PIC16C662T-20I/PT - 8-Bit OTP MCU, 7KB, 20MHz, 44-TQFP
MPN: PIC16C662T-20I/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.95 | $7.95 |
| 10 | $7.2 | $72.00 |
| 100 | $6.45 | $645.00 |
| 500 | $5.8 | $2,900.00 |
| 1,000 | $5.2 | $5,200.00 |
PIC16C662T-20I/PT Overview
What is a PIC 16C microcontroller? The PIC 16C series is Microchip's classic OTP-ROM 8-bit RISC microcontroller family based on a Harvard architecture with separate program and data buses, typically featuring a 14-bit instruction word, single-cycle instruction execution, on-chip peripherals (timers, ADC, USART, PWM), and ultra-low-power CMOS operation. Within the broader microcontroller taxonomy, the PIC 16C sits under 8-bit MCU -> microcontroller -> embedded controller -> semiconductor device, and historically preceded the flash-based PIC 16F family which is now the dominant mid-range Microchip MCU platform.
Key features include a 20MHz maximum clock (200ns instruction cycle), 33 bidirectional I/O pins, an 8-channel 8-bit A/D converter, two 8-bit timers and one 16-bit timer/counter, a watchdog timer with on-chip RC oscillator, and low-power Sleep mode. The device operates across the industrial -40C to +85C temperature range and supports in-circuit serial programming via Microchip's ICSP protocol even though the program memory itself is OTP. The 44-TQFP package exposes all peripheral pins on a compact 10x10mm footprint suitable for space-constrained industrial PCBs.
Architecturally, the PIC16C662 uses a RISC core with 35 single-word instructions, a hardware multiplier, and a 14-bit program word width. OTP memory provides one-time field programmability - it is cheaper than windowed EPROM and offers faster access than external EEPROM, but code cannot be erased or rewritten. The 20MHz clock yields 5 MIPS (million instructions per second) throughput, sufficient for motor control, sensor interfacing, and human-machine interface (HMI) panels.
Typical applications include industrial control panels, HVAC thermostat controllers, appliance user interfaces, motor-driver front-end controllers, security alarm panels, and small-form-factor sensor hubs. Engineers select this OTP part when unit costs matter and firmware is finalized before production, since OTP ROM is significantly cheaper per bit than flash at high volumes.
When designing with this part, note that OTP memory cannot be re-flashed; final firmware must be masked-ordered or field-OTP-programmed before PCB assembly. Plan the ICSP programming fixture and verification steps early. For prototypes and low-volume production, consider migrating to the PIC16F662 flash-based equivalent to allow iterative firmware updates.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, with all data validated as of 2026-09-18.
Drop-in alternatives for PIC16C662T-20I/PT — 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 PIC16C662T-20I/PT (same form factor and footprint) — differing in Package, Program Memory Size, Program Memory Type, Mounting Type, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C662T-20E/PT
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
PIC16C662-20I/P
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$5.45 / Unit
View Datasheet →PIC16F662-I/PT
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
PIC16C662-04I/PT
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
PIC16C662T-20I/PT Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology |
| Series | PIC 16C |
| Core Processor | PIC |
| Core Size | 8-Bit |
| Program Memory Size | 7KB (4K x 14) OTP |
| RAM Size | 176 bytes |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle | 200 ns (5 MIPS) |
| Supply Voltage (Vcc/Vdd) | 4 V to 6 V |
