PIC16F628T-20I/SS - 8-Bit 20MHz 3.5KB Flash MCU | Microchip
MPN: PIC16F628T-20I/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.18 | $3.18 |
| 10 | $2.86 | $28.60 |
| 100 | $2.45 | $245.00 |
| 500 | $2.1 | $1,050.00 |
| 1,000 | $1.78 | $1,780.00 |
PIC16F628T-20I/SS Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, non-volatile program memory (flash or ROM), volatile data memory (RAM), EEPROM for persistent user data, and configurable digital peripherals. PIC16F-series MCUs use Microchip's enhanced mid-range RISC core with only 35 single-word instructions, so almost every instruction executes in one instruction cycle. The PIC16F628T-20I/SS sits within the hypernym hierarchy: 8-bit microcontroller -> PIC16 mid-range MCU -> PIC16F62x family -> flash-based PIC MCU -> Microchip PIC microcontroller portfolio.
Key features of the PIC16F628T-20I/SS include: an integrated 4 MHz internal oscillator (no external crystal required for many designs); two analog comparators with a programmable on-chip voltage reference; a USART module for asynchronous/synchronous serial communication; a 16-bit capture/compare/PWM module and an 8-bit timer/counter; flash program memory with 100K endurance cycles; and brown-out reset (BOR), power-on reset (POR), power-up timer (PWRT), oscillator start-up timer (OST), and watchdog timer (WDT) with a dedicated on-chip RC oscillator.
The architecture uses a Harvard bus (separate program and data memory paths), allowing instruction fetch and operand read to occur in the same cycle. CMOS process technology gives the part its low-power characteristics, including very low power-down current typical of PIC mid-range parts and several oscillator operating modes (internal RC, external RC, crystal, and LP modes) selected by configuration fuses.
Typical applications include low-cost embedded control nodes (appliance controllers, sensor hubs, simple motor/solenoid drivers), automotive body-electronics subsystems (interior lighting, fan control, sensor interfaces), hobby and education boards, replacement of legacy PIC16F84/PIC16F627 designs requiring more RAM and EEPROM, and battery-powered instrumentation where the internal oscillator and brown-out reset are advantageous.
When designing with this part, use the 20-pin SSOP land pattern and respect the I/O current-source/-sink limits when driving LEDs directly. MPLAB X IDE and MPLAB XC8 (or legacy Hi-Tech PICC) are the recommended toolchains, and the PICkit 5 in-circuit debugger supports the PIC16F62x family for production-ready programming.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives, comparison parameters, and practical design notes that are not found on the manufacturer datasheet alone.
Drop-in alternatives for PIC16F628T-20I/SS — 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-20I/SS (same form factor and footprint) — differing in Package, Core Architecture, Internal Oscillator, Program Memory (Flash), RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F628-20I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F628T-20E/SS
✅ Drop-In✓ In Stock
$2.5 / Unit
View Datasheet →PIC16F628A-I/SS
✅ Drop-In✓ In Stock
$1.41 / Unit
View Datasheet →PIC16F627A-I/SS
✅ Drop-In✓ In Stock
$1.12 / Unit
View Datasheet →PIC16F88-I/SS
✅ Drop-In✓ In Stock
$3.08 / Unit
View Datasheet →PIC16F628T-20I/SS Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology |
| Series | PIC16F |
| Core | PIC16 mid-range 8-bit RISC |
| Instruction Set Width | 14-bit |
| Number of Instructions | 35 single-word |
| Program Memory Type | Flash |
| Program Memory Size | 3.5 KB (2K x 14) |
| RAM Size | 224 bytes |
| EEPROM Size | 128 bytes |
| Maximum Clock Speed | 20 MHz |
| Instruction Cycle | 200 ns |
| Supply Voltage Range | 3.0 V to 5.5 V |
| Number of I/O Pins | 16 |
| Operating Temperature | -40 °C to +85 °C (Industrial) |
| Package | 20-pin SSOP (5.30 mm) |
| Mounting Type | Surface Mount |
| Internal Oscillator | 4 MHz (typical) |
| On-chip Peripherals | Brown-out Reset, Power-on Reset, Watchdog Timer, 2x Analog Comparators, USART, 1x 16-bit CCP, 1x 8-bit Timer |
| RoHS Status | Compliant (Pb-free, Matte-Tin finish) |
