PIC16C620AT-20/SS - 8-Bit OTP MCU 20MHz 896B SSOP-20 | Microchip
MPN: PIC16C620AT-20/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.42 | $3.42 |
| 10 | $3.07 | $30.70 |
| 100 | $2.74 | $274.00 |
| 500 | $2.45 | $1,225.00 |
| 1,000 | $2.18 | $2,180.00 |
PIC16C620AT-20/SS Overview
A microcontroller (MCU) is a single-chip computer containing a processor core, program memory, data memory, and integrated peripherals. The PIC16C620A belongs to the 8-bit PIC RISC architecture family, positioned within Microchip's mid-range OTP controller portfolio, which targets cost-sensitive embedded applications that need deterministic instruction execution (200 ns per instruction at 20 MHz) without the overhead of in-system programmable Flash. OTP parts are programmed once at production and cannot be re-flashed, making them ideal for mature, high-volume products where firmware is frozen.
Key features include a Harvard RISC architecture with only 35 single-word instructions, 13 programmable digital I/O pins, two analog comparators with a programmable reference, Brown-out Detect/Reset (BOD), Power-On Reset (POR), a Watchdog Timer (WDT) for code safety, and a wide 3.0 V to 5.5 V operating range. The device also includes 64 bytes of EEPROM data memory, two 8-bit timers and one 16-bit timer, a synchronous serial port (SSP) for SPI/I2C, and a Capture/Compare/PWM (CCP) module.
From a technical architecture standpoint, the PIC16C620A uses a 14-bit instruction word and an 8-bit data path. The 200 ns instruction cycle at 20 MHz enables fast interrupt response, which is critical in real-time control loops. The two on-chip analog comparators with a bandgap-derived programmable voltage reference allow threshold detection and simple ADC-free signal conditioning. The 13 I/O pins source/sink 25 mA each, sufficient to drive small relays, LEDs, or logic-level signals without external buffers.
Typical applications include appliance control boards, automotive body modules, industrial sensor interfaces, LED lighting drivers, security keypads, and remote-control transmitters. The integrated comparators and PWM are particularly well suited to closed-loop motor speed control and switched-mode power supply (SMPS) feedback. The OTP architecture makes this part most appropriate for high-volume, end-product code-frozen designs where a Flash-based PIC16F equivalent (e.g., PIC16F628A) is over-specified and more expensive.
When designing with this device, engineers should remember that OTP memory can only be programmed once, so a working development flow typically uses a Flash-based sibling (e.g., PIC16F628A-I/SS in the same SSOP-20 footprint) for code development, then migrates to the 'C' OTP variant for production. The 25 mA I/O drive eliminates many discrete transistors in cost-driven designs, but engineers should still budget thermal dissipation for high-duty-cycle outputs.
This page synthesizes distributor pricing, same-package drop-in alternatives, application recommendations, and practical design notes for the PIC16C620AT-20/SS in a single, citable reference not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC16C620AT-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 PIC16C620AT-20/SS (same form factor and footprint) — differing in Program Memory Size, Operating Temperature, Program Memory Type, Timers, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C620A-20I/SS
✅ Drop-In✓ In Stock
$2.15 / Unit
View Datasheet →PIC16C620A-20E/SS
✅ Drop-In✓ In Stock
$1.62 / Unit
View Datasheet →PIC16C620A-04I/SS
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →PIC16C620-20/SS
✅ Drop-In✓ In Stock
$2.41 / Unit
View Datasheet →PIC16F628A-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C621A-20/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C620AT-20/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC16C RISC |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 896 B (512 x 14-bit words) |
| Data RAM | 96 B |
| Data EEPROM | 64 B |
| Maximum CPU Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns @ 20 MHz |
| Operating Voltage | 3.0 V to 5.5 V |
| Number of I/O Pins | 13 |
| I/O Pin Drive Strength | 25 mA source/sink |
| Analog Comparators | 2 with programmable reference |
| Timers | 2 x 8-bit, 1 x 16-bit |
| CCP Module | Capture/Compare/PWM x1 |
| Serial Interface | SSP (SPI / I2C) |
| Peripherals | Brown-out Detect, Power-On Reset, Watchdog Timer |
| Package Type | 20-pin SSOP (0.209", 5.30 mm width) |
