PIC16C622AT-20I/SO - 8-bit OTP MCU, 3.5KB, 20MHz SOIC-18
MPN: PIC16C622AT-20I/SO ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.62 | $26.20 |
| 100 | $2.3 | $230.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.82 | $1,820.00 |
PIC16C622AT-20I/SO Overview
An OTP microcontroller is a type of embedded MCU whose program memory is programmed once and is non-erasable, positioned between ROM-based mask parts (cheaper at high volume) and flash-based parts (re-programmable). In the broader taxonomy, OTP MCUs sit inside the hierarchy: microcontroller -> embedded MCU -> 8-bit MCU -> CMOS RISC MCU -> semiconductor IC. The PIC16C62X family targets cost-sensitive industrial control, appliance, and consumer applications where code stability and low unit cost outweigh the need for field re-programmability.
Key features include Harvard RISC instruction set with 35 single-word instructions, 200 ns instruction cycle at 20 MHz, two 8-bit timer/counters (Timer0, Timer2), one analog comparator with programmable reference, 13 digital I/O pins with individual direction control, power-on reset (POR), brown-out reset (BOR), and watchdog timer (WDT) with on-chip RC oscillator. The device supports in-circuit serial programming (ICSP) via RB6/RB7 pins despite being OTP, enabling factory pre-programming.
Architecturally, the PIC16C622A uses a 14-bit instruction word with a separate data path (Harvard architecture), enabling simultaneous instruction fetch and data access. The 8-level deep hardware stack and 4 interrupt sources provide deterministic real-time response. The on-chip RC oscillator option and internal watchdog with dedicated 38 kHz RC oscillator allow reduced BOM cost in standalone designs.
Typical applications include industrial control logic, appliance controllers, security alarm panels, smart sensor interfaces, automotive body electronics (non-safety), and low-end consumer products. The wide 3-5.5V operating range and industrial -40C to +85C temperature grade suit outdoor or factory-floor deployments.
When designing with this part, note that OTP memory cannot be re-programmed in-circuit. Use a flash equivalent (e.g., PIC16F628A) for prototypes. The 18-pin SOIC (300 mil body) package is footprint-compatible with several PIC16F62X family parts, simplifying migration between flash and OTP variants.
Drop-in alternatives for PIC16C622AT-20I/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 PIC16C622AT-20I/SO (same form factor and footprint) — differing in Program Memory Size, Package, Program Memory Type, Mounting Type, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C622A-20I/SO
✅ Drop-In✓ In Stock
$2.89 / Unit
View Datasheet →PIC16C622A-04I/SO
✅ Drop-In✓ In Stock
$2.72 / Unit
View Datasheet →PIC16C622A-04I/P
✅ Drop-In✓ In Stock
$1.95 / Unit
View Datasheet →PIC16C622A-20E/P
✅ Drop-In✓ In Stock
$1.28 / Unit
View Datasheet →PIC16C621AT-20I/SO
✅ Drop-In✓ In Stock
$2.3 / Unit
View Datasheet →PIC16F628A-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C622AT-20I/SO Maximum Ratings & Electrical Characteristics
| Family | PIC16C62X |
| Core | 8-bit RISC (Harvard) |
| Program Memory Type | OTP (One-Time-Programmable) |
| Program Memory Size | 3.5 KB (2048 x 14-bit words) |
| RAM | 128 bytes |
| EEPROM | None |
| Max CPU Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns at 20 MHz |
| I/O Pins | 13 |
| Timers | 2 x 8-bit (Timer0, Timer2) |
| Comparators | 1 x analog comparator |
| ADC | None |
| Supply Voltage (VDD) | 3.0 V to 5.5 V |
| Operating Temperature | -40C to +85C (Industrial) |