| Number of I/O Pins | 33 |
| A/D Converter | 8-bit, 8 channels |
| Timers | 2 x 8-bit + 1 x 16-bit |
| Package | 44-TQFP (10 x 10 mm) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (Industrial) |
| Program Memory Type | OTP (One-Time Programmable) |
| RoHS Status | RoHS3 Compliant |
| Lead Free | Yes |
PIC16C662T-20I/PT Pin Configuration
| Pin 1 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 2 | OSC2/CLKOUT — Oscillator output / clock output |
| Pin 3 | MCLR/VPP — Master clear reset / programming voltage input |
| Pin 4 | RA0/AN0 — Port A bit 0 / analog input 0 |
| Pin 5 | RA1/AN1 — Port A bit 1 / analog input 1 |
| Pin 6 | RA2/AN2 — Port A bit 2 / analog input 2 |
| Pin 7 | RA3/AN3/VREF — Port A bit 3 / analog input 3 / ADC voltage reference |
| Pin 8 | RA4/T0CKI — Port A bit 4 / Timer 0 clock input |
| Pin 9 | RA5/AN4/SS — Port A bit 5 / analog input 4 / SPI slave select |
| Pin 10 | VSS — Ground reference |
| Pin 11 | VDD — Positive supply voltage (4V to 6V) |
| Pin 12 | RB0/INT — Port B bit 0 / external interrupt input |
| Pin 13 | RB1 — Port B bit 1 |
| Pin 14 | RB2 — Port B bit 2 |
| Pin 15 | RB3 — Port B bit 3 |
| Pin 16 | RB4 — Port B bit 4 |
| Pin 17 | RB5 — Port B bit 5 |
| Pin 18 | RB6/PGC — Port B bit 6 / ICSP clock |
| Pin 19 | RB7/PGD — Port B bit 7 / ICSP data |
| Pin 20 | VSS — Ground reference |
| Pin 21 | VDD — Positive supply voltage (4V to 6V) |
| Pin 22 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer 1 oscillator output / clock input |
| Pin 23 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer 1 oscillator input / CCP2 output |
| Pin 24 | RC2/CCP1 — Port C bit 2 / CCP1 PWM/capture/compare output |
| Pin 25 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 26 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 27 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 28 | RC6/TX/CK — Port C bit 6 / USART TX / clock |
| Pin 29 | RC7/RX/DT — Port C bit 7 / USART RX / data |
| Pin 30 | VSS — Ground reference |
| Pin 31 | VDD — Positive supply voltage (4V to 6V) |
| Pin 32 | RD0 — Port D bit 0 |
| Pin 33 | RD1 — Port D bit 1 |
| Pin 34 | RD2 — Port D bit 2 |
| Pin 35 | RD3 — Port D bit 3 |
| Pin 36 | RD4 — Port D bit 4 |
| Pin 37 | RD5 — Port D bit 5 |
| Pin 38 | RD6 — Port D bit 6 |
| Pin 39 | RD7 — Port D bit 7 |
| Pin 40 | VSS — Ground reference |
| Pin 41 | VDD — Positive supply voltage (4V to 6V) |
| Pin 42 | RE0/RD — Port E bit 0 / parallel slave port read |
| Pin 43 | RE1/WR — Port E bit 1 / parallel slave port write |
| Pin 44 | RE2/CS — Port E bit 2 / parallel slave port chip select |
Typical Applications
PIC16C662T-20I/PT is suitable for 6 applications: Industrial Control Panels, HVAC Thermostat Controllers, Appliance User Interfaces, Motor-Driver Front-End Controllers, Security Alarm Panels, Sensor Hub Modules.
Industrial Control Panels
The PIC16C662T-20I/PT suits industrial control panels where its 33 I/O pins can directly drive 7-segment displays, keypad matrices, status LEDs, and relay coils without external glue logic. Its 20MHz clock delivers 5 MIPS throughput, enough to scan keypads, debounce inputs, and refresh multiplexed displays in real time within tight scan loops. The 8-channel 8-bit ADC reads panel-mounted potentiometers and analog sensors (temperature, pressure, humidity) for setpoint control. The 4V to 6V supply tolerance aligns with legacy 5V industrial rails, and the OTP memory locks the final control firmware at production, eliminating field-reprogramming risk and reducing unit cost. The -40C to +85C industrial temperature range covers most factory floor environments, and the 44-TQFP package provides a compact 10x10mm footprint suitable for tight panel enclosures.
