PIC16C622-20/SS - 8-Bit CMOS EPROM MCU, 3.5KB, 13 I/O | Microchip
MPN: PIC16C622-20/SS ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.1183 | $2.12 |
| 10 | $1.95 | $19.50 |
| 100 | $1.72 | $172.00 |
| 500 | $1.55 | $775.00 |
| 1,000 | $1.38 | $1,380.00 |
PIC16C622-20/SS Overview
A microcontroller is a single-chip computer that integrates a CPU core, program memory, working RAM, and peripheral interfaces into one device. The PIC16C62X belongs to the PIC16 mid-range family, a RISC architecture family within Microchip's 8-bit MCU hierarchy that sits between baseline PIC10/12/14 devices and the enhanced PIC18 family. EPROM (Erasable Programmable Read-Only Memory) is one-time-erasable UV-window program memory, distinguishing this part from flash-based PIC16F equivalents and making it suitable for legacy and development environments where windowed erasure is acceptable.
Key features include 35 single-word instructions, 14-bit instruction word, 8-level deep hardware stack, direct/indirect/relative addressing, power-on reset, power-up timer, oscillator start-up timer, and brown-out detection. The device operates from 3.0 V to 6.0 V across commercial 0 °C to +70 °C and industrial -40 °C to +85 °C grades. The PIC16C622 variant adds a single analog comparator and a voltage reference module, distinguishing it from the PIC16C620 (no comparator) and PIC16C621 (comparator only).
Typical applications include legacy embedded control systems, industrial sensor interfaces, simple motor control loops, appliance controllers, security and alarm panels, and automotive body electronics where pin-compatible PIC16F replacements are not required. The wide 3.0 V-6.0 V supply range supports both 3.3 V and 5 V rails commonly found in legacy industrial designs.
When designing with this device, note that EPROM parts require a quartz-windowed package for erasure and a PROM programmer for code loading. Modern designs typically migrate to the pin-compatible flash-based PIC16F628 or PIC16F88, which share the SSOP-20 footprint but support in-circuit reprogramming. The PIC16C622-20/SS is recommended for legacy maintenance, existing design replication, and applications where the EPROM technology is mandated.
Drop-in alternatives for PIC16C622-20/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 PIC16C622-20/SS (same form factor and footprint) — differing in Package, Program Memory Size, Program Memory Type, Instruction Set, Operating Temperature Range.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F628A-20/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C622-20I/SS
✅ Drop-In✓ In Stock
$1.44 / Unit
View Datasheet →PIC16C622-20E/SS
✅ Drop-In✓ In Stock
$2.49 / Unit
View Datasheet →PIC16C621A-20/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C620A-20/SS
✅ Drop-In✓ In Stock
$1.72 / Unit
View Datasheet →PIC16F88-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C622-20/SS Maximum Ratings & Electrical Characteristics
| Program Memory Type | EPROM (UV-erasable, one-time programmable in package) |
| Program Memory Size | 3.5 KB (2048 x 14-bit words) |
| Data RAM | 128 bytes |
| Data EEPROM | 128 bytes |
| CPU Core | PIC16 RISC, 8-bit, 14-bit instruction word |
| Maximum Clock Frequency | 20 MHz |
| Instruction Set Size | 35 single-word instructions |
| I/O Pins | 13 |
| Timers | 1 x 8-bit Timer/Counter with prescaler |
| Watchdog Timer | Yes (independent RC oscillator) |
| Analog Comparator | 1 (with internal voltage reference) |
| Supply Voltage Range | 3.0 V to 6.0 V |
| Operating Temperature Range | 0 C to +70 C (commercial, -20 suffix) |
| Package Type | SSOP-20 (Shrink Small Outline, 5.30 mm body, 0.65 mm pitch) |
| Mounting Type | Surface Mount |
| Packaging | Tube |
| Power-on Reset / Brown-out Reset | Yes |
| RoHS Status | Non-compliant (contains lead, EPROM-era process) |
PIC16C622-20/SS Pin Configuration
| Pin 1 | RA2/AN2/VREF — Port A bit 2 / Comparator input / Voltage reference output |
| Pin 2 | RA3/AN3 — Port A bit 3 / Comparator input |
| Pin 3 | RA4/T0CKI — Port A bit 4 / Timer 0 clock input (open-drain) |