| Package | 18-SOIC (0.295", 7.50 mm width) |
| Mounting Type | Surface Mount |
| Programming | ICSP (in-circuit serial programming) - factory only |
| Watchdog Timer | Yes, with on-chip RC oscillator |
| Brown-out Reset | Yes |
PIC16C622AT-20I/SO Pin Configuration
| Pin 1 | RA2/AN2/VREF — Bidirectional I/O / analog channel 2 / comparator reference |
| Pin 2 | RA3/AN3/CMP1 — Bidirectional I/O / analog channel 3 / comparator-1 output |
| Pin 3 | RA4/T0CKI — Bidirectional I/O / Timer0 clock input |
| Pin 4 | RA5 — Bidirectional I/O |
| Pin 5 | VSS — Ground |
| Pin 6 | RB0/INT — Bidirectional I/O / external interrupt |
| Pin 7 | RB1 — Bidirectional I/O |
| Pin 8 | RB2 — Bidirectional I/O |
| Pin 9 | RB3 — Bidirectional I/O |
| Pin 10 | RB4 — Bidirectional I/O (interrupt-on-change) |
| Pin 11 | RB5 — Bidirectional I/O (interrupt-on-change) |
| Pin 12 | RB6/PGC — Bidirectional I/O / ICSP clock |
| Pin 13 | RB7/PGD — Bidirectional I/O / ICSP data |
| Pin 14 | VDD — Positive supply (3.0V to 5.5V) |
| Pin 15 | OSC2/CLKOUT — Oscillator output / clock out (XT/HS/LP/RC modes) |
| Pin 16 | OSC1/CLKIN — Oscillator input / external clock in (XT/HS/LP/RC modes) |
| Pin 17 | RA0/AN0 — Bidirectional I/O / analog channel 0 |
| Pin 18 | RA1/AN1 — Bidirectional I/O / analog channel 1 |
Typical Applications
PIC16C622AT-20I/SO is suitable for 6 applications: Industrial Control Logic, Appliance Control Boards, Security Alarm Panels, Smart Sensor Interface Modules, Automotive Body Electronics (Non-Safety), Low-End Consumer Products.
Industrial Control Logic
The PIC16C622AT-20I/SO fits industrial control logic blocks such as relay drivers, solenoid multiplexers, and discrete I/O expansion because it offers 13 digital I/O, two 8-bit timers for PWM or event counting, and an industrial -40C to +85C operating range. Its 200 ns instruction cycle at 20 MHz executes the 14-bit instruction set deterministically, allowing tight control loops in motor starters and process interlocks. Placed on a 3.3V or 5V rail, it survives factory floor noise and ESD events; combined with brown-out reset and watchdog timer, it auto-recovery from brown-out events without operator intervention - unlike a discrete logic controller which would hang.
Recommended
Appliance Control Boards
For appliance boards (washing machines, dishwashers, microwave ovens) the PIC16C622AT-20I/SO provides the deterministic 8-bit RISC control needed for motor sequencing, sensor monitoring, and front-panel key scans. The OTP memory prevents reverse engineering of firmware, a security advantage over flash MCUs, while the analog comparator reads thermistor or level-sensor signals without an ADC. Operating at 3-5.5V, it pairs directly with white-goods power supplies. Compared to a 32-bit MCU, this part costs less than $1 at volume while still providing 20 MHz processing - ideal for high-volume cost-down products where firmware is locked.
Recommended
Security Alarm Panels
In security alarm panels and intrusion-detection control units, the PIC16C622AT-20I/SO fits because of its OTP code security, 13 I/O for zone monitoring and siren/keypad control, and on-chip analog comparator for tamper detection via bridge sensors. The watchdog timer with dedicated 38 kHz RC oscillator prevents code lock-up, while brown-out reset handles power-line transients common in alarm installations. The 18-SOIC package is footprint-compatible with the flash-based PIC16F628A, easing migration for panels that later need field update capability. Its 200 ns instruction cycle is fast enough to scan 8 zones at sub-millisecond rate.
