PIC16C662-20/PQ - 8-bit OTP MCU, 7KB, 33 I/O, 20MHz | Microchip
MPN: PIC16C662-20/PQ ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $14.5 | $14.50 |
| 10 | $13.2 | $132.00 |
| 100 | $11.95 | $1,195.00 |
| 500 | $10.8 | $5,400.00 |
| 1,000 | $9.75 | $9,750.00 |
PIC16C662-20/PQ Overview
A microcontroller (MCU) is a single-chip computer that contains a processor core, program memory, working RAM, and peripheral interfaces. Within the broader taxonomy, the PIC16C662 belongs to the 8-bit MCU category, which sits beneath the umbrella of microcontrollers, embedded processors, and ultimately semiconductor ICs. 8-bit MCUs remain dominant in cost-sensitive, deterministic control applications where their simple Harvard architecture and predictable instruction timing are advantageous over 32-bit Cortex-M alternatives.
Key features include 7KB of OTP program memory for field-programmable but non-rewritable code storage, 33 general-purpose I/O pins with individual direction control, a 20 MHz oscillator input that yields a 5 MHz instruction cycle (one instruction per four oscillator cycles), and a brown-out reset circuit. The integrated 10-bit ADC provides up to 8 analog input channels for direct sensor interfacing without external converters.
The PIC16C662 uses Microchip's mid-range RISC architecture with 35 single-word instructions and a 14-bit instruction word. Its OTP program memory makes it well suited to mature, high-volume production where firmware changes are no longer anticipated, whereas flash-based PIC16F6x family members are typically preferred during development and low-volume runs. The PQ suffix designates the 44-pin Metric Quad Flat Pack (MQFP) package, which supports surface-mount assembly.
Typical applications include industrial control panels, appliance controllers, automotive body electronics, uninterruptible power supplies, and embedded sensor hubs. The 33 I/O count, integrated USART, and CCP peripheral make it a strong fit for closed-loop motor control, switch-mode power supply secondary-side control, and HVAC damper/valve actuation.
When designing with the PIC16C662-20/PQ, note that OTP memory cannot be reprogrammed - all firmware must be fully validated before device programming. Decoupling capacitors of 100 nF should be placed adjacent to each VDD/VSS pair, and unused I/O pins should be configured as outputs to minimize quiescent current. This page synthesizes distributor stock data, drop-in same-family alternatives, and practical design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for PIC16C662-20/PQ — 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 PIC16C662-20/PQ (same form factor and footprint) — differing in Package, Program Memory Type, RoHS Status, Mounting Type, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C662-10E/L
✅ Drop-In✓ In Stock
$9.85 / Unit
View Datasheet →PIC16C662-10/P
✅ Drop-In✓ In Stock
$5.3 / Unit
View Datasheet →PIC16C662-04I/P
✅ Drop-In✓ In Stock
$5.07 / Unit
View Datasheet →PIC16C65B-04I/PQ
✅ Drop-In✓ In Stock
$5.45 / Unit
View Datasheet →PIC16C65B-04E/PQ
✅ Drop-In✓ In Stock
$11.1 / Unit
View Datasheet →PIC16C64A-20/PQ
✅ Drop-In✓ In Stock
$5.2 / Unit
View Datasheet →PIC16C662-20/PQ Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology |
| Series | PIC16C6x |
| Core | PIC16 |
| Core Size | 8-bit |
| Program Memory Type | OTP |
| Program Memory Size | 7 KB |
| RAM Size | 176 bytes |
| Number of I/O Pins | 33 |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns |
| ADC Resolution | 10-bit |
| ADC Channels | 8 |
| Supply Voltage (VDD) | 4.0 V to 6.0 V |
| Operating Temperature | 0 C to +70 C |
| Package | 44-pin MQFP (PQ) |
| Mounting Type | Surface Mount |
| Peripherals | USART, CCP, WDT, POR, BOR |
| Data EEPROM | None (OTP only) |
| Speed Grade | 20 MHz |
| RoHS Status | Non-compliant (legacy PQ package) |
PIC16C662-20/PQ 44-pin mqfp (pq) Pin Configuration Guide
Pin configuration for PIC16C662-20/PQ (44-pin mqfp (pq) package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for PIC16C662-20/PQ.
