PIC16F874AT-I/PT - 8-bit 20MHz MCU 7KB Flash 44-TQFP | Microchip
MPN: PIC16F874AT-I/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $11.2 | $11.20 |
| 10 | $10.05 | $100.50 |
| 100 | $8.92 | $892.00 |
| 500 | $7.85 | $3,925.00 |
| 1,000 | $6.95 | $6,950.00 |
PIC16F874AT-I/PT Overview
An 8-bit microcontroller (MCU) is a single-chip computer built around an 8-bit data path and a RISC instruction set; in the broader taxonomy it sits between 4-bit legacy controllers and 16/32-bit MCUs, and is typically classified as an embedded microcontroller, RISC MCU, CMOS FLASH-based MCU, and within Microchip's product hierarchy as a PIC16 mid-range family device. PIC16F87X devices use a 14-bit instruction word and 35 single-word instructions, with most instructions executing in a single 200 ns instruction cycle at 20 MHz, giving roughly 5 MIPS of throughput.
Key features distinguishing this part include self-programmability (allowing in-application FLASH updates), an ICD (In-Circuit Debug) interface, two on-chip analog comparators with programmable reference, a 10-bit ADC with up to 8 channels, 100K endurance FLASH, 1M endurance EEPROM, and a wide 2.0 V to 5.5 V operating voltage range (the 'F' family runs up to 5.5 V). The PIC16F874A family is upwards source-code compatible with PIC16C5X, PIC12CXXX, and PIC16C7X devices, simplifying migration from legacy designs.
Typical applications include industrial control panels, sensor signal conditioning nodes, low-power consumer devices, motor control front-ends, and battery-backed instruments where the integrated EEPROM, ADC, comparators, and serial peripherals reduce external component count. The wide operating range and on-chip debug also make it a strong fit for prototyping platforms and educational development kits.
When designing with this MCU, ensure decoupling is placed close to VDD/AVDD/VSS/AVSS, use the MSSP and USART pins according to the 44-pin TQFP pinout, and review the migration note: Microchip recommends the newer PIC16F18875 for new designs. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found on a single manufacturer datasheet page.
Drop-in alternatives for PIC16F874AT-I/PT — 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 PIC16F874AT-I/PT (same form factor and footprint) — differing in Package, Operating Temperature, Serial Interfaces, Timers, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F874A-I/ML
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$3.21 / Unit
View Datasheet →PIC16F874A-E/PT
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$7.45 / Unit
View Datasheet →PIC16F874AT-E/PT
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$5.7 / Unit
View Datasheet →PIC16F874AT-I/ML
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$4.77 / Unit
View Datasheet →PIC16F877AT-I/PT
✅ Drop-In✓ In Stock
$5.42 / Unit
View Datasheet →PIC16F874AT-I/PT Maximum Ratings & Electrical Characteristics
| Core | PIC16 (8-bit RISC, 14-bit instruction word) |
| Program Memory Type | FLASH |
| Program Memory Size | 7 KB (4K x 14 words) |
| Data RAM | 192 bytes |
| Data EEPROM | 128 bytes |
| Max CPU Speed | 20 MHz |
| Instruction Cycle Time | 200 ns |
| Operating Voltage | 2.0 V to 5.5 V |
| I/O Pins | 33 |
| ADC | 10-bit, up to 8 channels |
| Timers | 2 x 8-bit, 1 x 16-bit |
| Comparators | 2 analog comparators |
| Communication | MSSP (I2C/SPI), USART |
| Package | 44-pin TQFP (10x10 mm) |
| Operating Temperature | -40 C to +85 C (industrial) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC16F874AT-I/PT Pin Configuration
| Pin 1 | MCLR/VPP/THV — Master Clear (reset) input / programming voltage |
| Pin 2 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Pin 4 | RA2/AN2/Vref- — PORTA bit 2 / analog input 2 / ADC Vref- |
| Pin 5 | RA3/AN3/Vref+ — PORTA bit 3 / analog input 3 / ADC Vref+ |
| Pin 6 | RA4/T0CKI/C1OUT — PORTA bit 4 / Timer0 clock input / comparator 1 output |
| Pin 7 | RA5/AN4/SS/C2OUT — PORTA bit 5 / analog input 4 / SPI slave select / comparator 2 output |
| Pin 8 | RE0/RD/AN5 — PORTE bit 0 / parallel slave port read / analog input 5 |