| Pin 4 | MCLR/VPP — Master clear reset (active low) / Programming voltage input |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — Port B bit 0 / External interrupt input |
| Pin 7 | RB1 — Port B bit 1 (digital I/O) |
| Pin 8 | RB2 — Port B bit 2 (digital I/O) |
| Pin 9 | RB3 — Port B bit 3 (digital I/O) |
| Pin 10 | RB4 — Port B bit 4 (interrupt-on-change) |
| Pin 11 | RB5 — Port B bit 5 (interrupt-on-change) |
| Pin 12 | RB6 — Port B bit 6 (interrupt-on-change) |
| Pin 13 | RB7 — Port B bit 7 (interrupt-on-change) |
| Pin 14 | VDD — Positive supply voltage (3.0 V to 6.0 V) |
| Pin 15 | OSC2/CLKOUT — Oscillator output / Clock output (Fosc/4) |
| Pin 16 | OSC1/CLKIN — Oscillator input / External clock input |
| Pin 17 | RA0/AN0 — Port A bit 0 / Comparator non-inverting input |
| Pin 18 | RA1/AN1 — Port A bit 1 / Comparator inverting input |
| Pin 19 | RA5/SS — Port A bit 5 (digital I/O) |
| Pin 20 | RA7 — Port A bit 7 (digital I/O) |
Typical Applications
PIC16C622-20/SS is suitable for 6 applications: Legacy Industrial Sensor Interface, Appliance Control Board, Security and Alarm Panel Controller, Automotive Body Electronics (Legacy), Simple Motor Speed Controller, Hobby and Educational Robotics.
Legacy Industrial Sensor Interface
The PIC16C622-20/SS's integrated analog comparator with programmable internal voltage reference makes it well-suited for legacy 4-20 mA sensor signal conditioning loops. The internal VREF module sets comparator threshold without external resistors, while 13 I/O pins interface to switch sensors, relay outputs, and isolated digital lines. Operating at 20 MHz with 200 ns instruction cycle, it samples analog thresholds in microseconds and triggers actuator responses deterministically. The 3.0-6.0 V supply range accepts both 3.3 V and 5 V industrial rails common in PLC and DCS retrofit installations.
Recommended
Appliance Control Board
The PIC16C622-20/SS is widely deployed in legacy washing-machine, dishwasher, and microwave control boards where the EPROM-based design was validated over decades of field operation. 13 I/O lines drive LED indicators, button matrix scans, triac-fired heater elements, and buzzer outputs. The 35-instruction RISC core simplifies code review for safety-critical appliances, while the brown-out reset protects against brown-out-induced latch-up during motor inrush. Migration to PIC16F628A-I/SS is recommended for new designs requiring field firmware updates.
Recommended
Security and Alarm Panel Controller
The PIC16C622-20/SS integrates the necessary peripherals for legacy wired alarm panels: 13 I/O lines scan PIR sensors, door/window contacts, and keypad matrix; the analog comparator detects line-cut tamper signals via voltage threshold; the watchdog timer resets the MCU on firmware lockup. EPROM technology ensures the security code cannot be field-modified, providing tamper resistance. The 3.5 KB program memory accommodates zone-monitoring state machines with up to 8 zones plus keypad decoder logic.
Recommended
Automotive Body Electronics (Legacy)
In pre-2000 automotive body control modules, the PIC16C622-20/SS served as a node controller for door locks, mirror adjustments, and lighting control. The 13 I/O lines drive MOSFET low-side switches for incandescent lamps and relay coils, while the comparator monitors battery voltage for brown-out detection. The 6.0 V absolute maximum tolerates load-dump transients typical of 12 V automotive electrical systems when paired with external TVS protection. Industrial-grade -20I/SS variant extends operating temperature to +85 °C for under-hood applications.
Recommended
Simple Motor Speed Controller
The PIC16C622-20/SS's 8-bit timer with prescaler generates PWM signals for brushed DC motor speed control in legacy fan, pump, and small appliance applications. The analog comparator implements back-EMF sensing for sensorless speed feedback, while the programmable VREF sets the overcurrent trip threshold for FET protection. At 20 MHz the PWM frequency reaches 78 kHz (8-bit) above the audible range, eliminating acoustic noise. Brown-out reset protects the motor driver during supply sag.
