PIC16C620A-04/SO - 8-Bit OTP MCU, 4MHz, 896B, 18-SOIC | Microchip
MPN: PIC16C620A-04/SO ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.95 | $2.95 |
| 10 | $2.66 | $26.60 |
| 100 | $2.21 | $221.00 |
| 500 | $1.9 | $950.00 |
| 1,000 | $1.62 | $1,620.00 |
PIC16C620A-04/SO Overview
A microcontroller (microcontroller unit, MCU) is a single-chip computer that integrates a CPU core, non-volatile program memory, working RAM, and peripheral interfaces (I/O, timers, ADC, communication). It sits below microprocessor in the embedded hierarchy: MCU -> 8-bit microcontroller -> PIC microcontroller -> Microchip PIC16 family. Unlike Flash-based MCUs, the OTP variant is programmed once at production and cannot be reprogrammed, making it suited for cost-sensitive, high-volume fixed-function products.
Key specifications include a 4 MHz maximum oscillator frequency, 2.0V to 6.0V operating voltage range, 13 I/O pins, two 8-bit timers plus one 16-bit timer, and a 10-bit resolution capture/compare/PWM module. The part includes an internal watchdog timer, power-on reset, brown-out reset, and 13 interrupt sources. It supports In-Circuit Serial Programming (ICSP) through two pins.
The PIC16C620A-04 uses a Harvard RISC architecture with separate program and data buses, providing deterministic 200 ns instruction execution at 4 MHz. Its CMOS OTP process delivers low power consumption (typically < 2 mA at 5V/4 MHz) and industrial-grade ESD protection. The 18-pin SOIC package offers a 7.87 mm body width suitable for hand-soldering and standard SMT lines.
Typical applications include appliance control boards, sensor signal conditioning, simple motor drives, and remote-control transmitters. It is also widely used as a pin-compatible upgrade for the older PIC16C620 in industrial control retrofits and educational kits where OTP cost savings outweigh in-field reprogrammability.
Design consideration: OTP memory cannot be re-written, so firmware verification must be done on a pre-programmed sample or a Flash equivalent (PIC16F62X) before committing to production volumes. Always validate timing in the worst-case instruction cycle (200 ns = 5 MIPS equivalent at 4 MHz).
This page synthesizes distributor pricing, drop-in same-package alternatives, and engineering design notes not consolidated on the manufacturer datasheet, helping procurement and design engineers evaluate the PIC16C620A-04/SO for both new designs and legacy replacements.
Drop-in alternatives for PIC16C620A-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 PIC16C620A-04/SO (same form factor and footprint) — differing in RoHS Status, Program Memory Size, Program Memory Type, Package, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C620-04I/SO
✅ Drop-In✓ In Stock
$1.65 / Unit
View Datasheet →PIC16C620-04/SS
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.2 / Unit
View Datasheet →PIC16C620A-04I/SO
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →PIC16C620-20E/SO
✅ Drop-In✓ In Stock
$3.3 / Unit
View Datasheet →PIC16C620-20/SO
✅ Drop-In✓ In Stock
$2.52 / Unit
PIC16C620A-04/SO Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology |
| Series | PIC® 16C |
| Core Processor | PIC |
| Core Size | 8-Bit |
| Maximum Clock Frequency | 4 MHz |
| Instruction Cycle Time | 200 ns |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 896 B (512 x 14) |
| RAM Size | 96 B |
| Number of I/O Pins | 13 |
| Operating Voltage Range | 2.0 V to 6.0 V |
| Number of Instructions | 35 |
| Timers | 1 x 8-bit, 1 x 16-bit |
| Watchdog Timer | Yes |
| Brown-out Reset / POR | Yes |
| ICSP Programming | Yes (2-wire) |
| Package | 18-SOIC (7.50 mm body width) |
| Mounting Type | Surface Mount |
| Operating Temperature Range | 0 °C to +70 °C (commercial) |
| RoHS Status | Compliant (per DigiKey listing) |
PIC16C620A-04/SO Pin Configuration
| Pin 1 | RA2/AN2 — PORTA bit 2 / analog comparator input |
| Pin 2 | RA3/AN3 — PORTA bit 3 / analog comparator input |
| Pin 3 | RA4/T0CKI — PORTA bit 4 (open-drain) / Timer0 clock input |
| Pin 4 | RA5/MCLR/VPP — PORTA bit 5 / Master Clear (reset) / programming voltage input |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — PORTB bit 0 / external interrupt |
| Pin 7 | RB1 — PORTB bit 1 |
| Pin 8 | RB2 — PORTB bit 2 |
| Pin 9 | RB3 — PORTB bit 3 |
| Pin 10 | RB4 — PORTB bit 4 |
| Pin 11 | RB5 — PORTB bit 5 |
| Pin 12 | RB6 — PORTB bit 6 / ICSP clock |
| Pin 13 | RB7 — PORTB bit 7 / ICSP data |
| Pin 14 | VDD — Positive supply (2.0V to 6.0V) |
| Pin 15 | OSC2/CLKOUT — Oscillator output / clock out |
| Pin 16 | OSC1/CLKIN — Oscillator input / external clock in |
| Pin 17 | RA0/AN0 — PORTA bit 0 / analog comparator input |
| Pin 18 | RA1/AN1 — PORTA bit 1 / analog comparator input |
Typical Applications
PIC16C620A-04/SO is suitable for 6 applications: Appliance Control Board, Remote Control Transmitter, Sensor Signal Conditioning Front-End, Simple Motor Driver Control, Educational Microcontroller Trainer, LED Display Driver Board.
