PIC16F628T-04I/SO - 4MHz 3.5KB Flash 8-bit MCU | Microchip
MPN: PIC16F628T-04I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.56 | $25.60 |
| 100 | $2.28 | $228.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.82 | $1,820.00 |
PIC16F628T-04I/SO Overview
A PIC (Peripheral Interface Controller) microcontroller is a Harvard-architecture RISC MCU whose program and data buses are separate, allowing a single instruction cycle per fetch. PIC16 mid-range devices such as the PIC16F628 belong to Microchip's flagship 8-bit family, which is the immediate successor to the PIC12 baseline family and a smaller-footprint alternative to the PIC18 enhanced family. Within the broader semiconductor hierarchy, the PIC16F628 sits in the Microcontrollers category under Integrated Circuits.
Key features include Power-on Reset (POR), Power-up Timer (PWRT), Oscillator Start-up Timer (OST), Brown-out Detect (BOD), Watchdog Timer (WDT) with its own on-chip RC oscillator, and programmable weak pull-ups on PORTB. The capture/compare/PWM (CCP) module, USART, and internal 4 MHz oscillator give the part enough peripherals to replace older PIC16C62x OTP designs with a single flash-erasable drop-in.
The PIC16F628A revision supersedes the PIC16F628 with twice the program memory (3.5KB vs 1.75KB), 224 bytes of RAM, and an internal comparator module, while preserving pin compatibility in SO, SS, and P packages. The "T" suffix in the orderable part number indicates tape-and-reel packing, and "/SO" specifies the 18-pin wide-body SOIC.
Typical applications include appliance control, hobby/robotics boards, low-end sensor front-ends, LED lighting sequencers, and replacement upgrades of legacy PIC16C-series designs. The on-chip EEPROM and internal oscillator eliminate two external components that would otherwise be required by older PICs.
When designing with this part, ensure the input voltage stays within 3.0V to 5.5V and choose the -04 speed grade (4 MHz) versus the -20 grade (20 MHz) based on firmware timing requirements. The 18-pin SOIC wide footprint requires standard SOIC-18 land pattern - the part is not pin-compatible with 14-pin SO PIC16F84 designs.
This page synthesizes distributor pricing from DigiKey/Mouser, drop-in alternatives within the PIC16F62x family, and practical design notes that go beyond the Microchip datasheet. All pricing is listed as of 2026-09-21.
Drop-in alternatives for PIC16F628T-04I/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 PIC16F628T-04I/SO (same form factor and footprint) — differing in Package, Operating Temperature, Analog Comparators, Internal Oscillator, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F628-04I/SO
✅ Drop-In✓ In Stock
$2.3 / Unit
View Datasheet →PIC16F628T-04/SO
✅ Drop-In✓ In Stock
$2.2 / Unit
View Datasheet →PIC16F628A-I/SO
✅ Drop-In✓ In Stock
$2.32 / Unit
View Datasheet →PIC16F628AT-I/SO
✅ Drop-In✓ In Stock
$1.92 / Unit
View Datasheet →PIC16F627-04I/SO
✅ Drop-In✓ In Stock
$1.59 / Unit
View Datasheet →PIC16F628-20I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F88-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F628T-04I/SO Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit Microcontroller (MCU) |
| Core Architecture | PIC16 mid-range RISC (Harvard) |
| Program Memory | 3.5KB (2K x 14) Flash |
| RAM | 224 bytes |
| EEPROM | 128 bytes |
| Maximum CPU Frequency | 4 MHz (-04 speed grade) |
| Supply Voltage (VDD) | 3.0 V to 5.5 V |
| I/O Pins | 16 (PORTA[5] + PORTB[8] + PORTA additional) |
| I/O Ports | 11 (per chipdig listing summary) |
| Analog Comparators | 2 (with programmable VREF module) |
| Timers | TMR0, TMR1, TMR2 with WDT |
| Brown-out Detect | Yes (BOD) |
| Power-on Reset | Yes (POR) |
| Operating Temperature | -40C to +85C (industrial, "I" grade) |
| Package | 18-pin SOIC (SO, wide-body 0.300 inch, 7.50 mm) |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel ("T" suffix) |
| RoHS Status | Compliant (Lead-Free / Pb-Free) |
| MSL Level | 1 (per JEDEC J-STD-020) |
PIC16F628T-04I/SO Pin Configuration
| Pin 1 | RA0/AN0 — Digital I/O / analog comparator 1 inverting input |
| Pin 2 | RA1/AN1 — Digital I/O / analog comparator 2 inverting input |
| Pin 3 | RA2/AN2/VREF — Digital I/O / VREF output for comparators |
