PIC16F631T-I/SO - 8-bit 20MHz 1.75KB Flash MCU | Microchip
MPN: PIC16F631T-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.18 | $1.18 |
| 10 | $1.05 | $10.50 |
| 100 | $0.92 | $92.00 |
| 500 | $0.82 | $410.00 |
| 1,000 | $0.74 | $740.00 |
PIC16F631T-I/SO Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, program memory (Flash/ROM), peripherals and I/O into one package, optimized for embedded control rather than high-throughput computation. Within the broader taxonomy, the PIC16F631 sits in the microcontroller -> embedded microcontroller -> low-pin-count MCU branch, sharing the standardized Microchip mid-range x14 instruction set with hundreds of other PIC16F variants. This shared ISA allows code developed for one PIC16F device to be ported across the family with minimal toolchain changes, accelerating firmware development for consumer, industrial and appliance designs.
Key feature highlights include a 20 MHz maximum CPU clock delivering 5 MIPS, 256 bytes of EEPROM data memory, an enhanced Capture/Compare/PWM (ECCP) module, two analog comparators, and a 10-bit ADC (the ADC count and comparator routing depend on package; on the 20-pin SO the device still exposes the full peripheral set internally). Internal oscillator accuracy plus an on-chip voltage reference simplify BOM cost by removing external crystals in many applications.
Architecturally, the device uses a 14-bit instruction word modified Harvard architecture with separate program Flash and data SRAM buses, allowing instruction fetch and data access in the same cycle. The nanoWatt feature set provides multiple idle and sleep modes, peripheral clock gating, and an ultra-low-power watchdog that lets deep-sleep current drop to tens of nA, making the part suitable for battery-powered sensor and metering endpoints.
Typical applications include home appliance control boards, battery chargers, LED lighting drivers, industrial sensor interfaces, remote controls, low-cost consumer electronics and white-goods user-interface modules where small footprint, low power and a stable peripheral set are more critical than raw CPU speed.
When designing in this part, pay attention to the maximum 20 MHz Fosc at 4.0V to 5.5V (operation below 4.0V is limited to lower Fosc), reserve one I/O pin for in-circuit serial programming (ICSP) using the ICSPDAT/ICSPCLK pair, and place a 0.1uF decoupling capacitor within 5 mm of VDD. The T-suffix and -I/-SO qualifiers indicate tape-and-reel packaging with industrial temperature grade.
This page consolidates distributor pricing, pin-compatible drop-in alternatives and practical design notes not aggregated in any single Microchip datasheet.
Drop-in alternatives for PIC16F631T-I/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 PIC16F631T-I/SO (same form factor and footprint) — differing in Package, ADC, Operating Temperature, Timers, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F631-I/SO
✅ Drop-In✓ In Stock
$1.28 / Unit
View Datasheet →PIC16F631-E/SO
✅ Drop-In✓ In Stock
$0.5927 / Unit
View Datasheet →PIC16F631T-I/ML
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$0.7 / Unit
View Datasheet →PIC16F630-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F616-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F631T-I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16F mid-range x14 (modified Harvard, 14-bit instruction word) |
| CPU Bit-Width | 8-bit |
| Maximum CPU Clock | 20 MHz (5 MIPS) |
| Program Flash Memory | 1.75 KB (1K x 14 words) |
| Data SRAM | 64 bytes |
| Data EEPROM | 256 bytes |
| Operating Voltage (VDD) | 2.0 V to 5.5 V |
| I/O Pins | 18 bidirectional |
| ADC | On-chip (channels vary by package); see datasheet |
| Comparators | 2 on-chip analog comparators |
| Timers | Timer0, Timer1, Timer2 + 1 ECCP/SCCP module |
| Package | 20-pin SOIC (SO), 7.50 mm body width |
| Operating Temperature | -40 C to +85 C (industrial grade, -I suffix) |
| Mounting Type | Surface Mount (SOIC) |
| Programming | ICSP (In-Circuit Serial Programming) via ICSPCLK/ICSPDAT |
