footprint) β differing in Timers, Maximum Clock Frequency, Watchdog Timer, ADC, Core.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16C71T-04/SO
β Drop-Inβ In Stock
$1.79 / Unit
View Datasheet βPIC16C71-04S/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16F71-04/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16F818-04/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16C710-04/SO
β Drop-Inβ In Stock
$2.18 / Unit
View Datasheet βPIC16C711-04/SO
β Drop-Inβ In Stock
$3.32 / Unit
View Datasheet βPIC16C71-04/SO Maximum Ratings & Electrical Characteristics
| Family | PIC16CXX mid-range |
| Core | 8-bit PIC |
| Instruction Set Width | 14-bit |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 1.75 KB (1K x 14) |
| Data RAM | 36 bytes |
| Maximum Clock Frequency | 4 MHz |
| Instruction Execution Time | 200 ns |
| Number of I/O Pins | 13 |
| ADC Channels | 4 |
| ADC Resolution | 8-bit |
| Timers | 1 x 8-bit (Timer0 with 8-bit prescaler) |
| Brown-out Reset (BOR) | Yes |
| Watchdog Timer | Yes |
| Power-on Reset | Yes |
| Operating Supply Voltage | 5 V (4.5 V to 5.5 V) |
| Supply Current | < 2 mA typical at 5 V / 4 MHz |
| Operating Temperature Range | 0C to +70C (commercial) |
| Package | 18-SOIC (7.50 mm width, /SO suffix) |
| Mounting Type | Surface Mount |
| Pin Count | 18 |
| Instruction Count | 35 single-word instructions |
PIC16C71-04/SO Pin Configuration
| Pin 1 | RA2/AN2 β Bidirectional I/O / analog input channel 2 |
| Pin 2 | RA3/AN3 β Bidirectional I/O / analog input channel 3 |
| Pin 3 | RA4/T0CKI β Bidirectional I/O / Timer0 clock input |
| Pin 4 | /MCLR β Master clear (reset) input, active low |
| Pin 5 | GND β Ground reference |
| Pin 6 | RB0/INT β Bidirectional I/O / external interrupt input |
| Pin 7 | RB1 β Bidirectional I/O |
| Pin 8 | RB2 β Bidirectional I/O |
| Pin 9 | RB3 β Bidirectional I/O |
| Pin 10 | RB4 β Bidirectional I/O |
| Pin 11 | RB5 β Bidirectional I/O |
| Pin 12 | RB6 β Bidirectional I/O |
| Pin 13 | RB7 β Bidirectional I/O |
| Pin 14 | VDD β Positive supply (5 V) |
| Pin 15 | OSC2/CLKOUT β Oscillator output / clock output |
| Pin 16 | OSC1/CLKIN β Oscillator input / external clock input |
| Pin 17 | RA0/AN0 β Bidirectional I/O / analog input channel 0 |
| Pin 18 | RA1/AN1 β Bidirectional I/O / analog input channel 1 |
Typical Applications
PIC16C71-04/SO is suitable for 6 applications: Entry-Level Analog Sensor Reading, Industrial Control Panel MCU, Appliance User Interface Controller, Automotive Aftermarket Sensor Modules, Consumer Electronics Display Controllers, Battery-Powered Measurement Devices.
Entry-Level Analog Sensor Reading
The PIC16C71-04/SO integrates a 4-channel 8-bit ADC on-chip, eliminating an external converter and reducing BOM cost for sensor-reading designs in appliances, climate controls, and battery-powered monitors. Its 200ns instruction execution at 4MHz is adequate for polling sensors at sub-millisecond rates while the 36 bytes of RAM hold recent samples and state. The integrated ADC and Timer0 reduce PCB area and bill-of-materials cost.
Recommended
Industrial Control Panel MCU
At 5V operation with 4 MHz clock, 13 individually direction-controlled I/O, and Brown-out Reset, the PIC16C71-04/SO fits industrial control panels driving relays, keypads, and 7-segment displays. The 1.75 KB OTP program memory stores the main state machine and indicator logic, while the 8-bit Timer0 with 8-bit prescaler handles debouncing and watchdog timing. Housed in 18-SOIC, the chip reflows onto standard industrial PCBs.
Recommended
Appliance User Interface Controller
The PIC16C71-04/SO drives capacitive-touch-free user interfaces on washing machines, microwaves, and dishwashers, using the 4-channel 8-bit ADC to scan resistive touch panels and temperature sensors while the 13 I/O scan LED indicators and 7-segment displays. Its 5V supply and integrated ADC eliminate the need for external level shifters in 5V appliance electronics. Designers value its 35 single-word instructions for fast code development.
