PIC16F631-E/P - 8-Bit 20MHz 1.75KB Flash MCU | Microchip | DIP-20
MPN: PIC16F631-E/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.05 | $2.05 |
| 10 | $1.84 | $18.40 |
| 100 | $1.62 | $162.00 |
| 500 | $1.45 | $725.00 |
| 1,000 | $1.29 | $1,290.00 |
PIC16F631-E/P Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, volatile and non-volatile memory, and programmable I/O peripherals. The PIC16F631 belongs to the mid-range PIC16 architecture, sitting hierarchically as: microcontroller -> embedded controller -> CMOS microcontroller -> 8-bit MCU -> PIC16 family -> mid-range x14 core. Its 14-bit instruction word delivers 200ns instruction execution at 20MHz, with only 35 single-word instructions, which makes the part accessible for both new designers and seasoned embedded engineers.
Key features of the PIC16F631 include nanoWatt Technology for low-power operation, integrated EEPROM data memory, a wide 2.0V to 5.5V operating voltage range, 12 I/O pins with selectable weak pull-ups, an enhanced 8-bit timer/counter (Timer1) with its own oscillator, an analog comparator module, and a 10-bit ADC. The nanoWatt sleep modes and dynamic switching of oscillator sources allow the device to draw microamp-level currents in standby - useful for battery-powered designs.
Architecturally, the PIC16F631 uses a Harvard RISC core with separate program and data buses, two 8-bit file-select registers (FSR) for indirect addressing, a hardware interrupt controller, and an in-circuit serial programming (ICSP) interface for field updates. The 10-bit A/D converter is shared with digital I/O on PORTA, while PORTC carries general-purpose I/O and the analog comparator outputs. Internal oscillator options (8MHz LF-INTOSC and 31kHz LF-INTOSC) reduce external component count.
Typical applications include consumer appliance control, sensor signal conditioning, low-end motor control loops, LED lighting controllers, and battery-powered remote controls. Its small footprint and extended temperature range also suit industrial sensor nodes and automotive body controllers. According to Microchip datasheet 40001262F, the device supports 100,000 erase/write cycles on Flash and 1,000,000 erase/write cycles on EEPROM, ensuring long field life.
When designing with the PIC16F631, consider that the E-suffix part is qualified for -40°C to +125°C operation, while the I-suffix is only -40°C to +85°C. Decoupling capacitors (100nF ceramic + 10uF bulk) should be placed within 5mm of VDD, and the MCLR pin must have a pull-up and decoupling for reliable reset. Unused I/O should be configured as outputs and tied low to minimize power consumption.
This page synthesizes distributor pricing, drop-in PIC16F630 alternatives, and practical design notes that go beyond the manufacturer datasheet, helping engineers choose between standard PIC16F631 variants in the same PDIP-20 footprint.
Drop-in alternatives for PIC16F631-E/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 PIC16F631-E/P (same form factor and footprint) — differing in Package, RoHS Status, I/O Pins, Mounting Type, Instruction Execution Time.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F631-I/P
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC16F631-E/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$0.5927 / Unit
View Datasheet →PIC16F630-E/P
✅ Drop-In✓ In Stock
$1.22 / Unit
View Datasheet →PIC16F630-I/P
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC16F627A-I/P
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.72 / Unit
View Datasheet →PIC16F631-E/P Maximum Ratings & Electrical Characteristics
| Architecture | PIC16 mid-range 8-bit |
| Instruction Word Width | 14-bit |
| Program Memory (Flash) | 1.75 KB (1K x 14) |
| Data RAM | 64 bytes |
| Data EEPROM | 128 bytes |
| Maximum CPU Frequency | 20 MHz |
| Instruction Execution Time | 200 ns at 20 MHz |
| Operating Voltage Range | 2.0 V to 5.5 V |
| Operating Temperature Range (E grade) | -40 °C to +125 °C |
| I/O Pins | 12 |
| Timers | Timer0, Timer1 (16-bit, with dedicated oscillator) |
| Internal Oscillator | 8 MHz and 31 kHz LF-INTOSC |
| Package | PDIP-20 (300 mil) |
| Mounting Type | Through-Hole |
| MSL Level | 1 (unlimited floor life) |
| RoHS Status | Compliant (Pb-free per datasheet package code) |
| Flash Endurance | 100,000 erase/write cycles |
| EEPROM Endurance | 1,000,000 erase/write cycles |
| In-Circuit Programming | ICSP supported |
PIC16F631-E/P Pin Configuration
| Pin 1 | RA5/MCLR/VPP — Digital I/O / Master Clear reset (active low) / Programming voltage |
| Pin 2 | RA0/AN0/ULPWU/C12IN0- — Digital I/O / Analog channel 0 / Ultra-Low-Power Wake-Up / Comparator negative input |