| Operating Temperature | 0 C to +70 C (commercial, T suffix = tape & reel) |
| Mounting Type | Surface Mount |
PIC16C620AT-20/SS Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (Reset) input / programming voltage |
| Pin 2 | RA0/AN0 — Port A bit 0 / analog input 0 |
| Pin 3 | RA1/AN1 — Port A bit 1 / analog input 1 |
| Pin 4 | RA2/AN2/VREF — Port A bit 2 / analog input 2 / comparator VREF |
| Pin 5 | RA3/AN3 — Port A bit 3 / analog input 3 |
| Pin 6 | RA4/T0CKI — Port A bit 4 / Timer 0 clock input (open-drain) |
| Pin 7 | RA5/SS/AN4 — Port A bit 5 / SSP slave select / analog input 4 |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 10 | OSC2/CLKOUT — Oscillator crystal output / clock output |
| Pin 11 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer 1 oscillator output / T1 clock input |
| Pin 12 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer 1 oscillator input / CCP2 |
| Pin 13 | RC2/CCP1 — Port C bit 2 / CCP1 PWM/capture/compare |
| Pin 14 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 15 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 16 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 17 | RC6 — Port C bit 6 |
| Pin 18 | RC7 — Port C bit 7 |
| Pin 19 | VDD — Positive supply (3.0-5.5 V) |
| Pin 20 | RB7/PGM — Port B bit 7 / low-voltage programming input |
Typical Applications
PIC16C620AT-20/SS is suitable for 6 applications: Appliance Control Boards, Automotive Body Electronics, Industrial Sensor Signal Conditioning, LED Lighting Drivers, Security Keypads and Access Panels, Remote Control Transmitters.
Appliance Control Boards
The PIC16C620AT-20/SS fits appliance control boards because of its 25 mA I/O drive (enough for relay coils and triac gates without external buffers), 3.0-5.5 V single-supply operation, and 20 MHz core that handles timing-critical washing-machine, dishwasher, or microwave-oven state machines. The integrated two analog comparators with programmable VREF close temperature-sensor feedback loops directly, replacing a discrete op-amp + reference design. The OTP architecture and 13 I/O pins keep BOM cost low for high-volume white goods, where firmware is frozen at production. Typical circuits place the MCU at the heart of the user-interface board, reading keypad rows, driving 7-segment displays, and gating a triac through an opto-isolator.
Recommended
Automotive Body Electronics
The PIC16C620AT-20/SS serves automotive body-control modules such as mirror adjusters, seat-position controllers, and ambient-light sensors thanks to its Brown-out Detect and Watchdog Timer, which provide the supervisory safety features required in 12 V vehicle electrical environments. The two analog comparators convert PWM-dimmable ambient light into a digital brightness level without an external ADC. The 20 MHz instruction cycle and 8-bit PIC RISC architecture support deterministic loop times in mirror-folding and seat-memory actuators. Engineers typically derate to industrial-grade siblings (e.g., PIC16C620A-20I/SS) for under-hood applications, but the commercial-grade 'T' version fits cabin electronics within 0 to +70 C envelope.
Recommended
Industrial Sensor Signal Conditioning
The PIC16C620AT-20/SS conditions industrial sensor signals using its on-chip analog comparators with programmable VREF, which threshold-detect 4-20 mA loops, thermistor bridges, and Hall-effect sensors without external op-amps. The 13 I/O pins multiplex multiple sensor inputs to a single MCU, while the 20 MHz core runs the linearization and filtering math in real time. The integrated CCP module generates PWM excitation for ratiometric sensors. Because the OTP part cannot be re-flashed, it suits mature fixed-setpoint designs (e.g., level switches, photoelectric sensors) where firmware is stable across the product lifetime.
Recommended
LED Lighting Drivers
The PIC16C620AT-20/SS drives LED lighting strings using its CCP module to generate high-resolution PWM dimming at 20 MHz, allowing smooth 0-100 percent brightness control without external LED-driver ICs. The 25 mA I/O drive directly interfaces with low-current LED chains or gates a MOSFET for high-current strips. The two analog comparators with VREF sense ambient light for daylight harvesting, replacing a dedicated light-to-frequency IC. The 3.0-5.5 V supply range accepts USB-powered or 5 V adapter inputs directly, simplifying the power tree in decorative and architectural LED fixtures.