| Pin 4 | RA3/AN3/CMP1 — Digital I/O / comparator 1 non-inverting input |
| Pin 5 | RA4/TOCKI/CMP2 — Digital I/O / TMR0 clock / comparator 2 output |
| Pin 6 | RA5/AN4 — Digital I/O / analog comparator non-inverting input |
| Pin 7 | RA6/OSC2/CLKOUT — Digital I/O / crystal output / Fosc output |
| Pin 8 | RA7/OSC1/CLKIN — Digital I/O / crystal input / external clock input |
| Pin 9 | RA8/MCLR/VPP — Master Clear reset input / programming voltage |
| Pin 10 | VDD — Positive supply (3.0V to 5.5V) |
| Pin 11 | VSS — Ground reference |
| Pin 12 | RB0/INT — Digital I/O / external interrupt |
| Pin 13 | RB1 — Digital I/O |
| Pin 14 | RB2 — Digital I/O |
| Pin 15 | RB3/PGM — Digital I/O / LVP programming entry |
| Pin 16 | RB4 — Digital I/O with interrupt-on-change |
| Pin 17 | RB5 — Digital I/O with interrupt-on-change |
| Pin 18 | RB6/TX/CK — Digital I/O / USART TX / ICSP clock |
Typical Applications
PIC16F628T-04I/SO is suitable for 6 applications: Appliance Control Boards, Hobby / Educational Robotics, LED Lighting Sequencers and Chasers, Sensor Front-End / Data Acquisition Nodes, Legacy PIC16C62x Replacement / Modernization, Industrial Control Logic Replacement.
Appliance Control Boards
The PIC16F628T-04I/SO fits appliance controllers (washing machines, microwave ovens, dishwashers) thanks to its 16 high-current I/O pins capable of direct LED and relay drive, plus on-chip EEPROM for nonvolatile cycle settings. With 3.5KB of flash and 128 bytes of EEPROM, the part stores user preferences, fault logs, and timer setpoints without an external memory chip. The CCP module generates the PWM needed for valve or motor control, while the two analog comparators monitor sensor thresholds for over-temperature or water-level detection. Industrial temperature grade (-40C to +85C) tolerates the thermal environment inside an unvented appliance housing.
Recommended
Hobby / Educational Robotics
The PIC16F628T-04I/SO is a favorite in hobby robotics because its 4 MHz internal oscillator needs no external crystal, freeing both RA6 and RA7 as I/O. The CCP module outputs servo PWM directly, and the 16 I/O pins can drive a small robot's sensors, LEDs, and motor bridges. Flash-based program memory (vs OTP on PIC16C devices) means beginners can re-flash mistakes hundreds of times. Programming via ICSP using a PICkit 3/5 lets students debug in-circuit from the MPLAB X IDE.
Recommended
LED Lighting Sequencers and Chasers
The PIC16F628T-04I/SO drives up to 16 LEDs directly via its high-current sink/source I/O (25 mA per pin, 200 mA total), enough for chaser, marquee, and decorative lighting strips without external drivers. The internal 4 MHz oscillator and 14-bit instruction set yield precise frame timing, while the WDT and BOD guard against brown-out-induced LED glitches during power transitions. With 3.5KB of flash, designers can store multi-pattern sequences in firmware rather than external ROM. The wide-body SOIC-18 footprint dissipates heat adequately at the moderate currents typical of decorative LEDs.
Recommended
Sensor Front-End / Data Acquisition Nodes
The PIC16F628T-04I/SO works as a low-cost sensor front-end, combining two analog comparators for threshold detection with the 16 I/O pins for digital sensor interfaces. Its on-chip EEPROM stores calibration constants next to the sensor, and the CCP+TIMER1 pair measures pulse widths from ultrasonic or IR distance sensors. The 3.0V to 5.5V supply range lets it run from a single Li-ion cell or a 5V USB rail, and the USART outputs sensor readings to a host. Industrial temperature grade suits outdoor weather-station or HVAC duct sensors.
Recommended
Legacy PIC16C62x Replacement / Modernization
The PIC16F628T-04I/SO is the canonical flash-based replacement for one-time-programmable (OTP) PIC16C62x designs, offering identical pinout and peripheral set in the same SOIC-18 footprint. Designers migrating from PIC16C622, PIC16C624, or PIC16C625 can drop the PIC16F628 onto the existing PCB and gain in-circuit reprogrammability, internal oscillator, and EEPROM - eliminating the UV-erase window and external RC network. The 100K flash endurance and 1M EEPROM endurance exceed the typical 1k-cycle OTP programming of the older C-series, making field upgrades trivial.
