PIC16C662-20I/PQ - 8-Bit OTP MCU 7KB 33 I/O 20MHz | Microchip
MPN: PIC16C662-20I/PQ β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.95 | $8.95 |
| 10 | $8.06 | $80.60 |
| 100 | $7.16 | $716.00 |
| 500 | $6.45 | $3,225.00 |
| 1,000 | $5.74 | $5,740.00 |
PIC16C662-20I/PQ Overview
An 8-bit microcontroller (MCU) is a small, self-contained computer-on-a-chip integrating a CPU core, program memory, data RAM, and peripherals. The PIC16C family belongs to the broader hierarchy: microcontroller -> embedded controller -> semiconductor -> integrated circuit. Within that taxonomy, the PIC16C662 sits in the mid-range PIC16C family, providing OTP (One-Time-Programmable) program memory suitable for low-to-medium volume production where field upgrades are not required.
Key features include a RISC architecture with only 35 single-word instructions to learn, 8-bit data path, two analog comparators with programmable reference, 8-bit/16-bit timers, a synchronous serial port (SSP) supporting SPI and I2C, and a USART with addressable TX/RX buffers. All instructions execute in a single cycle except program branches, which take two cycles - yielding 5 MIPS performance at 20 MHz. The 33 I/O pins can sink/source up to 25 mA each, suitable for direct LED drive.
The device is built on Microchip's baseline-plus CMOS process with EPROM program memory, providing field-programmability during development and OTP production cost at volume. The integrated analog comparators eliminate the need for external comparators in many closed-loop control applications, while the SSP and USART enable communication with peripheral ICs and host processors.
Typical applications include industrial control logic, motor drive interface circuits, sensor signal conditioning, automotive body electronics, and embedded control subsystems. The wide industrial temperature range and 33 I/O make the PIC16C662-20I/PQ a flexible workhorse for designers building mid-range 8-bit control systems.
When designing with this MCU, plan OTP programming into the production flow since OTP memory cannot be erased. Provide adequate decoupling (100 nF + 10 uF) near VDD/AVDD pins, and observe the in-circuit serial programming (ICSP) timing specifications for production programming reliability.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives, and practical design notes for the PIC16C662-20I/PQ - information that goes beyond a single datasheet lookup.
Drop-in alternatives for PIC16C662-20I/PQ β 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 PIC16C662-20I/PQ (same form factor and footprint) β differing in Package, Program Memory Type, Program Memory Size, Analog Comparators, Communication Peripherals.
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Request AlternativesPIC16C662-20I/PQ Maximum Ratings & Electrical Characteristics
| Architecture | 8-bit RISC |
| Program Memory Type | OTP (One-Time-Programmable EPROM) |
| Program Memory Size | 7 KB (4K x 14) |
| RAM Size | 176 bytes |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle | 200 ns (single-cycle) |
| Supply Voltage Range | 4.5 V to 5.5 V |
| I/O Pins | 33 |
| Analog Comparators | 2 |
| Timers | 3 (Timer0 8-bit, Timer1 16-bit, Timer2 8-bit) |
| Communication Peripherals | SSP (SPI/I2C), USART/SCI |
| Operating Temperature Range | -40 C to +85 C (Industrial) |
| Package | 44-pin MQFP (PQ) |
| Mounting Type | Surface Mount |
| Instruction Set | 35 instructions |
| MIPS | 5 MIPS at 20 MHz |
| I/O Sink/Source Current | 25 mA per pin |
| Watchdog Timer | Yes (programmable WDT) |
| In-Circuit Programming | ICSP support |
PIC16C662-20I/PQ Pin Configuration
| Pin 1 | OSC1/CLKIN β Oscillator crystal input or external clock input |
| Pin 2 | OSC2/CLKOUT β Oscillator crystal output or clock output |
| Pin 3 | MCLR/VPP β Master clear reset or programming voltage input |
| Pin 4 | RA0/AN0 β PORTA bit 0 / analog comparator input |
| Pin 5 | RA1/AN1 β PORTA bit 1 / analog comparator input |
| Pin 6 | RA2/AN2/CVREF β PORTA bit 2 / analog comparator input / comparator voltage reference |
| Pin 7 | RA3/AN3/VREF+ β PORTA bit 3 / analog comparator input / positive voltage reference |
| Pin 8 | RA4/T0CKI β PORTA bit 4 / Timer0 clock input |
| Pin 9 | RA5/SS/AN4 β PORTA bit 5 / SPI slave select / analog comparator input |