| Pin 3 | RA1/AN1/C12IN1- — Digital I/O / Analog channel 1 / Comparator negative input |
| Pin 4 | RA2/AN2/CVREF/C12IN0+ — Digital I/O / Analog channel 2 / Comparator voltage reference / Comparator positive input |
| Pin 5 | RA3/AN3/C12IN1+/VREF+ — Digital I/O / Analog channel 3 / Comparator positive input / Voltage reference + |
| Pin 6 | RA4/AN4/T0CKI/C2OUT — Digital I/O / Analog channel 4 / Timer0 clock input / Comparator 2 output |
| Pin 7 | RC0/C12IN+ — Digital I/O / Comparator positive input |
| Pin 8 | VSS — Ground reference |
| Pin 9 | RC1/C12IN- — Digital I/O / Comparator negative input |
| Pin 10 | RC2/C11IN+ — Digital I/O / Comparator positive input |
| Pin 11 | VDD — Positive power supply (+2.0V to +5.5V) |
| Pin 12 | RC3/C11IN-/C12IN- — Digital I/O / Comparator negative inputs |
| Pin 13 | RC4/C11IN+ — Digital I/O / Comparator positive input |
| Pin 14 | RC5 — Digital I/O |
| Pin 15 | RC6 — Digital I/O |
| Pin 16 | RC7 — Digital I/O |
| Pin 17 | RB4/AN11 — Digital I/O with weak pull-up / Analog channel 11 (when applicable) |
| Pin 18 | RB5/AN10/CCP1 — Digital I/O with weak pull-up / Analog channel 10 / Capture-Compare-PWM 1 |
| Pin 19 | RB6/AN9/PGC — Digital I/O with weak pull-up / Analog channel 9 / ICSP clock (PGC) |
| Pin 20 | RB7/AN8/PGD — Digital I/O with weak pull-up / Analog channel 8 / ICSP data (PGD) |
Typical Applications
PIC16F631-E/P is suitable for 6 applications: Consumer Appliance Control, Industrial Sensor Signal Conditioning, Battery-Powered Remote Controls, LED Lighting Controller, Automotive Body Control Module, Low-Cost Hobbyist & Maker Projects.
Consumer Appliance Control
The PIC16F631-E/P is well suited for consumer appliance controllers - washing machines, microwave ovens, dishwashers - because its Extended -40C to +125C temperature grade handles under-cabinet heat. The 20MHz CPU clock executes control loops in under 1us, while 1.75KB Flash is sufficient for state-machine based user interfaces and sensor-driven cycle control. The integrated EEPROM (128B) stores user settings across power cycles. Placed near the appliance keypad with a 100nF ceramic bypass on VDD and a 4MHz external crystal, it replaces legacy 8051 designs with simpler programming and lower BOM cost.
Recommended
Industrial Sensor Signal Conditioning
Industrial sensor nodes benefit from the PIC16F631-E/P's integrated analog comparator for threshold detection on thermocouple, strain-gauge, and 4-20mA loops. The Extended -40C to +125C grade survives outdoor and cabinet environments. The 12-bit ADC option (in similar PIC16 family devices) and 20MHz CPU enable 10kHz sampling rates with on-chip averaging. Place the MCU adjacent to the sensor front-end, use the internal LF-INTOSC (31kHz) to wake periodically from nanoWatt sleep, and connect to a wired RS-485 transceiver (e.g. MCP2515) for bus connectivity.
Recommended
Battery-Powered Remote Controls
Battery-powered remote controls (TV, ceiling fans, garage openers) leverage the PIC16F631-E/P's nanoWatt sleep modes (down to nanoamp-level standby) and wide 2.0V-5.5V operating voltage to run directly from 2x AA cells. The 20MHz CPU wakes within microseconds to handle IR or RF transmissions. With 1.75KB Flash and 64B RAM, button matrix scanning and rolling-code algorithms fit easily. Connect to a 32.768kHz watch crystal on Timer1 for accurate timing, and use PORTA pins for the button matrix and PORTC for IR LED drive.
Recommended
LED Lighting Controller
LED lighting controllers (architectural strips, automotive interior lighting) use the PIC16F631-E/P's PWM capabilities on multiple pins and Extended temperature grade to drive high-current LED strings with thermal foldback. The 12 I/O pins drive RGBW channels, current-sense amplifiers, and a DMX-512 receiver (via external transceiver). At 20MHz, software PWM can dim with 8-bit resolution at 1kHz - adequate for theater-grade dimming. Place bulk capacitance near the MCU and use a separate LDO for the LED driver to keep noise out of the analog comparators.
Recommended
Automotive Body Control Module
Automotive body controllers (door modules, seat controllers, mirror adjusters) use the PIC16F631-E/P's Extended -40C to +125C temperature grade and 20-pin PDIP footprint for through-hole automotive PCB assemblies. The 12-bit ADC (in similar PIC16 family devices) reads wiper position and motor current. The integrated LIN-capable USART pairs with external LIN transceivers. For under-hood applications above +125C, designers prefer AEC-Q100 qualified parts like the PIC16F15323 - but for cabin/body use, the PIC16F631-E/P remains a cost-effective workhorse.
