PIC16LC622AT-04/SO - 8-bit OTP MCU, 3.5KB, 4MHz | Microchip
MPN: PIC16LC622AT-04/SO ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.1985 | $1.20 |
| 10 | $1.14 | $11.40 |
| 100 | $1.05 | $105.00 |
| 500 | $0.95 | $475.00 |
| 1,000 | $0.85 | $850.00 |
PIC16LC622AT-04/SO Overview
A microcontroller (MCU) is a single-chip computer integrating a CPU core, program memory, working RAM, and peripheral I/O onto one die. The PIC16C family uses Microchip's enhanced Harvard RISC architecture, where program and data buses are physically separated, allowing instruction fetch to occur in parallel with operand reads and giving deterministic interrupt response. PIC microcontrollers belong to the broader class of 8-bit embedded microcontrollers within the semiconductor hierarchy of integrated circuits, and they are widely adopted in commercial and industrial control applications for their simple toolchain and low system cost.
Key features include thirteen digital I/O pins, two 8-bit timers with optional 16-bit mode, a Watchdog Timer with on-chip RC oscillator, power-on reset, power-saving SLEEP mode, and an internal/external oscillator select. The 'LC' suffix denotes the low-voltage CMOS process, while the 'A' indicates the silicon revision and the 'T' indicates tape-and-reel packaging. The '04' speed grade corresponds to the 4MHz oscillator limit. The OTP program memory allows one-time programming during production.
Architecture depth: the PIC16C62x devices implement a 14-bit instruction word with an 8-level hardware stack, supporting direct, indirect, and relative addressing modes. Brown-out Reset and Power-on Reset are integrated. The I/O ports are bidirectional with weak pull-up options on PORTB. An 8-bit prescaler is shared between Timer0 and the Watchdog Timer.
Typical applications include appliance control, sensor signal conditioning front-ends, low-cost consumer products, industrial logic replacement, and battery-powered instrumentation. The SOIC-18 package supports hand-soldered prototypes and high-density SMT production lines alike.
Designers should verify that the 2.5V-6.0V supply range matches the system rail, and confirm that the 13 I/O pins are sufficient before committing. OTP memory is one-time programmable, so firmware must be 100% validated before the production run.
This page synthesizes distributor pricing from Mouser, DigiKey, and LCSC, plus drop-in alternative MPNs from the Microchip PIC16C family and practical design notes not consolidated on any single distributor page.
Drop-in alternatives for PIC16LC622AT-04/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 PIC16LC622AT-04/SO (same form factor and footprint) — differing in Operating Temperature Range, Program Memory Size, Program Memory Type, RAM Size, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LC622A-04E/SO
✅ Drop-In✓ In Stock
$2.13 / Unit
View Datasheet →PIC16LC622A-04/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC622A-04I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC621AT-04I/SO
✅ Drop-In✓ In Stock
$1.55 / Unit
View Datasheet →PIC16LC620A-04/SO
✅ Drop-In✓ In Stock
$2.15 / Unit
View Datasheet →PIC16LC622AT-04/SO Maximum Ratings & Electrical Characteristics
| Core Processor | PIC |
| Core Size | 8-bit |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 3.5KB (2K x 14) |
| RAM Size | 128 bytes |
| Number of I/O Pins | 13 |
| Maximum Clock Frequency | 4 MHz |
| Supply Voltage Range | 2.5 V to 6.0 V |
| Package | 18-SOIC (0.295 inch / 7.50 mm width) |
| Operating Temperature Range | -40C to +85C (commercial, per 'C' suffix absent implies standard temp) |
| Mounting Type | Surface Mount |