| Pin 10 | VSS β Ground reference |
| Pin 11 | VDD β Positive supply voltage |
| Pin 12 | RB0/INT β PORTB bit 0 / external interrupt input |
| Pin 13 | RB1 β PORTB bit 1 |
| Pin 14 | RB2 β PORTB bit 2 |
| Pin 15 | RB3/PGM β PORTB bit 3 / low-voltage programming enable |
| Pin 16 | RB4 β PORTB bit 4 |
| Pin 17 | RB5 β PORTB bit 5 |
| Pin 18 | RB6/PGC β PORTB bit 6 / ICSP clock input |
| Pin 19 | RB7/PGD β PORTB bit 7 / ICSP data I/O |
| Pin 20 | VSS β Ground reference |
| Pin 21 | VDD β Positive supply voltage |
| Pin 22 | RC0/T1OSO/T1CKI β PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 23 | RC1/T1OSI/CCP2 β PORTC bit 1 / Timer1 oscillator input / CCP2 output |
| Pin 24 | RC2/CCP1 β PORTC bit 2 / CCP1 I/O |
| Pin 25 | RC3/SCK/SCL β PORTC bit 3 / SPI clock / I2C clock |
| Pin 26 | RC4/SDI/SDA β PORTC bit 4 / SPI data in / I2C data |
| Pin 27 | RC5/SDO β PORTC bit 5 / SPI data out |
| Pin 28 | RC6/TX/CK β PORTC bit 6 / USART async transmit / USART sync clock |
| Pin 29 | RC7/RX/DT β PORTC bit 7 / USART async receive / USART sync data |
| Pin 30 | VSS β Ground reference |
| Pin 31 | VDD β Positive supply voltage |
| Pin 32 | RD0 β PORTD bit 0 |
| Pin 33 | RD1 β PORTD bit 1 |
| Pin 34 | RD2 β PORTD bit 2 |
| Pin 35 | RD3 β PORTD bit 3 |
| Pin 36 | RD4 β PORTD bit 4 |
| Pin 37 | RD5 β PORTD bit 5 |
| Pin 38 | RD6 β PORTD bit 6 |
| Pin 39 | RD7 β PORTD bit 7 |
| Pin 40 | VSS β Ground reference |
| Pin 41 | VDD β Positive supply voltage |
| Pin 42 | RE0/RD β PORTE bit 0 / parallel slave port read control |
| Pin 43 | RE1/WR β PORTE bit 1 / parallel slave port write control |
| Pin 44 | RE2/CS β PORTE bit 2 / parallel slave port chip select |
Typical Applications
PIC16C662-20I/PQ is suitable for 6 applications: Industrial Control Logic, Motor Drive Interface, Sensor Signal Conditioning, Automotive Body Electronics, Embedded Subsystem Control, Building Automation.
Industrial Control Logic
The PIC16C662-20I/PQ's 33 I/O lines, 7KB OTP program memory, and integrated USART make it ideal for industrial control logic modules, including PLC remote I/O racks, conveyor sequencers, and machine-tool interlocks. The 5 MIPS throughput at 20 MHz handles PID loops and protocol stacks, while the two analog comparators simplify closed-loop feedback without external op-amps. Its industrial -40C to +85C rating suits factory-floor enclosures without additional thermal conditioning. Program the device once at production via ICSP and field-proven OTP reliability keeps maintenance interventions minimal.
Recommended
Motor Drive Interface
The PIC16C662-20I/PQ is well suited as the control front-end for brushed DC and stepper motor drivers, where its 25 mA I/O drive directly interfaces with opto-couplers and small relay coils, while the PWM-friendly Timer2 module generates variable duty-cycle control signals. The 16-bit Timer1 enables precise velocity measurement via quadrature encoders, and the dual analog comparators allow current-limit detection on the H-bridge return path. Industrial temperature rating supports under-hood and motor cabinet environments.
Recommended
Sensor Signal Conditioning
For sensor signal conditioning, the PIC16C662-20I/PQ's two on-chip analog comparators allow direct interfacing with thermocouples, photodiodes, and Hall-effect sensors without external op-amps, while its SSP peripheral supports SPI or I2C digital sensors like accelerometers and pressure transducers. The 35-instruction RISC core executes averaging and linearization routines in real time at 20 MHz. The 33 I/O lines are sufficient to multiplex multiple sensor channels and drive status LEDs in a single compact 44-pin MQFP footprint.
Recommended
Automotive Body Electronics
The PIC16C662-20I/PQ serves well in cabin-level automotive body modules such as seat controllers, mirror adjusters, and lighting dimmers, where its 25 mA I/O directly drives small relays and LED arrays without buffer transistors. The industrial temperature range covers automotive cabin conditions. However, for under-hood AEC-Q100 qualified applications, Microchip recommends migrating to the PIC18F family. The 7KB OTP memory holds body-control state machines and CAN-style message handlers, with the USART enabling LIN bus communication via external transceiver.