| Pin 9 | RE1/WR/AN6 — PORTE bit 1 / parallel slave port write / analog input 6 |
| Pin 10 | RE2/CS/AN7 — PORTE bit 2 / parallel slave port chip select / analog input 7 |
| Pin 11 | VDD — Digital supply voltage |
| Pin 12 | VSS — Digital ground |
| Pin 13 | OSC1/CLKI — Oscillator input / external clock input |
| Pin 14 | OSC2/CLKO — Oscillator output / clock output |
| Pin 15 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 16 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 PWM/capture |
| Pin 17 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM/capture |
| Pin 18 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 19 | RD0/PSP0 — PORTD bit 0 / parallel slave port data 0 |
| Pin 20 | RD1/PSP1 — PORTD bit 1 / parallel slave port data 1 |
| Pin 21 | RD2/PSP2 — PORTD bit 2 / parallel slave port data 2 |
| Pin 22 | RD3/PSP3 — PORTD bit 3 / parallel slave port data 3 |
| Pin 23 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 24 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 25 | RC6/TX/CK — PORTC bit 6 / USART TX / USART clock |
| Pin 26 | RC7/RX/DT — PORTC bit 7 / USART RX / USART data |
| Pin 27 | RD4/PSP4 — PORTD bit 4 / parallel slave port data 4 |
| Pin 28 | RD5/PSP5 — PORTD bit 5 / parallel slave port data 5 |
| Pin 29 | RD6/PSP6 — PORTD bit 6 / parallel slave port data 6 |
| Pin 30 | RD7/PSP7 — PORTD bit 7 / parallel slave port data 7 |
| Pin 31 | VSS — Digital ground |
| Pin 32 | VDD — Digital supply voltage |
| Pin 33 | RB0/INT — PORTB bit 0 / external interrupt |
| Pin 34 | RB1 — PORTB bit 1 |
| Pin 35 | RB2 — PORTB bit 2 |
| Pin 36 | RB3/PGM — PORTB bit 3 / low-voltage programming |
| Pin 37 | RB4 — PORTB bit 4 |
| Pin 38 | RB5 — PORTB bit 5 |
| Pin 39 | RB6/PGC — PORTB bit 6 / ICD clock |
| Pin 40 | RB7/PGD — PORTB bit 7 / ICD data |
| Pin 41 | AVDD — Analog supply voltage |
| Pin 42 | AVSS — Analog ground |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC16F874AT-I/PT is suitable for 6 applications: Industrial Sensor Interface Module, Battery-Backed Instrument with EEPROM Logging, HMI Keypad / Display Controller, Motor Control Front-End (Brushed DC / Stepper), Smart Energy Meter / Sub-Metering, Educational Development / Prototyping Platform.
Industrial Sensor Interface Module
PIC16F874AT-I/PT is well suited to industrial sensor interface modules because it integrates a 10-bit ADC with up to 8 channels and 2 analog comparators alongside 33 digital I/O lines. Its 2.0 V to 5.5 V operating range and -40 C to +85 C industrial temperature rating allow direct deployment on 24 V-buck-derived 5 V or 3.3 V rails in factory automation. Compared with discrete op-amp plus ADC solutions, the PIC16F874A reduces BOM count by combining reference, mux, and MCU. USART plus MSSP enable Modbus RTU or SPI sensor backbones; the 7 KB FLASH accommodates calibration tables and linearization firmware.
Recommended
Battery-Backed Instrument with EEPROM Logging
The 128-byte on-chip data EEPROM provides 1M erase/write cycles of non-volatile storage, ideal for logging calibration constants, runtime hours, or fault codes in battery-backed instruments. The PIC16F874AT-I/PT's 192-byte RAM is sufficient for short circular buffers before committing to EEPROM, and the MSSP can interface external I2C EEPROM or FRAM for longer logs. A 20 MHz CPU keeps energy budget low by returning to sleep between samples; the wide 2.0 V to 5.5 V range supports single-cell Li-ion and 3 V coin-cell topologies alike.
Recommended
HMI Keypad / Display Controller
With 33 I/O and built-in USART, the PIC16F874AT-I/PT can scan a 4x4 matrix keypad and drive a character LCD or LED display while communicating upstream to a host controller via UART. The 200 ns instruction cycle keeps debounce and display-refresh latency low. Its self-programmability lets field firmware be updated through the USART boot path, useful for HMI modules shipped to remote sites. The 44-pin TQFP exposes enough pins to also drive a small TFT or segment LCD through external shift registers.