Appliance Control Board
The PIC16C620A-04/SO fits low-cost appliance control boards (washing machines, microwave ovens, rice cookers) where the firmware is fixed at production and unit cost dominates BOM. With 13 digital I/O driving relays, triacs and 7-segment LED displays, plus two timers for washing-cycle sequencing, the part handles motor and heater timing without external counters. Its 2.0V-6.0V supply range tolerates rectified mains drops, and the 96B RAM is sufficient for state-machine cycle tracking. The 4 MHz instruction cycle is fast enough for zero-crossing triac control at 50/60 Hz mains. Compared to a Flash MCU, OTP saves roughly USD 0.30 per unit at 100k volumes, which compounds across high-volume appliance SKUs.
Recommended
Remote Control Transmitter
Handheld IR/RF remote controls benefit from the PIC16C620A-04/SO's low active current (under 2 mA at 5V/4 MHz), 13 I/O for keypad matrix scanning, and OTP cost savings on millions of disposable units. The CCP module generates 38 kHz carrier for IR modulation, and the 16-bit timer times out long press detection. Because remote firmware rarely changes after qualification, OTP is a deliberate choice that eliminates the Flash write/erase wear concern. Brown-out reset and watchdog timer are essential for battery-low lockup recovery. Designers should reserve pin RA4 (open-drain) for the wake-up interrupt on a tactile button to wake the part from sleep.
Recommended
Sensor Signal Conditioning Front-End
Industrial sensor front-ends use the PIC16C620A-04/SO to read analog comparators on PORTA, debounce mechanical switches, and output conditioned logic to a downstream PLC or display. The two analog comparators on PORTA multiplex with digital I/O, allowing direct thermistor or photocell interfacing without an external op-amp. The 13 I/O can drive a small character LCD or 7-segment display. Brown-out reset prevents sensor misreading during supply dips, and the watchdog timer recovers from ESD-induced firmware lockup. OTP is appropriate because the calibration coefficients are burned once at factory test, not at field deployment.
Recommended
Simple Motor Driver Control
Low-cost BLDC or stepper motor controllers use the PIC16C620A-04/SO to generate step pulses and direction signals for external MOSFET drivers. The 16-bit timer creates precise step rates from sub-Hz to tens of kHz, while the 13 I/O drive step, direction, enable, and limit-switch inputs. At 4 MHz the part produces step pulses down to 200 ns resolution, adequate for microstepping controllers when paired with an external driver. OTP keeps the firmware locked against field tampering in consumer-grade 3D printers and CNC accessories. Designers should add external flyback diodes on inductive loads and follow Microchip's PCB layout guidelines for the SOIC power/ground pins.
Recommended
Educational Microcontroller Trainer
Universities and electronics training kits favor the PIC16C620A-04/SO for teaching 8-bit embedded design because of its 35-instruction RISC core, transparent timing, and breadboard-friendly 18-SOIC footprint (paired with an SOIC-to-DIP adapter). Students learn timer/counter basics, GPIO control, and interrupt handling with a 200 ns instruction budget visible at 4 MHz. Although OTP prevents student rewrites in production PCBs, Flash equivalents like PIC16F627/628A can be used on the same trainer PCB for in-class firmware experiments. The wide 2.0V-6.0V supply range simplifies benchtop power supply designs and battery experiments.