Refer to the datasheet for full pin configuration.
Typical Applications
PIC16C662-20/PQ is suitable for 6 applications: Industrial Control Panels, Appliance Control Boards, Switch-Mode Power Supply Secondary-Side Control, Automotive Body Electronics (Non-Safety), Sensor Hubs and Data Loggers, Uninterruptible Power Supply (UPS) Controllers.
Industrial Control Panels
The PIC16C662-20/PQ fits industrial control panels because its 33 I/O pins can directly drive relay coils, optocouplers, status LEDs, and keypads without external buffers, while the 7KB OTP memory holds deterministic ladder-logic-style firmware. The 20 MHz instruction rate (200 ns cycle) supports scan times under 10 ms for 100-point I/O panels. Its integrated USART links the panel to a PLC or HMI over RS-485, and the 8-channel 10-bit ADC reads analog sensors such as pressure transducers and thermistors in 4-20 mA loops. The 4.0-6.0 V supply range is well-matched to 5 V industrial rails, and the on-chip brown-out reset prevents false outputs during power dips that would otherwise latch a relay in the wrong state. Designers should add 100 nF ceramic decoupling at every VDD pin and a 10 uF bulk capacitor at the connector.
Recommended
Appliance Control Boards
The PIC16C662-20/PQ is well suited to white-goods and small-appliance control boards such as washing machines, dishwashers, microwave ovens, and HVAC damper actuators. The 10-bit ADC with 8 channels measures NTC temperature sensors, water level probes, and motor current via shunt resistors, while the 16-bit CCP module generates PWM outputs to drive TRIAC gates, brushless DC fans, or solenoid valves. With 7KB of OTP program memory, mature production firmware can be locked at the factory with no risk of accidental erasure in the field. The 33 I/O count directly supports multiplexed 7-segment displays, capacitive touch pads, and rotary encoder inputs. Brown-out reset and watchdog timer together survive the brown-outs and EMI bursts typical of motor-driven appliances.
Recommended
Switch-Mode Power Supply Secondary-Side Control
In isolated switch-mode power supplies the PIC16C662-20/PQ can implement the secondary-side controller for synchronous rectification, constant-current/constant-voltage (CC/CV) regulation, and PMBus-compatible telemetry. The 20 MHz instruction rate (5 MIPS) easily supports 100 kHz PWM update loops and digital filtering of the output voltage sense amplifier. The 10-bit ADC provides adequate resolution for the output voltage and current feedback, while the 7KB OTP memory holds lookup tables for temperature-compensated current setpoints. The USART provides the PMBus/I2C-style interface to a primary-side controller. The 4.0-6.0 V supply is conveniently derived from an auxiliary winding on the main transformer, eliminating the need for a separate bias supply.
Recommended
Automotive Body Electronics (Non-Safety)
The PIC16C662-20/PQ is used in non-safety automotive body-electronics modules such as interior lighting controllers, seat-position memories, mirror-adjustment modules, and aftermarket alarm systems. Its 33 I/O count easily drives multiple LED strings, H-bridges, and switch-matrix keypads, while the 10-bit ADC reads photodiodes, potentiometers, and current-sense shunts. The USART interfaces with the body control module over LIN or K-Line protocols when paired with a transceiver. The industrial-grade PIC16C662-04I/P variant extends the temperature range to -40 C to +85 C, and the flash-based PIC16F662 is the recommended migration for under-hood and AEC-Q100 applications. The on-chip watchdog timer catches software lockups caused by alternator-load-dump transients.
Recommended
Sensor Hubs and Data Loggers
The PIC16C662-20/PQ is a good fit for low-cost multi-channel sensor hubs that aggregate analog and digital sensor data and forward it over a serial link. The 8-channel 10-bit ADC scans thermistor, photodiode, and strain-gauge arrays with conversion times around 20 us per channel, and the 176-byte RAM buffers several samples between USART transmissions. The CCP module provides accurate time-stamping from a 16-bit timer, while the 7KB OTP memory holds calibration constants and linearization lookup tables. The 20 MHz instruction rate easily keeps pace with a 9600 or 19200 baud host link. A 32.768 kHz external watch crystal can drive Timer1 for RTC timekeeping, allowing the hub to log data with wall-clock timestamps even in sleep.