| Series | PIC 16C |
| Sub-series | PIC16LC622A (low-voltage CMOS) |
| Oscillator Type | External |
| Timers | 2 x 8-bit (TMR0, TMR1) + Watchdog Timer |
| RoHS Status | Compliant |
| Packaging | Tape & Reel (T suffix) |
PIC16LC622AT-04/SO Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (Reset) input / Programming voltage |
| Pin 2 | RA0 — Digital I/O, PORTA bit 0 |
| Pin 3 | RA1 — Digital I/O, PORTA bit 1 |
| Pin 4 | RA2 — Digital I/O, PORTA bit 2 |
| Pin 5 | RA3 — Digital I/O, PORTA bit 3 |
| Pin 6 | RA4/T0CKI — Digital I/O, PORTA bit 4 / Timer0 clock input |
| Pin 7 | VSS — Ground reference |
| Pin 8 | VDD — Positive supply voltage (2.5V-6.0V) |
| Pin 9 | OSC1/CLKIN — Oscillator input / External clock input |
| Pin 10 | OSC2/CLKOUT — Oscillator output / Clock output |
| Pin 11 | RC0 — Digital I/O, PORTC bit 0 |
| Pin 12 | RC1 — Digital I/O, PORTC bit 1 |
| Pin 13 | RC2 — Digital I/O, PORTC bit 2 |
| Pin 14 | RC3 — Digital I/O, PORTC bit 3 |
| Pin 15 | RC4 — Digital I/O, PORTC bit 4 |
| Pin 16 | RC5 — Digital I/O, PORTC bit 5 |
| Pin 17 | RC6 — Digital I/O, PORTC bit 6 |
| Pin 18 | RC7 — Digital I/O, PORTC bit 7 |
Typical Applications
PIC16LC622AT-04/SO is suitable for 6 applications: Home Appliance Controllers, Battery-Powered Sensor Frontends, Industrial Logic Replacement, Consumer Remote Control Units, Automotive Body Electronics (legacy), Educational and Hobby Projects.
Home Appliance Controllers
The PIC16LC622AT-04/SO fits home appliance controllers (washing machines, microwave ovens, dishwashers) thanks to its 3.5KB OTP program memory for fixed-function firmware, 13 digital I/O pins for driving relays, keypads, and seven-segment displays, and 2.5V-6.0V supply range matching 5V logic rails. The 4MHz clock and Watchdog Timer provide deterministic control loop execution. Compared with 32-bit ARM Cortex alternatives, this PIC16C costs less than half and requires no external oscillator for many timing loops, reducing BOM and PCB area in cost-sensitive white-goods.
Recommended
Battery-Powered Sensor Frontends
The PIC16LC622AT-04/SO suits battery-powered sensor frontends because the LC CMOS process keeps quiescent current low, and the SLEEP mode combined with the Watchdog Timer enables wake-on-event duty cycling. The 13 I/O pins can host analog sensor inputs via external signal conditioning, while the 4MHz clock delivers sufficient throughput for sampled data at low update rates. Unlike higher-pin-count MCUs, the SOIC-18 footprint keeps PCB area to 80 mm^2, allowing compact sensor pods running from 2 AA cells.
Recommended
Industrial Logic Replacement
The PIC16LC622AT-04/SO replaces legacy CMOS/TTL glue logic in industrial control cabinets by consolidating timing, sequencing, and I/O expansion into one chip. The 3.5KB OTP memory holds ladder-logic replacements, and the 13 I/O pins can drive optocouplers or interface with 24V industrial bus signals via external buffers. The -40C to +85C operating range supports factory-floor enclosures. Replacing a discrete-logic board with one PIC16C reduces assembly cost by 30-50% and adds firmware-driven flexibility.
Recommended
Consumer Remote Control Units
The PIC16LC622AT-04/SO fits consumer remote controls (TV, audio, smart-home IR/RF handsets) thanks to its small SOIC-18 package, 13 I/O for keypad matrix scanning and IR LED drive, and ultra-low SLEEP current for coin-cell operation. The 3.5KB OTP memory stores transmission protocols and timing tables, while the 4MHz instruction cycle enables sub-millisecond response latency. Compared with a discrete IR encoder IC, this MCU supports multi-protocol firmware uploads in production without mask changes.