PIC16F628T-20I/SS Pin Configuration
| Pin 1 | RA2/AN2/VREF — GPIO RA2 / analog comparator input / voltage reference |
| Pin 2 | RA3/AN3/CMP1 — GPIO RA3 / analog comparator input / comparator 1 output |
| Pin 3 | RA4/AN4/T0CKI — GPIO RA4 / comparator input / Timer0 clock input |
| Pin 4 | RA5/MCLR/VPP — GPIO RA5 / Master Clear (reset) / programming voltage |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — GPIO RB0 / external interrupt |
| Pin 7 | RB1/RX/DT — GPIO RB1 / USART RX / I2C data |
| Pin 8 | RB2/TX/CK — GPIO RB2 / USART TX / I2C clock |
| Pin 9 | RB3/CCP1 — GPIO RB3 / Capture-Compare-PWM output |
| Pin 10 | RB4/PGM — GPIO RB4 / low-voltage programming |
| Pin 11 | RB5 — GPIO RB5 |
| Pin 12 | RB6/T1OSO/T1CKI — GPIO RB6 / Timer1 oscillator output / Timer1 clock input |
| Pin 13 | RB7/T1OSI — GPIO RB7 / Timer1 oscillator input |
| Pin 14 | VDD — Positive supply voltage (3.0 V to 5.5 V) |
| Pin 15 | OSC2/CLKOUT — Crystal/ceramic resonator output / clock output |
| Pin 16 | OSC1/CLKIN — Crystal/ceramic resonator input / external clock input |
| Pin 17 | RA0/AN0 — GPIO RA0 / analog comparator input |
| Pin 18 | RA1/AN1 — GPIO RA1 / analog comparator input |
| Pin 19 | RA6/OSC2 — GPIO RA6 / alternate oscillator output |
| Pin 20 | RA7/OSC1 — GPIO RA7 / alternate oscillator input |
Typical Applications
PIC16F628T-20I/SS is suitable for 6 applications: Appliance Control Boards, Automotive Body Electronics, Battery-Powered Sensor Hubs, Industrial Sensor Interface Boards, Hobby Electronics and Education, Replacement of Legacy PIC16F84 Designs.
Appliance Control Boards
The PIC16F628T-20I/SS is well-suited for low-cost appliance controller boards because it integrates a USART for HMI/keypad communication, two analog comparators for sensor-threshold detection (temperature, water level), and 16 GPIO lines sufficient for relay drivers, indicator LEDs, and a switch matrix. Its 3.0-5.5 V supply range and internal 4 MHz oscillator eliminate the external crystal and voltage regulator complexity, shrinking BOM cost in washing machines, microwave ovens, and dishwashers.
Recommended
Automotive Body Electronics
The PIC16F628T-20I/SS handles small automotive body-electronics nodes such as interior lighting controllers, mirror adjusters, and HVAC mode switches because its 16 GPIO lines can directly sink LED currents, and its industrial -40C to +85C temperature grade covers cabin-environment deployments. Brown-out reset and watchdog timer maintain reliable operation across cranking transients, while the flash-based program memory supports OTA-style firmware updates via the USART boot loader path.
Recommended
Battery-Powered Sensor Hubs
For battery-powered sensor hubs, the PIC16F628T-20I/SS operates down to 3.0 V from two AA cells and provides low-power sleep modes typical of PIC mid-range MCUs, enabling multi-year battery life when the CPU wakes only briefly to read a sensor and transmit over USART. The internal 4 MHz oscillator removes the always-on current of an external crystal, and the on-chip analog comparators can directly threshold battery voltage without waking the ADC path.
Recommended
Industrial Sensor Interface Boards
Industrial sensor-interface boards use the PIC16F628T-20I/SS to read digital sensors (Hall-effect, optical encoders, proximity switches), apply calibration in firmware, and stream processed data over RS-232/RS-485 via the on-chip USART. The watchdog timer detects firmware hangs in unattended installations, while the 128-byte EEPROM stores calibration constants and serial numbers for traceability. The SSOP-20 footprint also suits compact DIN-rail-mounted modules.
Recommended
Hobby Electronics and Education
The PIC16F628T-20I/SS remains a popular PIC for hobbyist boards and university embedded-systems courses because its 35 single-word instruction set is easy to teach, MPLAB X IDE with XC8 compiler is free, and the PICkit 5 programmer/debugger is widely available. The internal oscillator simplifies first-time bring-up, while the USART allows students to print debug output to a terminal - a key teaching workflow.