Recommended
Security Keypads and Access Panels
The PIC16C620AT-20/SS powers security keypads and access-control panels by scanning 4x4 matrix keypads with its 13 I/O pins (8 I/O suffice for 4x4, leaving pins for LED feedback and buzzer drive), debouncing inputs, and verifying PINs in firmware. The 96-byte RAM stores recent-entry buffers, while the 896-byte OTP holds the access-control algorithm. The Brown-out Detect ensures clean reset on power glitches, preventing false unlocks during brownouts. The Watchdog Timer recovers from firmware lockup due to EMI, a common concern in security installations near power lines.
Recommended
Remote Control Transmitters
The PIC16C620AT-20/SS fits low-power remote-control transmitters (garage-door openers, RF key fobs, IR remote controllers) because of its low-cost OTP, 20 MHz execution, and the 13 I/O pins that drive encoder ICs or directly key an RF/IR modulator. The Watchdog Timer provides firmware sanity, and the 3.0-5.5 V supply accepts 2x AA / coin-cell boost outputs. The PIC16C620A's small code footprint (896 B) easily holds rolling-code or fixed-code algorithms. For battery-powered designs, the CCP PWM generates precise carrier frequencies (e.g., 38 kHz IR, 433 MHz SAW-stabilized RF) directly from the timer.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C620AT-20/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C620A-20I/SS | PIC16C620A-20E/SS | PIC16C620A-04I/SS | PIC16C620-20/SS | PIC16F628A-I/SS |
|---|---|---|---|---|---|---|
| Package | SSOP-20 (0.209", 5.30 mm) | 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 | OTP (896 B / 512 x 14) | Windowed EPROM | OTP | OTP | OTP | Flash (re-programmable) |
| Maximum CPU Frequency | 20 MHz | 20 MHz | 20 MHz | 4 MHz | 20 MHz | 20 MHz |
| Data RAM | 96 B | 96 B | 96 B | 96 B | 96 B | 224 B |
| Operating 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 |
| Temperature Grade | 0 C to +70 C (commercial) | -40 C to +85 C (industrial) | -40 C to +125 C (extended) | -40 C to +85 C (industrial) | 0 C to +70 C (commercial) | -40 C to +85 C (industrial) |
| Number of I/O Pins | 13 | 13 | 13 | 13 | 13 | 16 |
Key Differentiators
- Drop-in Flash development path with PIC16F628A-I/SS (vs PIC16F628A-I/SS)
- Higher 20 MHz CPU clock than 04 MHz sibling (vs PIC16C620A-04I/SS)
- Commercial 0-70 C vs industrial -40 to +85 C (vs PIC16C620A-20I/SS)
Design Notes
Decouple VDD (pin 19) with a 0.1 uF ceramic capacitor placed within 5 mm of the pin, and add a bulk 10 uF tantalum or aluminum electrolytic at the board supply input. The PIC16C620A core draws a few mA at 20 MHz plus I/O switching transients, so inadequate decoupling causes code-fetch glitches and Brown-out Resets. For battery-powered applications, the internal Brown-out Reset and Watchdog Timer together eliminate the need for an external supervisor IC, saving cost and board area.
OTP memory can only be programmed once - there is no second chance. Use a PIC16F628A-I/SS (Flash, same SSOP-20 footprint) as the development platform, verify the firmware, then migrate to PIC16C620AT-20/SS for production. Verify the MCLR/VPP pin is correctly pulled up through a 10 kohm resistor; floating MCLR causes random resets. The 'T' suffix is tape-and-reel packaging only and does not change silicon - so do not confuse it with a part-number difference during sourcing.
Route the oscillator traces (OSC1/OSC2, pins 9-10) short and symmetrical, with the crystal/capacitor pair within 5 mm of the pins. Keep digital switching traces (Port B, CCP outputs) away from the analog comparator inputs (RA0-RA3) to avoid noise injection into the threshold reference. The SSOP-20 footprint is pin-compatible with PIC16F628A, allowing a single PCB to accept either MCU during engineering build phases - hand-solder with a fine tip and no-clean flux paste.
Compliance Information
Compliance status not explicitly stated in the verified web data. PIC16C620A family parts are commonly supplied in lead-free / RoHS-compliant packaging per Microchip policy, but specific compliance for this MPN should be confirmed with the manufacturer before use in regulated applications.