Recommended
Automotive Body Electronics (legacy)
The PIC16LC622AT-04/SO historically served automotive body controllers (mirror adjusters, window lifters, lighting sequencers) where cost dominates over AEC-Q100 compliance for low-criticality modules. The 13 I/O pins drive H-bridges and LED arrays, and the 4MHz clock handles sequencing tasks. Note: this part is NOT AEC-Q100 qualified, so automotive designs today should migrate to PIC16F628A-I/SO or PIC16F88-I/SO with full automotive-grade qualification.
Recommended
Educational and Hobby Projects
The PIC16LC622AT-04/SO is widely used in educational microcontroller courses and hobby projects (LED cubes, line-following robots, simple data loggers) because of its mature toolchain (MPLAB, MPASM) and forgiving 2.5V-6.0V supply range. The 3.5KB OTP memory accommodates typical teaching programs, and the SOIC-18 package fits standard breakout boards. The Watchdog Timer teaches robust embedded design, while the low cost keeps classroom lab kits affordable for student teams.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC622AT-04/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LC622A-04E/SO | PIC16LC622A-04/SO | PIC16LC622A-04I/SO | PIC16LC621AT-04I/SO | PIC16LC620A-04/SO |
|---|---|---|---|---|---|---|
| Package | 18-SOIC | 18-SOIC | 18-SOIC | 18-SOIC | 18-SOIC | 18-SOIC |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 3.5KB OTP | 3.5KB OTP | 3.5KB OTP | 3.5KB OTP | 1.75KB OTP | 0.875KB OTP |
| RAM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 80 bytes | 68 bytes |
| Maximum Clock | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| I/O Pins | 13 | 13 | 13 | 13 | 13 | 13 |
| Supply Voltage | 2.5V to 6.0V | 2.5V to 6.0V | 2.5V to 6.0V | 2.5V to 6.0V | 2.5V to 6.0V | 2.5V to 6.0V |
| Memory Type | OTP | OTP | OTP | OTP | OTP | OTP |
| Lifecycle | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete |
Key Differentiators
- Identical silicon to PIC16LC622A-04/SO with tape-and-reel convenience (vs PIC16LC622A-04/SO)
- Higher program memory within the same SOIC-18 footprint (vs PIC16LC620A-04/SO)
- Industrial temperature grade option available within family (vs PIC16LC621AT-04I/SO)
Design Notes
The PIC16LC622AT-04/SO operates from 2.5V to 6.0V. Place a 100nF decoupling capacitor as close as possible to the VDD (pin 8) and VSS (pin 7) pair to suppress supply noise. For battery applications, add a 10uF bulk capacitor near VDD to handle peak current transients when the I/O pins switch. The Watchdog Timer continues to run in SLEEP mode when configured by the WDTE fuse, which keeps SLEEP current non-zero - disable WDTE for true low-power standby.
OTP (One-Time Programmable) memory cannot be erased or rewritten. Validate the firmware exhaustively on a Flash-equivalent PIC16F628A-I/SO before committing to OTP production. Also note that MCLR must be tied to VDD through a 10k resistor for normal operation; leaving MCLR floating will cause erratic resets. The 'T' suffix on this part denotes tape-and-reel packaging - if you need tube packaging for prototype work, order PIC16LC622A-04/SO (no T).
The 18-SOIC package has a 0.300-inch row spacing and 1.27 mm pin pitch. Use a ground plane on the bottom layer to reduce EMI on the OSC1/OSC2 traces. Keep the oscillator crystal or resonator within 5 mm of pins 9 and 10, with short, symmetrical traces to minimize parasitic capacitance. For noisy industrial environments, add a 4.7k pull-up on MCLR and a 100pF capacitor to ground to filter ESD transients.
Compliance Information
RoHS compliant per distributor listings. The PIC16LC622A is not AEC-Q100 qualified; for automotive designs migrate to PIC16F628A-I/SO or PIC16F88-I/SO with full automotive qualification.