Recommended
HVAC Thermostat Controllers
The PIC16C662T-20I/PT is well matched to HVAC thermostat designs where deterministic 5 MIPS processing drives PID temperature control loops and user interface handling simultaneously. Its on-chip 8-bit ADC samples thermistor or RTD sensors through 8 input channels, while the 16-bit timer/counter generates precise PWM outputs for triac-fired heater/coil stages. OTP memory is ideal here because HVAC firmware rarely changes after qualification, and the lower per-bit cost benefits consumer-volume production runs. The 176 bytes of RAM accommodate scheduling variables and EEPROM-emulated user settings with minimal external memory. The -40C to +85C industrial grade supports wall-mounted indoor installations and unconditioned mechanical rooms, and the 44-TQFP surface-mount package reflows cleanly on standard SMT lines, reducing assembly cost versus through-hole alternatives.
Recommended
Appliance User Interfaces
The PIC16C662T-20I/PT powers appliance user interfaces in washing machines, dishwashers, ovens, and microwave ovens where fixed-feature firmware and high-volume cost-down are top priorities. Its 33 I/O pins drive multi-digit 7-segment or dot-matrix displays, capacitive touch buttons via the ADC channels, and buzzer/relay outputs without external I/O expanders. The 20MHz instruction rate smoothly handles multi-task scheduling between UI refresh, sensor polling, and safety interlocks. OTP memory locks the final appliance program at production to prevent field tampering or accidental firmware corruption. The 4V to 6V supply operates directly from rectified 5V rails common in appliance power supplies, and the 44-TQFP package offers a robust surface-mount solution resistant to the vibration and humidity found in white goods. The -40C to +85C range covers kitchen and laundry environments.
Recommended
Motor-Driver Front-End Controllers
The PIC16C662T-20I/PT acts as the digital front-end controller for small BLDC, stepper, and brushed DC motor drivers in fans, pumps, and small appliances. Its 16-bit timer/counter generates the PWM channels required for variable-speed motor control, while the 8-bit ADC reads motor current via shunt amplifiers for closed-loop torque or speed regulation. The 20MHz clock and 200ns instruction cycle allow sub-microsecond PWM edge control, critical for low-inductance high-RPM motors. With 33 I/O lines, the MCU simultaneously drives gate-driver signals, Hall-sensor inputs, fault comparators, and serial diagnostics. The OTP memory locks the motor-control algorithm at production, eliminating field-bricking risk in cost-sensitive consumer motor products. The 44-TQFP package provides a small footprint, and the -40C to +85C industrial range supports motor-mounted electronics with self-heating considerations.
Recommended
Security Alarm Panels
The PIC16C662T-20I/PT fits security alarm panels where its 33 I/O pins connect directly to multiple zone inputs (door/window sensors, PIR motion detectors, glass-break sensors) and output relays for sirens and dialers. The 8-channel 8-bit ADC monitors backup battery voltage, sensor reference levels, and tamper loops, while the 16-bit timer drives precise entry/exit delay timing and watchdog supervision. OTP memory secures the alarm logic against reverse engineering and prevents field modification of compliance-certified firmware. The 5 MIPS throughput handles simultaneous zone scanning, communication protocol framing, and event logging. The 4V to 6V supply range accommodates battery-backed 5V alarm rails, and the -40C to +85C industrial range covers indoor installation environments including unheated garages and warehouses.