| Power-Saving Modes | nanoWatt Technology: idle, sleep, watchdog disable |
| RoHS Status | Compliant (per Microchip product family) |
PIC16F631T-I/SO Pin Configuration
| Pin 1 | VDD — Positive supply voltage (2.0 V to 5.5 V) |
| Pin 2 | RA5/T1CKI/OSC1/CLKIN — I/O RA5 / Timer1 clock input / crystal oscillator input / external clock input |
| Pin 3 | RA4/T1G/OSC2/CLKOUT — I/O RA4 / Timer1 gate / crystal oscillator output / Fosc/4 output |
| Pin 4 | RA3/MCLR/VPP — I/O RA3 / Master Clear (reset, active-low) / programming voltage |
| Pin 5 | RA2/AN2/T0CKI/INT — I/O RA2 / analog input 2 / Timer0 clock / external interrupt |
| Pin 6 | RA1/AN1/C1IN-/ICSPCLK — I/O RA1 / analog input 1 / comparator input / ICSP clock |
| Pin 7 | RA0/AN0/C1IN+/ICSPDAT — I/O RA0 / analog input 0 / comparator input / ICSP data |
| Pin 8 | VSS — Ground reference |
| Pin 9 | RA7/OSC1/CLKI — I/O RA7 / crystal oscillator input / external clock input |
| Pin 10 | RA6/OSC2/CLKO — I/O RA6 / crystal oscillator output / clock output |
| Pin 11 | RC5/CCP1/P1A — I/O RC5 / Capture-Compare-PWM 1 / PWM output |
| Pin 12 | RC4/C2OUT — I/O RC4 / Comparator 2 output |
| Pin 13 | RC3/C12IN3-/AN7 — I/O RC3 / comparator input / analog input 7 |
| Pin 14 | RC2/C12IN2-/AN6 — I/O RC2 / comparator input / analog input 6 |
| Pin 15 | RC1/C12IN1-/AN5 — I/O RC1 / comparator input / analog input 5 |
| Pin 16 | RC0/C12IN0+/AN4 — I/O RC0 / comparator input / analog input 4 |
| Pin 17 | RC7/C1OUT — I/O RC7 / Comparator 1 output |
| Pin 18 | RC6 — I/O RC6 |
| Pin 19 | RB7 — I/O RB7 |
| Pin 20 | RB6 — I/O RB6 |
Typical Applications
PIC16F631T-I/SO is suitable for 6 applications: Home Appliance Control Boards, Battery-Powered Sensor Nodes, LED Lighting Drivers, Consumer Remote Controls, Industrial Sensor Interfaces, White-Goods User-Interface Modules.
Home Appliance Control Boards
The PIC16F631T-I/SO fits home appliance control boards (washing machines, microwave ovens, dishwashers) because of its 20 MHz core, 18 I/O pins and on-chip comparators which directly drive triac and relay control loops. Placing the MCU between the user-interface keypad and the appliance main relay lets firmware debounce keys, sequence pumps/heaters and monitor safety sensors in real time at 5 MIPS. The industrial -40C to +85C temperature grade survives the kitchen thermal environment, while nanoWatt sleep modes reduce standby power below 1 uA when the appliance is idle.
Recommended
Battery-Powered Sensor Nodes
The PIC16F631T-I/SO is well matched to battery-powered wireless sensor nodes and remote metering applications because its nanoWatt sleep modes drop quiescent current to a few tens of nanoamperes. Operating directly from a 2.0 V to 5.5 V supply lets the MCU run from a single Li-ion cell, two alkaline AAs or a small Li-SOCl2 primary battery without a boost regulator. The 18 I/O pins interface easily to SPI or I2C sensors, and the on-chip comparators can wake the part on analog threshold events, extending battery life in remote-deployed systems.
Recommended
LED Lighting Drivers
The PIC16F631T-I/SO drives cost-sensitive LED lighting fixtures by combining a 20 MHz core for PWM dimming with two on-chip analog comparators for current sensing. A single MCU can produce three software-PWM channels at 1 kHz with 10-bit equivalent resolution, sufficient for ambient white-light dimming and color-mixing designs. The wide 2.0 V to 5.5 V supply window lets the MCU share a regulator with the LED string driver, simplifying the BOM in retrofit lamp modules and architectural lighting strips.
Recommended
Consumer Remote Controls
The PIC16F631T-I/SO suits infrared and RF remote control handsets thanks to its 18 I/O pins for key-scanning matrices, low-power sleep modes that extend coin-cell battery life, and accurate on-chip oscillator that locks IR carrier frequency without a crystal. The 20 MHz CPU handles RC5, NEC or proprietary IR protocols with timing margins under 5%. Combined with the small 20-pin SOIC outline, the part fits behind the keypad of handheld TV, set-top-box and smart-home remote controllers.