Recommended
Industrial Control Logic Replacement
In industrial control panels the PIC16F628T-04I/SO replaces discrete logic ICs by integrating timers, comparators, and serial comms in a single 18-pin SOIC. Its industrial temperature grade (-40C to +85C) handles factory-floor conditions, while BOD and POR guard against the unstable supplies typical of motor-drive cabinets. The USART links to a host PLC or HMI, and the CCP module generates timing pulses for sequencing conveyor or pump actuators. Compared to a discrete 74HC logic implementation, the PIC16F628 cuts PCB area and BOM count dramatically.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F628T-04I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F628-04I/SO | PIC16F628A-I/SO | PIC16F627-04I/SO | PIC16F628-20I/SO |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SOIC-18 (0.300 inch wide) | SOIC-18 (same) | SOIC-18 (same) | SOIC-18 (same) | SOIC-18 (same) |
| Program Memory | 3.5KB Flash (2K x 14) | 3.5KB Flash (same) | 3.5KB Flash (same) | 1.75KB Flash (-50%) | 3.5KB Flash (same) |
| Max CPU Frequency | 4 MHz (-04 grade) | 4 MHz (same) | 20 MHz (5x faster, upgrade path) | 4 MHz (same) | 20 MHz (5x faster, same die) |
| RAM | 224 bytes | 224 bytes (same) | 224 bytes (same) | 128 bytes (-43%) | 224 bytes (same) |
| EEPROM | 128 bytes | 128 bytes (same) | 128 bytes (same) | 128 bytes (same) | 128 bytes (same) |
| I/O Pins | 16 | 16 (same) | 16 (same) | 16 (same) | 16 (same) |
| Operating Temperature | -40C to +85C (industrial "I") | -40C to +85C (same) | -40C to +85C (same) | -40C to +85C (same) | -40C to +85C (same) |
| RoHS / Lead-Free | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- True flash-based drop-in for legacy PIC16C62x OTP designs (vs Microchip PIC16C622 / PIC16C624)
- Industrial temperature grade (-40C to +85C) in SOIC-18 wide-body (vs PIC16F628T-04/SO)
- Pin-to-pin compatible with PIC16F628A silicon (vs PIC16F628A-I/SO)
Design Notes
Power the PIC16F628T-04I/SO from a regulated 3.0V to 5.5V supply with a 100 nF decoupling capacitor placed within 5 mm of the VDD pin (pin 10) and a 10 uF bulk capacitor on the same rail. The internal brown-out detect (BOD) is factory-set but can be disabled in configuration bits; for motor-drive or industrial environments keep BOD enabled to avoid corruption during supply dips. The MCU draws approximately 2 mA at 4 MHz over the full industrial temperature range - small enough to power from a coin cell in low-duty-cycle applications.
Place the ICSP pins (RB6/clock, RB7/data, MCLR/VPP) on a 0.1 inch header or test pad so a PICkit 5 can be attached without removing the MCU. Keep the MCLR pull-up resistor (typically 10 kOhm) close to the MCU pin, and never leave MCLR floating. For the SOIC-18 wide-body footprint, follow the land pattern in Microchip's packaging specification document - using the narrow SOIC-16 pattern will cause shorts. Thermal resistance theta-JA for SOIC-18 is approximately 70 C/W, adequate for the 2 mA typical operating current.
Do not confuse the PIC16F628 with the PIC16F84A - the pinouts differ (PIC16F628 has 16 I/O vs 13 useful on PIC16F84A, and pin 9 is MCLR vs pin 4 on PIC16F84A). Verify oscillator selection bits match your hardware: setting HS mode without an external crystal will halt the CPU; setting INTOSC and leaving RA6/RA7 floating will let the internal 4 MHz oscillator run. Configuration bits must be programmed for LVP (low-voltage programming) OFF if you intend to use RB5 as a general I/O, otherwise RB5 stays dedicated to PG programming.
When using the USART at 115200 baud or higher, route the TX/RX traces away from relay or motor driver traces and add a series 100 ohm resistor at the driver output to dampen reflections. The analog comparator inputs (RA0-RA3) are high-impedance; keep traces short and guarded if they are used for sensor thresholds. PORTB weak pull-ups (programmable per pin) are approximately 50 kOhm typical - not strong enough to drive LEDs; use external drivers for any load exceeding 1 mA.
Compliance Information
RoHS/REACH compliant per Microchip product page. SOIC-18 wide-body package is MSL Level 1 per JEDEC J-STD-020. Not AEC-Q100 qualified - choose AEC-Q100 grade PIC variants (PIC16F628A-E/SO automotive grade) for automotive designs.
