PIC16LF628AT-I/SO - 8-Bit 20MHz MCU, 3.5KB FLASH, 18-SOIC | Microchip
MPN: PIC16LF628AT-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.61 | $26.10 |
| 100 | $2.32 | $232.00 |
| 500 | $2.08 | $1,040.00 |
| 1,000 | $1.86 | $1,860.00 |
| 3,000 | $1.62 | $4,860.00 |
PIC16LF628AT-I/SO Overview
An 8-bit microcontroller (MCU) is a programmable integrated circuit that integrates a CPU core, non-volatile program memory, volatile data memory, and configurable I/O peripherals onto a single silicon die. 8-bit MCUs occupy the entry-level tier of the embedded computing hierarchy - above fixed-function logic ICs but below 32-bit microcontrollers in arithmetic throughput. Within the PIC16 family specifically, the LF628A sits in the mid-range (14-bit instruction word) PIC16 tier, positioned between the smaller PIC12/PIC16F84A legacy parts and the more modern PIC16F1xxx enhanced mid-range devices. Its RISC-based Harvard architecture executes most instructions in a single clock cycle, giving it competitive code density per MHz compared with traditional CISC 8-bit cores.
Key features include 16 I/O pins with individually configurable direction registers, an integrated 4 MHz internal oscillator (calibrable), two 8-bit timers plus one 16-bit timer, a 10-bit ADC-free analog comparator block, a USART for serial communication, and Microchip's nanoWatt Technology for sleep currents below 1 uA. The device supports in-circuit serial programming (ICSP) via two pins, enabling firmware updates without removing the part from the PCB. Code protection lock bits prevent unauthorized memory reads, and the watchdog timer with its own on-chip RC oscillator provides an independent recovery mechanism for software lockups.
Typical applications include low-cost consumer appliance controllers, battery-powered remote sensors, hobbyist and educational development platforms, simple motor control loops, LED drivers, and replacement of legacy 8051 or PIC16F84A designs. The wide voltage range and nanoWatt sleep modes also support energy-harvesting designs where quiescent current directly determines battery life. Industrial designers favor the part for its long-term Microchip supply commitment and its mature, well-documented toolchain (MPLAB X, XC8 compiler, PICKit programmers).
When designing with this part, observe the absolute maximum Vdd of 5.5V - exceeding this rating destroys the part. Use 100 nF decoupling within 5 mm of the Vdd pin and place the MCLR pull-up (typically 10 kohm) close to the pin to avoid spurious resets. The internal oscillator is factory-calibrated to within 1% of nominal, but for UART timing above 9600 baud, select the crystal oscillator mode and provide a 4x or higher baud-rate crystal. This page synthesizes current distributor pricing, drop-in same-package alternatives, and design considerations that the manufacturer datasheet alone does not provide.
Drop-in alternatives for PIC16LF628AT-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 PIC16LF628AT-I/SO (same form factor and footprint) — differing in Package, Timers, Communication, Core Architecture, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LF628A-I/SO
✅ Drop-In✓ In Stock
$2.21 / Unit
View Datasheet →PIC16LF628-04I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF627A-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.65 / Unit
View Datasheet →PIC16LF648A-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.3 / Unit
View Datasheet →PIC16F628A-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.32 / Unit
View Datasheet →PIC16LF628AT-I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC RISC, 8-bit, 14-bit instruction word (mid-range) |
| Family | PIC16F |
| Program Memory (Flash) | 3.5 KB (2K x 14) |
| Data EEPROM | 128 bytes |
| SRAM | 224 bytes |
| Maximum CPU Frequency | 20 MHz |
| Operating Voltage (Vdd) | 2.0 V to 5.5 V |
| I/O Pins | 16 |
| Timers | 2 x 8-bit + 1 x 16-bit (TMR0/TMR1/TMR2) |
| Analog Peripherals | 2 comparators (no ADC) |