Recommended
Replacement of Legacy PIC16F84 Designs
Many legacy designs that use the older PIC16F84 or PIC16F84A can be upgraded to the PIC16F628T-20I/SS in the same 20-pin SSOP footprint, gaining 4x more flash (3.5 KB vs 1 KB), more RAM (224 B vs 68 B), and on-chip EEPROM (128 B) that the F84 lacks. The PIC16F628T-20I/SS also adds a USART and analog comparators, enabling feature expansion without changing the PCB. Code migration requires recompiling with XC8 for the PIC16F628 header file.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F628T-20I/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F628-20I/SS | PIC16F628T-20E/SS | PIC16F628A-I/SS | PIC16F627A-I/SS | PIC16F88-I/SS |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 20-pin SSOP | 20-pin SSOP - same | 20-pin SSOP - same | 20-pin SSOP - same | 20-pin SSOP - same | 20-pin SSOP - same |
| Program Flash | 3.5 KB | 3.5 KB | 3.5 KB | 3.5 KB | 1.75 KB | 3.5 KB (7 KB addressable) |
| RAM | 224 bytes | 224 bytes | 224 bytes | 224 bytes | 128 bytes | 368 bytes |
| EEPROM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 256 bytes |
| Max Clock Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 2.0 V to 5.5 V |
| Operating Temperature | -40 °C to +85 °C (Industrial) | -40 °C to +85 °C | -40 °C to +125 °C (Extended) | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C |
| ADC | None (comparators only) | None | None | None | None | 10-bit ADC, 7 channels |
Key Differentiators
- Tape-and-reel packaging for high-volume SMT assembly (vs PIC16F628-20I/SS)
- Extended temperature variant available in same SSOP-20 footprint (vs PIC16F628T-20I/SS vs PIC16F628T-20E/SS)
- A-revision silicon provides modernized interrupt controller (vs PIC16F628A-I/SS)
Design Notes
Place a 0.1 µF decoupling capacitor as close as possible to the VDD pin (pin 14) and a bulk capacitor (e.g., 10 µF tantalum or ceramic) at the board power entry. For battery-powered designs, the PIC16F628T-20I/SS supports operation down to 3.0 V, but verify that the BOR threshold is configured to match the minimum battery voltage to avoid spurious resets during brown-out. The internal 4 MHz oscillator eliminates the need for an external crystal in most applications, reducing both BOM cost and quiescent current.
Route the MCLR pin (pin 4) carefully - it is shared with the VPP programming voltage input, and a long trace or large capacitance can impede in-circuit programming with the PICkit 5. Keep the MCLR trace short and add the typical 10 kΩ pull-up to VDD. If using the internal oscillator, leave OSC1/OSC2 (pins 15-16) as no-connects or tie OSC1 to ground through 10 kΩ to avoid noise pickup. Add a ground pour under the SSOP-20 footprint for thermal dissipation.
Estimated: at 20 MHz with VDD = 5 V, the PIC16F628T-20I/SS typically draws 10-15 mA active current. At 3.3 V and 4 MHz internal oscillator, expect 1-2 mA active current. Sleep current is typically < 1 µA but varies by temperature and configuration-fuse settings. A common design pitfall is forgetting to configure the watchdog timer postscaler; the WDT defaults to the longest timeout (~2.3 s) and may unexpectedly reset the MCU in time-critical loops. Always clear the WDTCON register properly or disable WDT in configuration bits if not needed.
When using the USART (RB1/RX, RB2/TX) at high baud rates (≥ 115200), keep the traces short and avoid routing them parallel to noisy switching lines. Add a series resistor (10-100 Ω) on TX if the receiver is more than a few centimeters away, to damp ringing. The analog comparators are sensitive to supply noise; if using them for sensor thresholding, add a small RC filter (1 kΩ + 100 nF) on the input pin to reject high-frequency interference that could cause false comparator trips.
Compliance Information
RoHS-compliant Pb-free (matte-tin) finish per Microchip product page. Industrial temperature grade -40C to +85C (I-suffix); E-suffix variant PIC16F628T-20E/SS provides extended -40C to +125C. AEC-Q100 qualification status is not explicitly stated for the standard I-suffix part.