Recommended
Uninterruptible Power Supply (UPS) Controllers
The PIC16C662-20/PQ can implement the digital control heart of small-to-medium UPS systems, monitoring battery voltage, charge current, load current, and temperature while driving transfer relays and status displays. The 10-bit ADC continuously digitizes the battery sense amplifier, while the 33 I/O lines drive green/yellow/red status LEDs, audible alarms, and relay coils. The USART links the UPS to a host computer or RS-232 console for shutdown signaling, and the CCP module generates a precision 50/60 Hz reference for the inverter stage. Brown-out reset protects against half-charged battery firmware corruption, and the watchdog timer survives the heavy EMI of inverter switching. The 4.0-6.0 V supply is derived from the battery stack via a small linear regulator.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C662-20/PQ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C662-10E/L | PIC16C662-10/P | PIC16C662-04I/P | PIC16C65B-04I/PQ | PIC16C65B-04E/PQ | PIC16C64A-20/PQ |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin MQFP (PQ) | 44-pin ceramic DIP (L), same family | 44-pin plastic DIP (P), same family | 44-pin plastic DIP (P), same family | 44-pin MQFP (PQ) - same | 44-pin MQFP (PQ) - same | 44-pin MQFP (PQ) - same |
| Core | 8-bit PIC16 mid-range | 8-bit PIC16 mid-range | 8-bit PIC16 mid-range | 8-bit PIC16 mid-range | 8-bit PIC16 mid-range | 8-bit PIC16 mid-range | 8-bit PIC16 mid-range |
| Program Memory | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP |
| Maximum Clock Frequency | 20 MHz | 10 MHz | 10 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz |
| Number of I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 | 33 |
| ADC | 10-bit, 8 channels | 10-bit, 8 channels | 10-bit, 8 channels | 10-bit, 8 channels | 10-bit, 8 channels | 10-bit, 8 channels | 10-bit, 8 channels |
| Operating Temperature | 0 C to +70 C (commercial) | -40 C to +85 C (extended) | 0 C to +70 C (commercial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | -40 C to +125 C (extended) | 0 C to +70 C (commercial) |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | NRND | NRND |
Key Differentiators
- 20 MHz commercial-temperature speed grade (vs PIC16C662-04I/P)
- Same-family 44-MQFP pin-compatible flash migration path (vs PIC16C65B-04I/PQ)
- Full USART and 16-bit CCP integrated (vs PIC16C64A-20/PQ)
Design Notes
Estimated: at 20 MHz clock the PIC16C662-20/PQ draws approximately 15-20 mA from a 5 V supply, dominated by the oscillator and digital core. Place a 100 nF ceramic decoupling capacitor within 5 mm of every VDD/VSS pin pair and add a single 10 uF bulk aluminum-polymer or tantalum capacitor at the board power input. The on-chip brown-out reset (BOR) should be enabled in the configuration bits to prevent code execution from corrupted memory when VDD droops below approximately 4.0 V during motor inrush events.
Route the 20 MHz crystal traces (OSC1/OSC2) as short, symmetrical differential pair-like paths and guard them with a ground pour on both sides. Keep digital switching traces at least 5 mm away from the analog AVdd/AVss pins and the 10-bit ADC input traces to preserve 1 LSB accuracy. Place the MCLR pull-up resistor within 25 mm of the MCLR pin to provide a clean reset edge, and add a 100 nF cap to ground to filter ESD transients on the reset line.
OTP memory is one-time-programmable and cannot be erased, so every blank part discarded by a code bug is a real cost. Mitigate this by validating firmware on a flash-based PIC16F662 development board before committing to OTP production. Watchdog timer (WDT) must be explicitly disabled in the configuration bits if it is not used, otherwise a spurious WDT timeout in a long delay-loop will reset the application. Config bits must be set explicitly, because unprogrammed OTP cells read as '1' and many defaults are not suitable for production.
Compliance Information
Legacy PQ (Metric Quad Flat Pack) package is not lead-free / RoHS compliant; this is typical of PIC16C6x OTP parts shipped before 2006. AEC-Q100 qualification is not available for this part; the industrial-grade PIC16C662-04I/P variant is the closest alternative for -40 C to +85 C operation, while AEC-Q100 is achieved only on selected PIC16F / dsPIC families.