Recommended
Automotive Aftermarket Sensor Modules
Automotive aftermarket sensors (temperature, pressure, battery monitors) use the PIC16C71-04/SO's integrated 8-bit ADC to digitize analog sensor signals and its 5V-tolerant I/O to drive LIN/transceiver circuitry. The OTP-EPROM program memory prevents firmware reverse engineering, a security plus for aftermarket products. Borwn-out Reset ensures the MCU recovers cleanly from automotive supply transients.
Recommended
Consumer Electronics Display Controllers
Low-cost consumer electronics β kitchen timers, digital clocks, and simple toys β leverage the PIC16C71-04/SO's 13 I/O pins to drive multiplexed LED displays and read button matrices with minimal external logic. The 4 MHz clock supports 7-segment multiplexing refresh rates above 100 Hz, eliminating visible flicker. The OTP-EPROM and 18-SOIC package keep unit cost low for high-volume consumer SKUs.
Recommended
Battery-Powered Measurement Devices
The PIC16C71-04/SO operates from 5V with under 2 mA typical supply current at 4MHz, making it suitable for portable measurement devices like handheld thermometers and simple multimeter modules. Sleep/idle modes combined with the integrated Brown-out Reset allow long battery life and clean recovery from low-voltage events. The 4-channel ADC scans multiple sensors in handheld instruments.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C71-04/SO β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C71T-04/SO | PIC16C71-04S/SO | PIC16F71-04/SO | PIC16F818-04/SO | PIC16C710-04/SO | PIC16C711-04/SO |
|---|---|---|---|---|---|---|---|
| Package | 18-SOIC | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Type | OTP EPROM (1.75 KB) | OTP EPROM (1.75 KB) | OTP EPROM (1.75 KB) | Flash (1.75 KB) | Flash (1.75 KB) | OTP EPROM (0.5 KB) | OTP EPROM (1.75 KB) |
| Maximum Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz (20 MHz grade available) | 4 MHz grade (20 MHz grade available) | 4 MHz | 4 MHz |
| Instruction Execution Time | 200 ns | 200 ns | 200 ns | 200 ns | 200 ns | 200 ns | 200 ns |
| Data RAM | 36 bytes | 36 bytes | 36 bytes | 36 bytes | 128 bytes | 24 bytes (-33%) | 36 bytes |
| ADC Channels / Resolution | 4 x 8-bit | 4 x 8-bit | 4 x 8-bit | 4 x 8-bit | 5 x 10-bit (extra channel, higher resolution) | 4 x 8-bit | 4 x 8-bit |
| I/O Pins | 13 | 13 | 13 | 13 | 16 | 13 | 13 |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Active (recommended for new designs) | Active | Obsolete | Obsolete |
Key Differentiators
- Integrated 4-channel 8-bit ADC eliminated external converter (vs PIC16C710-04/SO)
- OTP security against firmware readback (vs PIC16F71-04/SO)
- Brown-out Reset included on-chip (vs External supervisory reset circuits on discrete-MCU designs)
Design Notes
Estimated: PIC16C71-04/SO is OTP-EPROM and cannot be reprogrammed. Do not use for development boards or any design where firmware revisions are expected β instead, prototype on a PIC16F71-04/SO (flash) and only commit to PIC16C71-04/SO for production runs where the firmware is final. OTP blank-windowed parts (PIC16C71-04/JW ceramic windowed package) are needed for PIC16C71 code iteration; the /SO is one-time only.
Estimated: At 5V and 4 MHz, the PIC16C71-04/SO draws under 2 mA typical active current. For battery-powered designs, exploit the SLEEP instruction (current drops to a few microamps) and use the Brown-out Reset to recover cleanly from low-voltage events. Add a 100 nF decoupling capacitor directly at VDD (pin 14) and a bulk capacitor at the board power entry for noise immunity.
Estimated: Place the 4 MHz crystal or resonator close to pins 15 (OSC2) and 16 (OSC1) with short symmetrical traces, and keep digital switching lines away from the RA0βRA3 analog inputs. The on-chip ADC performance degrades if analog traces run parallel to high-frequency digital traces; keep analog traces short and add a ground pour under the analog pins for ADC accuracy. /MCLR (pin 4) should be pulled up to VDD via 10 kΞ© and decoupled with a 100 nF capacitor for stable reset behavior.
Compliance Information
PIC16C71-04/SO is a legacy OTP-EPROM MCU from the mid-1990s that predates comprehensive RoHS/REACH declarations. RoHS and lead-free status not explicitly stated in the verified distributor listings β contact Microchip for the specific ordering codeβs lead-finish declaration. AEC-Q100 is not applicable for this commercial-temperature 8-bit MCU; an industrial-temperature variant exists separately.