| Communication | USART (SCI/SPI master) |
| Internal Oscillator | 4 MHz (factory-calibrated) |
| Watchdog Timer | Yes (independent on-chip RC) |
| ICSP (In-Circuit Serial Programming) | Yes |
| Brown-out Reset | Yes |
| Power-Saving Modes | nanoWatt Technology (sleep < 1 uA typical) |
| Operating Temperature | -40C to +85C (industrial) |
| Package | 18-SOIC (SOIC-18 wide, 7.5 mm body) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited floor life at <30C/85% RH) |
| Lead-Free / RoHS | Yes - lead-free finish, RoHS compliant |
PIC16LF628AT-I/SO Pin Configuration
| Pin 1 | RA2/AN2/CVREF — GPIO RA2 / analog comparator input 2 / CVREF output |
| Pin 2 | RA3/AN3/C1OUT — GPIO RA3 / analog comparator input 3 / comparator 1 output |
| Pin 3 | RA4/T0CKI/C2OUT — GPIO RA4 / Timer0 clock input / comparator 2 output (open-drain) |
| Pin 4 | MCLR/VPP — Master clear reset (active-low) / programming voltage input |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — GPIO RB0 / external interrupt input |
| Pin 7 | RB1/RX/DT — GPIO RB1 / USART RX / synchronous data |
| Pin 8 | RB2/TX/CK — GPIO RB2 / USART TX / synchronous clock |
| Pin 9 | RB3/CCP1 — GPIO RB3 / Capture/Compare/PWM 1 output |
| Pin 10 | RB4/PGM — GPIO RB4 / ICSP programming clock (low-voltage programming) |
| Pin 11 | RB5/EN — GPIO RB5 / ICSP programming enable |
| Pin 12 | RB6/PGC — GPIO RB6 / ICSP serial clock (always clock pin) |
| Pin 13 | RB7/PGD — GPIO RB7 / ICSP serial data |
| Pin 14 | VDD — Positive power supply (2.0V-5.5V) |
| Pin 15 | OSC2/CLKOUT/RA6 — Crystal oscillator output / Fosc/4 clock output / GPIO RA6 |
| Pin 16 | OSC1/CLKIN/RA7 — Crystal oscillator input / external clock input / GPIO RA7 |
| Pin 17 | RA0/AN0 — GPIO RA0 / analog comparator input 0 |
| Pin 18 | RA1/AN1 — GPIO RA1 / analog comparator input 1 |
Typical Applications
PIC16LF628AT-I/SO is suitable for 6 applications: Battery-Powered Remote Sensor Nodes, Consumer Appliance Control Boards, Hobbyist and Educational Development Platforms, LED Lighting and Dimmer Controllers, Legacy Industrial Control Replacement, Serial Protocol Bridges and Adapters.
Battery-Powered Remote Sensor Nodes
The PIC16LF628AT-I/SO is well-suited for battery-powered remote sensor nodes because its nanoWatt sleep current is below 1 uA typical at 3V, allowing years of operation from a single CR2032 cell. The integrated 4 MHz internal oscillator eliminates the standby current of an external crystal, and the 16 I/O pins easily accommodate a sensor plus a low-power RF link driver. With 3.5 KB of flash and 224 bytes of SRAM, the part can run a periodic-measurement-and-transmit firmware loop with simple averaging and thresholding algorithms. The wide 2.0V-5.5V operating range lets the design survive battery discharge down to 2V without brown-out reset. Compared to a discrete 555-timer + op-amp sensing circuit, the PIC16LF628AT-I/SO provides programmable behavior, in-field firmware updates via ICSP, and EEPROM storage for calibration constants.
Recommended
Consumer Appliance Control Boards
In consumer appliances such as microwave ovens, washing machines, and coffee makers, the PIC16LF628AT-I/SO provides 16 I/O pins sufficient for keypad scanning, relay drivers, status LEDs, and a USART link to a higher-end main controller or display board. The 3.5 KB flash comfortably fits typical appliance control code including timing loops, beep patterns, and safety interlock checks. Industrial temperature rating (-40C to +85C) covers under-cabinet and laundry-room environments, and the 25 mA per-pin source/sink can drive optocouplers and small relays directly without external buffers. Compared to mechanical timers and discrete logic, the PIC16LF628AT-I/SO enables feature differentiation through firmware alone, eliminating costly BOM changes between product variants. Microchip's 25-year supply commitment on this mature part makes it suitable for long-lifecycle consumer products.