Recommended
Low-Cost Hobbyist & Maker Projects
Maker, hobbyist, and STEM education projects favor the PIC16F631-E/P because the PDIP-20 package is breadboard-friendly and the PICkit 3/4 programmer connects directly via ICSP (RB6/RB7). With 1.75KB Flash and 64B RAM, learners can implement ADC sampling, UART communication, and PWM motor control in Microchip's free MPLAB X IDE + XC8 compiler. The PIC16F631-E/P is a great teaching part: simple architecture, lots of application notes, and decades of community support. Pair with the Curiosity HPC development board for instant prototyping.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F631-E/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F631-I/P | PIC16F631-E/SO | PIC16F630-E/P | PIC16F630-I/P | PIC16F627A-I/P |
|---|---|---|---|---|---|---|
| Package | PDIP-20 | PDIP-20 | SOIC-20 | PDIP-20 | PDIP-20 | PDIP-20 |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 1.75 KB | 1.75 KB | 1.75 KB | 512 B (-71%) | 512 B (-71%) | 1.75 KB (different core) |
| RAM | 64 B | 64 B | 64 B | 64 B | 64 B | 224 B |
| EEPROM | 128 B | 128 B | 128 B | 64 B | 64 B | 128 B |
| Temperature Range | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +125C (Extended) | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +85C (Industrial) |
| Comparator Module | Yes (1 module) | Yes | Yes | No (omitted) | No (omitted) | Yes |
| Architecture / Core | PIC16 mid-range x14 (14-bit) | PIC16 mid-range x14 (14-bit) | PIC16 mid-range x14 (14-bit) | PIC16 mid-range x14 (14-bit) | PIC16 mid-range x14 (14-bit) | PIC16 enhanced mid-range x14 (different core) |
| Maximum CPU Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Pin Compatibility with PIC16F631-E/P | Reference | Yes (drop-in, temp grade only) | Yes (SOIC-20, footprint differs) | Yes (drop-in, reduced memory/peripherals) | Yes (drop-in, reduced memory/peripherals) | Partial - similar footprint, different core requires code rewrite |
Key Differentiators
- Extended -40C to +125C temperature grade versus I-grade competitors (vs PIC16F631-I/P)
- Integrated analog comparator module included (vs PIC16F630-E/P)
- PIC16 mid-range x14 standard core - drop-in code compatibility (vs PIC16F627A-I/P)
- Through-hole PDIP-20 for breadboard-friendly prototyping (vs PIC16F631-E/SO)
Design Notes
The PIC16F631-E/P nanoWatt Technology supports sleep currents down to the nanoamp range, but this requires careful pin configuration. Disable unused peripherals via the CMCON (comparator) and ANSEL (analog) registers, configure unused I/O as outputs driving low (not high-impedance inputs), and use the LF-INTOSC for low-power sleep timing. Estimated: disabling all peripherals and entering sleep at 3V typically yields < 1uA standby current, compared to ~5uA if modules are left enabled.
A common mistake is leaving analog pins configured as analog after the ADC is disabled - the analog input buffers consume several microamps even when the ADC is off. Always set the corresponding ANSEL bit to 0 (digital) when the analog function is unused. According to Microchip datasheet 40001262F, failing to switch ANSEL bits costs ~ 1-2uA per enabled analog pin in sleep. Also, the MCLR pin (pin 1) requires a 10-50kOhm pull-up to VDD for reliable operation - if you let MCLR float, the part may intermittently reset.
Place a 100nF ceramic decoupling capacitor within 5mm of the VDD pin (pin 11) and a bulk 10uF capacitor within 20mm. Keep analog traces (RA0-RA4, RC1-RC4) away from digital switching signals like PWM outputs to avoid coupling into the comparator module. Per Microchip application note AN2500, ground the ICSP pins (RB6/PGC pin 19, RB7/PGD pin 20) with low-impedance return paths for reliable in-circuit programming. For high-noise environments, place a ferrite bead on VDD and a 100nF cap on the MCU side.
The PIC16F631-E/P Extended (-40C to +125C) grade has the same junction temperature limits as the I-grade but is tested and qualified for sustained operation at +125C. In a sealed enclosure with limited airflow, derate the ambient temperature budget by 10-15C to account for self-heating of surrounding components. Estimated: at 20 MHz, the device dissipates roughly 25 mW at 5V (5mA x 5V), so self-heating is minimal (<2C rise) but adjacent power components (LDOs, drivers) can dominate.
Compliance Information
RoHS compliant per Microchip packaging code; Pb-free matte-tin plating on PDIP-20 leads. Not AEC-Q100 qualified - for AEC-Q100 automotive applications use PIC16F15323 or similar. REACH SVHC declaration per Microchip product page.