Recommended
Smart Sensor Interface Modules
The PIC16C622AT-20I/SO serves well as a smart sensor interface for environmental or process sensors, translating analog comparator outputs into digital protocols over its GPIO. With 128 bytes RAM and 3.5 KB program memory, it can host calibration tables and digital filtering without needing an external EEPROM. The 20 MHz core executes smoothing algorithms in real time, while the watchdog timer guards against software faults in unattended deployments. Compared to bare comparators, it adds local intelligence (linearization, hysteresis) at a BOM cost of under $1.50 - and unlike a flash MCU, OTP code resists IP theft.
Recommended
Automotive Body Electronics (Non-Safety)
For non-safety automotive body modules like interior lighting controllers, seat-position memory, and accessory timers, the PIC16C622AT-20I/SO provides 3.0V-5.5V operation over the full automotive 12V-rail derived range when properly regulated, 13 I/O for switch and LED matrix control, and deterministic 8-bit RISC timing. The industrial -40C to +85C grade handles cabin and under-hood-near temperatures, though for under-hood deployment use the extended -40C to +125C grade PIC16C622A-20E/P. Compared to a discrete logic array, it cuts PCB area by 70% while adding programmable behaviour.
Recommended
Low-End Consumer Products
The PIC16C622AT-20I/SO fits low-end consumer products such as toy controllers, remote control handsets, and small kitchen appliances because it combines 13 I/O for key/LED handling, two timers for blinking/beeping, and an analog comparator for battery-voltage or touch sensing. The OTP memory locks the firmware to prevent cloning of toy game logic, and the 18-SOIC package is reflow-compatible with high-volume SMT lines. At $1.80-$2.00 per unit in 1000-piece quantities, it keeps BOM cost low while delivering 20 MHz RISC performance that executes the typical toy logic in tens of microseconds per loop.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C622AT-20I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C622A-20I/SO | PIC16C622A-04I/SO | PIC16F628A-I/SO |
|---|---|---|---|---|
| Package | 18-SOIC (0.295") | 18-SOIC (0.295") - same | 18-SOIC (0.295") - same | 18-SOIC (0.295") - same |
| Brand | Microchip Technology | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same |
| Program Memory | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB Flash |
| Max Frequency | 20 MHz | 20 MHz | 4 MHz (-80%) | 20 MHz |
| RAM | 128 bytes | 128 bytes | 128 bytes | 224 bytes |
| I/O Pins | 13 | 13 | 13 | 16 |
| Temperature Grade | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) |
| Memory Type | OTP | OTP | OTP | Flash (field-programmable) |
| Lifecycle Status | NRND | NRND | NRND | Active |
Key Differentiators
- OTP memory provides firmware IP protection (vs PIC16F628A-I/SO)
- Industrial -40C to +85C temperature grade (vs PIC16C622AT-20/SO)
- 20 MHz RISC core for deterministic timing (vs PIC16C622A-04I/SO)
Design Notes
PIC16C622AT-20I/SO uses OTP (one-time-programmable) flash - code cannot be erased or rewritten after programming. Always validate firmware on a flash-equivalent (PIC16F628A-I/SO) development board first, then commit final code to OTP parts for production. Sending bad firmware to OTP parts bricks the device permanently.
Place a 100 nF decoupling capacitor within 5 mm of the VDD pin (pin 14) and a 10 uF bulk capacitor near the ICSP connector. For battery-powered sensor designs, switch to the low-frequency PIC16C622A-04I/SO (4 MHz) variant - its lower clock reduces active current by approximately 4x. Use MCP1700 LDOs for low-quiescent supply rail.
The 18-SOIC package (0.295 inch body width) has a JEDEC MS-013 footprint. Keep-out area around MCLR/VPP pin (pin 12) for high-voltage ICSP programming probe clearance. Do not route switching signals or analog inputs under the ICSP clock/data pins (RB6/RB7) to prevent programming noise coupling.
Compliance Information
Compliance status not confirmed in provided Verified Web Data; industrial -40C to +85C temperature grade is standard (not AEC-Q100). For automotive deployments, Microchip recommends verifying compliance with the manufacturer.