Recommended
Hobbyist and Educational Development Platforms
The PIC16LF628AT-I/SO is a popular choice in hobbyist and educational settings because of its mature documentation, free MPLAB X IDE, and low-cost PICKit programmers. With 3.5 KB flash and a 20 MHz CPU, it can run introductory projects such as blinking LEDs, PWM motor control, UART communication with a PC terminal, and I2C master mode using software bit-banging - a complete embedded-systems curriculum topic list. The internal 4 MHz oscillator allows prototypes to operate without any external components, while still providing a 4x clock-rate headroom for time-sensitive applications. Compared to Arduino Uno's ATmega328P, the PIC16LF628AT-I/SO is smaller, cheaper, and offers the educational benefit of configuring registers directly without high-level library abstractions. Source code examples are widely available in C and assembly on Microchip's developer help documentation.
Recommended
LED Lighting and Dimmer Controllers
For simple LED lighting and dimmer applications, the PIC16LF628AT-I/SO provides the PWM output capability needed for brightness control of LED strings and DC motor speed regulation. The 16-bit TMR1 plus 8-bit TMR2 can generate complementary PWM signals for half-bridge drivers, and the two analog comparators enable zero-cross detection of AC mains for phase-angle dimming of incandescent or dimmable LED loads. With 3.5 KB flash, the firmware can implement dimming curves, soft-start, and thermal foldback algorithms. The wide 2.0V-5.5V range supports battery-powered LED strips (3V-4.5V lithium) as well as 5V USB-LED fixtures. Compared to a dedicated LED-driver IC like the TLC5940, the PIC16LF628AT-I/SO adds general-purpose I/O and USART for networked lighting systems while sacrificing some PWM resolution.
Recommended
Legacy Industrial Control Replacement
The PIC16LF628AT-I/SO serves as a form-fit-function replacement for obsolete PIC16F84A and PIC16C84 designs in legacy industrial controllers where PCB layout cannot be redrawn. Although the PIC16LF628AT-I/SO is not pin-compatible with PIC16F84A (different pin assignments), it shares the same SOIC-18 package outline and offers 4x more flash plus the comparator peripheral. For genuinely pin-compatible modern replacements within the PIC16F family, the PIC16F628A-I/SO is the standard drop-in. Compared to redesigning with a modern 32-bit MCU like the STM32F0 or PIC32MM, the PIC16LF628AT-I/SO allows firmware-only modernization, reducing time-to-market and re-certification costs. The part is also commonly used as a quick-turnaround EMC compliance fix: if an older design fails EMC, swapping in a newer PIC revision with better power-rail stability often resolves emissions issues.
Recommended
Serial Protocol Bridges and Adapters
The PIC16LF628AT-I/SO's integrated USART and flexible I/O pin assignment make it a common choice for low-cost serial protocol bridges - converting between UART and other serial interfaces such as SPI master, bit-banged I2C, or one-wire. With 3.5 KB of flash, the firmware can implement protocol translation, command parsing, and small FIFO buffers for rate adaptation between buses of different speeds. The wide operating voltage (2.0V-5.5V) allows the bridge to operate in either 3.3V or 5V domains. Compared to dedicated protocol-converter ICs (e.g., SC18IS602 for SPI-to-I2C), the PIC16LF628AT-I/SO is significantly cheaper and far more flexible, at the cost of requiring firmware development. A typical use case is a UART-to-DMX512 bridge for stage lighting control, or a UART-to-Modbus bridge for connecting legacy sensors to modern PLC systems.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LF628AT-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LF628A-I/SO | PIC16LF628-04I/SO | PIC16LF627A-I/SO | PIC16LF648A-I/SO | PIC16F628A-I/SO |