Recommended
LED Display Driver Board
Scoreboards, signage controllers and decorative LED chains use the PIC16C620A-04/SO as a fixed-pattern LED driver. With 13 I/O the part can drive a 7-segment digit, 8x8 matrix row/column, or WS2811-style addressable LED data line via bit-banging. The 4 MHz clock is sufficient for WS2811 800 kHz protocol when the ISR is tuned. Brown-out reset prevents LED ghosting on power-up. OTP is ideal because the LED patterns are locked at production and never change, eliminating Flash bit-cost. For designs that need addressable LEDs at higher refresh, PIC16F628A at 20 MHz is the recommended Flash upgrade.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C620A-04/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C620-04I/SO | PIC16C620-04/SS | PIC16C620A-04I/SO | PIC16C620-20E/SO | PIC16C620-20/SO |
|---|---|---|---|---|---|---|
| Package | 18-SOIC | 18-SOIC (same) | 18-SSOP (same pin count, smaller body) | 18-SOIC (same) | 18-SOIC (same) | 18-SOIC (same) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Maximum Clock Frequency | 4 MHz | 4 MHz (same) | 4 MHz (same) | 4 MHz (same) | 20 MHz (+400%) | 20 MHz (+400%) |
| Program Memory | 896 B OTP | 896 B OTP (same) | 896 B OTP (same) | 896 B OTP (same) | 896 B OTP (same) | 896 B OTP (same) |
| RAM Size | 96 B | 96 B (same) | 96 B (same) | 96 B (same) | 96 B (same) | 96 B (same) |
| Operating Temperature | 0 °C to +70 °C (commercial) | -40 °C to +85 °C (industrial) | 0 °C to +70 °C (same) | -40 °C to +85 °C (industrial) | -40 °C to +125 °C (extended) | 0 °C to +70 °C (same) |
| Number of I/O Pins | 13 | 13 (same) | 13 (same) | 13 (same) | 13 (same) | 13 (same) |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete |
| Instruction Set | 35-instruction mid-range PIC | 35-instruction mid-range PIC (same) | 35-instruction mid-range PIC (same) | 35-instruction mid-range PIC (same) | 35-instruction mid-range PIC (same) | 35-instruction mid-range PIC (same) |
Key Differentiators
- Industry-standard 35-instruction mid-range PIC core with 200 ns deterministic instruction cycle at 4 MHz (vs PIC16C620-04I/SO)
- Same 18-SOIC pinout and 896 B OTP memory across the family, allowing direct BOM substitution (vs PIC16F627 (Flash equivalent))
- Built-in analog comparators on RA0-RA3 enable direct sensor interfacing without external op-amps (vs PIC16C620-04/SS (18-SSOP))
Design Notes
Decouple VDD (pin 14) and VSS (pin 5) with a 100 nF ceramic capacitor placed within 5 mm of the package pins, plus a bulk 10 µF tantalum or aluminum electrolytic on the same supply rail. The PIC16C620A-04/SO draws less than 2 mA active at 5V/4 MHz, but the bulk capacitor prevents supply droop during the in-rush of relay drivers that share the rail. Tie the MCLR/VPP pin (pin 4) to VDD through a 10 kΩ resistor for normal operation, or drive it from the ICSP programmer for code download. Adding a 100 nF capacitor from MCLR to VSS improves reset noise immunity.
Because PIC16C620A-04/SO is OTP memory, no field firmware updates are possible after the device is programmed. Validate firmware on a Flash sibling such as PIC16F627 first, then commit OTP volumes only when firmware is locked. Pin 4 (RA5/MCLR/VPP) is shared between digital I/O, master clear reset, and programming voltage; if used as an output it cannot be re-entered as MCLR without disabling the reset feature in configuration bits. Pin 3 (RA4) is open-drain and requires an external pull-up if used as an output, or it will only sink current.
Route the ICSP clock (RB6, pin 12) and ICSP data (RB7, pin 13) traces to a 6-pin header with no series resistors above 100 Ω, to allow production programming access on every PCB. Keep the oscillator traces (OSC1/OSC2, pins 16 and 15) short and surround them with a ground guard ring, particularly when using a crystal rather than an external clock. The 18-SOIC thermal pad is not present on this package, so no central copper pour is required; standard 1 oz copper on signal layers suffices for the sub-2 mA load.
For designs that bit-bang the WS2811 or similar addressable LED chain, ensure the ISR rate plus instruction budget leaves at least 200 ns of margin at 4 MHz. A tight loop of 4 instructions yields an 800 ns pulse, well within the 800 kHz WS2811 timing, but any branch in the loop will exceed timing. Place a ferrite bead on the +5V rail feeding WS2811 chains to suppress switching transients back into the PIC16C620A's analog comparator inputs on PORTA.
Compliance Information
RoHS and lead-free status per DigiKey listing for PIC16C620A-04/SO. Part is not AEC-Q100 qualified; PIC16C620 family is not designed for automotive safety-critical applications.