Recommended
Sensor Hub Modules
The PIC16C662T-20I/PT is well suited to compact sensor hub modules aggregating multiple analog and digital sensors for IoT edge devices, building automation, and environmental monitoring. The 8-channel 8-bit ADC digitizes analog sensor outputs (temperature, humidity, light, gas) while the 33 I/O lines interface to I2C, SPI, and UART peripherals including external flash memory for data logging. The 20MHz clock supports real-time sensor fusion calculations at sub-millisecond rates for responsive control feedback. OTP memory locks the sensor processing firmware at production, eliminating the risk of malicious firmware tampering in field-deployed IoT endpoints. The 44-TQFP surface-mount package reflows onto compact sensor PCBs alongside wireless modules, and the -40C to +85C range supports both indoor and sheltered outdoor installations. The 5V supply range allows direct integration with industrial 5V sensor buses.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C662T-20I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C662T-20E/PT | PIC16C662-20I/P | PIC16F662-I/PT | PIC16C662-04I/PT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-TQFP (PT) | 44-TQFP (PT) - same | 44-TQFP (PT) - same | 44-TQFP (PT) - same | 44-TQFP (PT) - same |
| Program Memory | 7KB OTP | 7KB OTP | 7KB OTP | 7KB Flash | 7KB OTP |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 4 MHz |
| RAM Size | 176 bytes | 176 bytes | 176 bytes | 176 bytes | 176 bytes |
| I/O Pins | 33 | 33 | 33 | 33 | 33 |
| Temperature Range | -40C to +85C (Industrial) | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) |
| Program Memory Type | OTP (one-time) | OTP (one-time) | OTP (one-time) | Flash (re-writable) | OTP (one-time) |
| Supply Voltage | 4V to 6V | 4V to 6V | 4V to 6V | 2V to 5.5V | 4V to 6V |
Key Differentiators
- OTP memory offers the lowest per-unit cost for high-volume fixed-firmware products (vs PIC16F662-I/PT)
- Industrial -40C to +85C temperature range covers most indoor industrial environments (vs PIC16C662T-20E/PT)
- Wide 5V-native supply range integrates directly with legacy industrial 5V rails (vs PIC16F662-I/PT)
Design Notes
The PIC16C662T-20I/PT operates from a 4V to 6V supply, so a regulated 5V rail is the natural choice for industrial designs. Place a 100nF ceramic decoupling capacitor as close as possible to each VDD pin (the 44-TQFP has multiple VDD pins: 11, 21, 31, 41) and a single 10uF bulk capacitor near the MCU. For battery-backed applications, the VDD rise time must be less than the device's power-on reset specification - typically below 50ms - to guarantee a clean POR. Add a reverse-polarity protection diode if the supply can be mis-wired in the field, especially for security and appliance installations.
Route the 20MHz crystal traces (OSC1/OSC2) as short and symmetrical as possible, keeping them away from high-current switching nodes and digital output edges. For an external crystal, use a grounded guard ring around the oscillator area to minimize radiated EMI. The MCLR pin requires a 10kohm pull-up to VDD; in noisy industrial environments, add a 100nF capacitor from MCLR to VDD for improved noise immunity. ICSP pins RB6/PGC and RB7/PGD should be brought out to a header or test pad for in-circuit programming without removing the MCU from the board.
OTP memory cannot be re-flashed - any code bug discovered after programming requires replacing the MCU, which destroys the original code. Always validate firmware on a flash-based PIC16F662 prototype before committing the final code to OTP parts. The configuration bits (oscillator selection, watchdog enable, code protection, brown-out voltage) must be set correctly during programming; an incorrect CONFIG can brick the part until the configuration word is properly programmed. The ADC's VREF input requires a low-impedance source - add a buffer op-amp if the reference divider is high-impedance, or ADC accuracy will suffer.
The 44-TQFP package has a typical thermal resistance of around 50C/W junction-to-ambient in still air; at 25mA active current and 5V supply, the MCU dissipates roughly 125mW, giving a 6C junction rise above ambient - usually negligible. However, in enclosed appliances or motor-mounted designs where ambient can reach +70C, the junction can approach +76C, still within the +85C industrial limit. For extended-temperature (E suffix) applications above +85C ambient, derate by reducing clock frequency or by improving PCB copper pour area beneath the exposed pad.
Compliance Information
RoHS3 compliant per Heisener product listing 2026-09-18. REACH, halogen-free, and conflict-minerals declarations should be requested directly from Microchip for full EU compliance documentation. AEC-Q100 not applicable - this is a general-purpose industrial MCU without automotive qualification; contact Microchip for automotive-grade PIC16 variants.