|---|---|---|---|---|---|---|
| Package | 18-SOIC (SOIC-18 wide) | 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 |
| Flash Program Memory | 3.5 KB (2K x 14) | 3.5 KB | 3.5 KB | 1.75 KB (-50%) | 7 KB (+100%) | 3.5 KB |
| Max CPU Frequency | 20 MHz | 20 MHz | 4 MHz (-80%) | 20 MHz | 20 MHz | 20 MHz |
| Operating Voltage Range | 2.0V to 5.5V | 2.0V to 5.5V | 2.0V to 5.5V | 2.0V to 5.5V | 2.0V to 5.5V | 3.0V to 5.5V (no 2V operation) |
| SRAM | 224 bytes | 224 bytes | 224 bytes | 128 bytes (-43%) | 256 bytes (+14%) | 224 bytes |
| EEPROM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 256 bytes | 128 bytes |
| I/O Pins | 16 | 16 | 16 | 16 | 16 | 16 |
| Packaging Format | Tape & Reel ('T' suffix) | Tube (no 'T' suffix) | Tube | Tube | Tube | Tube |
| Pricing Tier (qty 1) | $2.85 | $2.85 | $2.65 (-7%) | $2.40 (-16%) | $3.05 (+7%) | $2.95 (+4%) |
Key Differentiators
- Same-die drop-in alternative in tube packaging (vs PIC16LF628A-I/SO)
- Lower-cost downgrade with same package and 80% pin compatibility (vs PIC16LF628-04I/SO)
- Memory-upgraded sibling in same SOIC-18 footprint (vs PIC16LF648A-I/SO)
Design Notes
Estimated: at 5V Vdd, 20 MHz active mode with all I/O unloaded, the PIC16LF628AT-I/SO draws approximately 10 mA active current. At 3.3V and 4 MHz internal oscillator, expect 1.5 mA active. Sleep current is below 1 uA typical at 3V with WDT disabled. For battery designs, place a 100 nF decoupling capacitor within 5 mm of the Vdd pin (pin 14) and a 10 uF bulk capacitor if the supply trace exceeds 50 mm. Use a low-ESR ceramic (X7R); electrolytic capacitors degrade the high-frequency PSRR of the internal regulator.
Place the MCLR pull-up resistor (10 kohm typical) within 3 mm of pin 4 to prevent spurious resets from injection of noise. If ICSP programming is required, also place a series resistor (typically 10 kohm) between MCLR and the rest of the reset network so the programmer can pull MCLR low without contention. Route the ICSP PGC/PGD traces (pins 12-13) as short as possible and away from switching signals; long ICSP traces increase programming errors. Use a 4-layer PCB with a continuous ground plane under the MCU to reduce EMI emissions from the 20 MHz clock harmonics.
Do NOT confuse the PIC16LF628AT-I/SO with the PIC16F84A-I/SO: they share the SOIC-18 outline but have DIFFERENT pin assignments. A common pitfall is migrating an old PIC16F84A design assuming pin compatibility - the firmware and PCB must be redesigned. Another pitfall: the 'LF' (low-voltage) and 'F' (standard) variants have different Vdd ranges - the 'F' variant requires at least 3.0V and may fail to start on a depleted 3V lithium battery that the 'LF' variant can still operate from. Always verify the exact suffix when ordering.
When using the internal 4 MHz oscillator for UART communication, the factory calibration is accurate to within 1% but may drift with temperature and Vdd. For UART baud rates above 9600 baud, the receiver's allowable timing error of +/- 2% is easily exceeded by the uncalibrated internal oscillator plus temperature drift. Recommendation: use an external 4 MHz or 11.0592 MHz crystal in HS oscillator mode for any UART link above 9600 baud, or implement auto-baud-detection firmware. For RC oscillator mode (pin 15/16 as GPIO), add a 5 pF-50 pF capacitor to ground on OSC1 to slow the oscillator into a stable range.
Compliance Information
Lead-free matte-tin finish per Microchip product page; RoHS and REACH compliant per DigiKey product attributes. AEC-Q100 not applicable - this is a commercial/industrial-grade MCU; automotive designs should use the PIC16F628A-E/SO extended-temperature variant or PIC16F1823-I/SO automotive qualified parts.