Recommended
Industrial Sensor Interfaces
The PIC16F631T-I/SO functions as an industrial sensor-interface or signal-conditioning front-end by leveraging its two on-chip analog comparators, 18 I/O lines and industrial -40C to +85C operating range. The comparators can implement window comparators for limit-switch or proximity-sensor inputs, while the I/O pins drive optocouplers or 4-20 mA loop interfaces. The 20-pin SOIC is robust for through-hole adapter boards used in panel installations, and the wide 2.0 V to 5.5 V VDD supports 24 V loop-powered designs with a simple LDO.
Recommended
White-Goods User-Interface Modules
The PIC16F631T-I/SO powers user-interface modules on washing machines, refrigerators and ovens by combining enough I/O for 7-segment or matrix displays, push-button scanning and status-LED multiplexing. The PIC16F mid-range instruction set is well supported by MPLAB X IDE and XC8 compiler, accelerating UI firmware development. Operating from 2.0 V to 5.5 V allows the module to share a 5 V supply with display drivers, while nanoWatt idle modes cut standby power when the appliance is in display-dim or sleep mode.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F631T-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F631-I/SO | PIC16F631-E/SO | PIC16F630-I/SO | PIC16F616-I/SO |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 20-pin SOIC | 20-pin SOIC - same | 20-pin SOIC - same | 20-pin SOIC - same | 20-pin SOIC - same |
| Program Flash | 1.75 KB (1K x 14) | 1.75 KB (1K x 14) | 1.75 KB (1K x 14) | 0.875 KB (512 x 14) -50% | 3.5 KB (2K x 14) +100% |
| SRAM | 64 bytes | 64 bytes | 64 bytes | 64 bytes | 128 bytes +100% |
| EEPROM | 256 bytes | 256 bytes | 256 bytes | 128 bytes -50% | 256 bytes |
| Maximum Fosc | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| I/O Pins | 18 | 18 | 18 | 12 -33% | 18 |
| Operating Voltage | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V |
| Operating Temperature | -40C to +85C (industrial) | -40C to +85C | -40C to +125C (extended) | -40C to +85C | -40C to +85C |
| Analog Comparators | 2 | 2 | 2 | 1 -50% | 2 |
Key Differentiators
- Same die and pinout as PIC16F631 family - true drop-in (vs PIC16F630-I/SO)
- Industrial temperature grade with -40C to +85C rating (vs PIC16F631T-I/ML (QFN))
- nanoWatt sleep current below 50 nA typical (vs PIC16F616-I/SO)
Design Notes
Place a 0.1uF decoupling capacitor within 5 mm of the VDD pin (pin 1) and a bulk capacitor (e.g. 10uF) at the board-level supply. The PIC16F631T-I/SO draws up to ~10 mA active at 20 MHz and 5 V, with nanoWatt sleep current around 50 nA typical. Decoupling is essential for ADC accuracy and stable POR behavior across the 2.0 V to 5.5 V operating window. Estimated: 5 V x 10 mA = 50 mW active dissipation.
Reserve one I/O pin pair for In-Circuit Serial Programming: ICSPCLK on RA1 (pin 6) and ICSPDAT on RA0 (pin 7). Do not place series resistors above ~100 ohm on these pins, as they can interfere with the programming voltage on MCLR/VPP (pin 4). A 10 kohm pull-up on MCLR is recommended for clean resets; for production programming, route the ICSP header to a standard 6-pin RJ-style or Tag-Connect footprint.
Maximum Fosc of 20 MHz is only valid above 4.0 V VDD; below 4.0 V the Fosc must be derated (e.g. 10 MHz at 3.3 V). Configuration-word settings (CONFIG) control watchdog enable, brownout voltage and code protection - these cannot be reprogrammed once code-protected without a bulk erase. Always verify the configuration bits in MPLAB X before mass programming and keep a known-good programming image in version control.
Keep analog signals (AN0-AN7, C1IN-, C2IN-, etc.) routed away from the OSC1/OSC2 crystal traces and high-current switching nodes to minimize noise coupling into the ADC and comparators. Use a guard ring around analog inputs when sampling low-impedance signals below 100 mV. Place the optional external crystal within 5 mm of OSC1/OSC2 with short symmetric traces to avoid oscillator startup failures at cold temperatures.
Compliance Information
RoHS and REACH compliance per Microchip product family declarations. Standard PIC16F631 variants are not AEC-Q100 qualified; for automotive designs use the PIC16F631-E/SO extended temperature grade or consult the Microchip automotive product line. Lead-free and halogen-free packaging per Microchip packaging specifications.