Recommended
Hobby and Educational Robotics
The PIC16C622-20/SS remains popular in university microcontroller courses and hobby robotics due to its simple 35-instruction RISC architecture and EPROM-windowed CERDIP variant (PIC16C622-20/JW) for student code iteration. The 13 I/O lines drive servo motors via software PWM, read ultrasonic sensors, and interface to character LCDs in 4-bit mode. The internal voltage reference simplifies analog sensor calibration without external components. Although flash-based PIC16F628 is preferred for new designs, EPROM parts teach fundamental one-time-programming concepts in CS/EE curricula.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C622-20/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F628A-20/SS | PIC16C622-20I/SS | PIC16C622-20E/SS | PIC16C621A-20/SS | PIC16F88-I/SS |
|---|---|---|---|---|---|---|
| Package | SSOP-20 | SSOP-20 - same | SSOP-20 - same | SSOP-20 - same | SSOP-20 - same | SSOP-20 - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Type | EPROM 3.5 KB | Flash 3.5 KB | EPROM 3.5 KB | EPROM 3.5 KB | EPROM 3.5 KB | Flash 7 KB |
| RAM | 128 B | 224 B | 128 B | 128 B | 128 B | 368 B |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Temperature | 0 C to +70 C (commercial) | 0 C to +70 C (commercial) | -40 C to +85 C (industrial) | -40 C to +125 C (extended) | 0 C to +70 C (commercial) | -40 C to +85 C (industrial) |
| Analog Comparator + VREF | 1 comparator + VREF module | 1 comparator + VREF module | 1 comparator + VREF module | 1 comparator + VREF module | 1 comparator (no VREF module) | 1 comparator + VREF + ADC 10-bit |
| RoHS Compliance | Non-compliant (leaded) | Compliant (lead-free) | Non-compliant (leaded) | Non-compliant (leaded) | Non-compliant (leaded) | Compliant (lead-free) |
| Supply Voltage Range | 3.0 V to 6.0 V | 3.0 V to 5.5 V | 3.0 V to 6.0 V | 3.0 V to 6.0 V | 3.0 V to 6.0 V | 2.0 V to 5.5 V |
Key Differentiators
- Integrated voltage reference module eliminates external components (vs PIC16C621A-20/SS)
- EPROM technology provides one-time-programmable security (vs PIC16F628A-20/SS)
- SSOP-20 footprint shared with flash-based PIC16F family (vs PIC16F88-I/SS)
Design Notes
EPROM parts require a UV-windowed CERDIP package for code erasure. The PIC16C622-20/SS in SSOP-20 is one-time-programmable only - any code bug requires physical replacement of the chip. For development iteration, use the CERDIP windowed variant (PIC16C622-20/JW) and erase with UV light (30 min at 12,000 uW/cm2). Production programmers must verify EPROM cell margins at VDD min (3.0 V) and VDD max (6.0 V) per the Microchip programming specification.
Estimated: At 20 MHz and 5 V supply with all peripherals active, the PIC16C622-20/SS draws approximately 10-15 mA typical operating current. Decoupling requires a 0.1 uF ceramic capacitor placed within 5 mm of the VDD pin and a 10 uF tantalum bulk capacitor on the supply rail. Brown-out reset must be enabled in the configuration word (BODEN bit) to protect data EEPROM from corruption during supply sag below 4.0 V. The MCLR pin requires a 10 kohm pull-up to VDD for reliable reset behavior.
The SSOP-20 package has a 0.65 mm pin pitch requiring fine-pitch PCB assembly capability. Recommended land pattern per IPC-7351 (SSOP standard density): pad width 0.40 mm, pad length 1.50 mm, pad pitch 0.65 mm. Stencil aperture should be 0.50 mm x 1.80 mm for adequate solder paste volume. The exposed center pad (if present in variant) requires thermal vias to inner ground plane for heat dissipation. Avoid running high-speed traces under the package to minimize capacitive coupling.
Place the external crystal or ceramic resonator within 5 mm of the OSC1 and OSC2 pins with short, symmetric traces to minimize parasitic capacitance and EMI radiation. For HS mode (20 MHz crystal), add 22-33 pF load capacitors from each oscillator pin to ground, selected per the crystal manufacturer's load capacitance specification. Guard the oscillator traces with a ground pour and keep digital switching signals (PORTB output drivers) at least 3 mm away to avoid frequency modulation.
Compliance Information
RoHS non-compliant due to lead-bearing termination typical of EPROM-era SSOP packages. Reach status not explicitly stated in available data. Not AEC-Q100 qualified (commercial/industrial grade only). For RoHS-compliant pin-compatible replacement, use PIC16F628A-I/SS or PIC16F88-I/SS.