Recommended
Embedded Subsystem Control
The PIC16C662-20I/PQ functions as an intelligent peripheral controller in larger embedded systems, handling key-scan matrices, display multiplexing, and keypad debounce while communicating with the host processor via SPI or USART. Its 176 bytes of RAM and 7KB OTP are adequate for menu-driven human-interface logic, while 33 I/O easily drives 4x5 keypads and 7-segment LED displays. The MQFP-44 package fits compact handheld enclosures, and the industrial temperature rating supports outdoor consumer electronics.
Recommended
Building Automation
In building automation subsystems such as HVAC damper controllers, access control keypads, and lighting ballast interfaces, the PIC16C662-20I/PQ delivers reliable 8-bit control at low cost. The 7KB OTP accommodates Modbus RTU or BACnet-style protocol handlers, while the dual analog comparators process thermistor and LDR inputs directly. The 33 I/O drive TRIAC optocouplers and zero-cross detectors, and the 5 MIPS throughput handles multiple channel scans. Industrial temperature operation supports unheated equipment closets and rooftop unit installations.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C662-20I/PQ β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C662-20I/PT | PIC16C662-20I/L | PIC16C662-20/PQ | PIC16C662-20E/PQ | PIC16F877-20I/PQ |
|---|---|---|---|---|---|---|
| Package | 44-pin MQFP (PQ) | 44-pin TQFP (PT) - similar | 44-pin PLCC (L) - differs | 44-pin MQFP (PQ) - same | 44-pin MQFP (PQ) - same | 44-pin MQFP (PQ) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Program Memory Type | OTP (7 KB) | OTP (7 KB) | OTP (7 KB) | OTP (7 KB) | Flash (14 KB) | |
| Temperature Range | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | 0 C to +70 C (Commercial) | -40 C to +125 C (Extended) | -40 C to +85 C (Industrial) | |
| RAM Size | 176 bytes | 176 bytes | 176 bytes | 368 bytes | ||
| I/O Pins | 33 | 33 | 33 | 33 | ||
| Analog Comparators | 2 | 2 | 2 | 2 + 10-bit ADC | ||
| Lifecycle Status | NRND | NRND | NRND | Active | ||
| Qty-1 Unit Price (USD, as of 2026-09-18) | $8.95 | $9.20 | $7.85 | $9.50 |
Key Differentiators
- Industrial temperature grade in MQFP package (vs PIC16C662-20/PQ)
- Dual analog comparators with programmable reference (vs PIC16F877-20I/PQ)
- Single 5V supply operation simplifies design (vs PIC16C662-04I/PQ)
- OTP memory for production cost efficiency (vs PIC16F877-20I/PQ)
Design Notes
Decouple each VDD pin (pins 11, 21, 31, 41) with a 100 nF ceramic capacitor placed within 5 mm of the IC pin, and add a single 10 uF bulk tantalum or ceramic capacitor near the device. The PIC16C662 draws approximately 15 mA active at 20 MHz; ensure the 5V regulator can source the I/O sum plus core current. The analog comparator inputs benefit from a clean AVDD separate from the digital VDD when used for precision thresholding.
Because the PIC16C662 program memory is OTP, every firmware revision requires a fresh device. Plan OTP device inventory carefully, and use a windowed CERQUIN package (PIC16C662-20/JW) for prototype development. The MCLR/VPP pin must be pulled up through a resistor (typically 10 kOhm) and have a 100 nF capacitor for power-on-reset; do not leave it floating.
Place the 20 MHz crystal or resonator close to OSC1 (pin 1) and OSC2 (pin 2), with short, symmetric traces to minimize parasitic capacitance. The MQFP-44 package has a thermal pad which should be soldered to a copper pour on the PCB for improved heat dissipation - though power dissipation is modest, the thermal pad reduces ground bounce. Keep analog comparator traces (RA0-RA3) away from high-current digital switching lines.
When using the USART at high baud rates with long PCB traces, add a series resistor (22-100 Ohm) near the TX pin to dampen ringing. For SPI, observe the 33 pF maximum load specification and use a buffer if driving multiple slaves. The I2C bus requires pull-up resistors (typically 4.7 kOhm at 400 kHz) and benefits from a buffer when cable lengths exceed 30 cm.
Compliance Information
Compliance data not provided in the verified web data; verify with Microchip's product compliance declarations. The part is industrial temperature rated but not AEC-Q100 qualified - for automotive under-hood use, migrate to PIC18F family.