Recommended
Motor Control Front-End (Brushed DC / Stepper)
The CCP1 and CCP2 capture/compare/PWM modules, combined with the 16-bit timer and analog comparators, allow the PIC16F874AT-I/PT to generate PWM, sample back-EMF, and time commutations for brushed DC or unipolar stepper motors. Current sensing via the on-chip comparators reduces external analog front-end parts. The 20 MHz clock and 200 ns cycle are adequate for sub-microsecond PWM resolution at moderate RPM. Designers add external H-bridge drivers because the MCU's I/O cannot directly sink motor current.
Recommended
Smart Energy Meter / Sub-Metering
PIC16F874AT-I/PT integrates a 10-bit ADC and analog comparators to measure current via shunt or CT and to detect zero-crossing for power calculations in single-phase sub-meters. EEPROM endurance (1M cycles) is sufficient for cumulative energy counters stored across power cycles. The 7 KB FLASH holds calibration tables, and the USART/MSSP allows connection to a concentrator via RS-485 or I2C. Industrial temperature grade ensures reliability in service panels.
Recommended
Educational Development / Prototyping Platform
The PIC16F874AT-I/PT is widely used in university curricula and hobbyist prototyping because of its 35-instruction RISC core, in-circuit debug (ICD) support, and free MPLAB X + XC8 toolchain. Its 44-pin TQFP gives breadboard-friendly access through carrier boards, and the rich peripheral set (ADC, comparators, USART, MSSP) covers most introductory embedded labs. PIC16F18875 is the recommended migration target for new curricula, but the 874A remains in countless existing labs and textbooks.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F874AT-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F874A-I/ML | PIC16F874A-E/PT | PIC16F874AT-E/PT | PIC16F877AT-I/PT |
|---|---|---|---|---|---|
| Package | 44-TQFP (PT) 10x10 mm | 44-QFN (ML) 8x8 mm | 44-TQFP (PT) 10x10 mm | 44-TQFP (PT) 10x10 mm | 44-TQFP (PT) 10x10 mm |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| FLASH Program Memory | 7 KB | 7 KB | 7 KB | 7 KB | 14 KB |
| Data RAM | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 256 bytes |
| Data EEPROM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes |
| Max CPU Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| 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 | -40 C to +85 C | -40 C to +85 C | -40 C to +125 C | -40 C to +125 C | -40 C to +85 C |
| I/O Pins | 33 | 33 | 33 | 33 | 33 |
Key Differentiators
- Extended temperature grade option in same TQFP-44 footprint (vs PIC16F874A-E/PT)
- Doubles FLASH and RAM with identical peripheral set (vs PIC16F877AT-I/PT)
- Smaller footprint QFN-44 variant available for space-constrained designs (vs PIC16F874A-I/ML)
Design Notes
Place a 100 nF decoupling capacitor as close as possible to each VDD/VSS pair (pins 11/12 and 31/32), and add a 10 uF bulk capacitor on the AVDD/AVSS pair (pins 41/42) to keep ADC noise low. PIC16F874A can operate down to 2.0 V, but at 20 MHz the minimum guaranteed supply is 4.0 V per the datasheet DC characteristics; de-rate CPU clock for 3.3 V rails if the application requires full temperature range.
Use a 4-layer PCB with a continuous ground plane beneath the TQFP-44 footprint to minimize digital switching noise coupling into AVdd. Route the analog inputs AN0-AN7 and AVdd/AVss traces away from the parallel slave port (PORTD) and PWM outputs (CCP1/CCP2). Add a ferrite bead between VDD and AVDD if the analog and digital rails share the same supply, or use a separate LDO for the analog rail to maximize ADC SNR.
Configure unused I/O pins as outputs and tie them low, not high-impedance inputs, to avoid floating-pin supply current draw exceeding the datasheet maximum. Do not exceed the absolute maximum VDD of 7.5 V or current per pin of 25 mA. When using the ICD interface on RB6/RB7, ensure no strong pull-ups are placed on those pins since they share functions with PGC/PGD and the programmer will drive them.
For SPI communications above 2 MHz, keep the SCK/SDO/SDI traces shorter than 50 mm and place a 33 ohm series resistor near the driver to dampen reflections. The MSSP can operate up to FOSC/4 (5 MHz at 20 MHz FOSC); verify the slave device's timing budget before pushing the bus speed. For I2C, use 4.7 kohm pull-ups on SCL/SDA in standard mode and 2.2 kohm in fast mode (400 kHz).
Compliance Information
RoHS and lead-free per Microchip product page. Not AEC-Q100 qualified - automotive users should verify with Microchip or consider PIC16F874A-E/PT extended temp grade. Halogen-free status not stated in verified web data.