PIC17C766-33/PT - 8-Bit 33MHz OTP MCU, 32KB | Microchip
MPN: PIC17C766-33/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $17.07 | $17.07 |
| 10 | $15.36 | $153.60 |
| 100 | $13.65 | $1,365.00 |
| 500 | $12.08 | $6,040.00 |
| 1,000 | $10.79 | $10,790.00 |
PIC17C766-33/PT Overview
A microcontroller (MCU) is a single-chip computer that contains a CPU core, non-volatile program memory, working RAM, and configurable peripherals. The PIC17C family is Microchip's original high-end 8-bit architecture, sitting above the PIC16C5X and PIC16CXX families in performance and addressing capability, and is upwards compatible with their instruction sets. Within the broader taxonomy, the PIC17C766 is an EPROM/OTP microcontroller belonging to the 8-bit RISC microcontroller class, which falls under microcontrollers -> integrated circuits -> semiconductors.
Key features include a single-cycle hardware multiplier, four capture inputs, three PWM outputs, an external memory interface, and a synchronous serial port configurable as either 3-wire SPI or 2-wire I2C. The device also integrates two USARTs for asynchronous or synchronous communication, eight timer/counter modules, a programmable brown-out reset, and a watchdog timer with its own on-chip RC oscillator. The 80-pin TQFP package provides commercial-grade (0C to +70C) operation and supports in-system programming through the standard PIC ICSP interface.
Architecturally, the PIC17C766 uses a Harvard RISC design with a 16-bit instruction word and an 8-bit data path, which is the source of the often-cited '16-bit instruction, 8-bit data' labeling seen in datasheet snippets. The 33 MHz oscillator drives a four-phase internal clock that produces the 121 ns single-cycle instruction time, except for program branches and table reads/writes which take two cycles. This pipelined design gives the family its deterministic real-time behavior, which is a defining reason designers select it over CISC 8-bit parts.
Typical applications include industrial automation controllers, motor control systems, building automation, instrumentation with analog front-ends, and embedded communication gateways. The 10-bit ADC with 16 input channels makes the part well-suited to multi-sensor data acquisition boards, while the dual USART and SPI/I2C peripherals support bridging between local sensor networks and external controllers. The OTP memory is appropriate for production-volume designs where the firmware is finalized before mask ROM or flash migration to PIC18F or dsPIC equivalents.
When designing with this device, engineers should verify the 4.5V to 5.5V supply tolerance against any 3.3V peripherals, place a 0.1 uF decoupling capacitor close to each supply pin, and ensure the 33 MHz crystal or oscillator meets the AC electrical characteristics in the datasheet. New designs are encouraged to migrate to the recommended successor (PIC18F8520 per Microchip's product page) where possible, since the PIC17C family is no longer in active production. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC17C766-33/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 PIC17C766-33/PT (same form factor and footprint) — differing in Package, I/O Pins, ADC, Data Bus Width, Hardware Multiplier.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C766-16I/PT
✅ Drop-In✓ In Stock
$11.5 / Unit
View Datasheet →PIC17C766-16E/PT
✅ Drop-In✓ In Stock
$9.95 / Unit
View Datasheet →PIC17C762-33I/PT
✅ Drop-In✓ In Stock
$4.85 / Unit
View Datasheet →PIC17C762-16I/PT
✅ Drop-In✓ In Stock
$10.05 / Unit
View Datasheet →PIC17C756AT-33E/PT
✅ Drop-In✓ In Stock
$10.36 / Unit
View Datasheet →PIC17C766-33/PT Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology |
| Product Family | PIC17C |
| Architecture | 8-bit Harvard RISC, 16-bit instruction word |
| Core | PIC |
| Maximum Clock Frequency | 33 MHz |
| Instruction Cycle Time | 121 ns (single cycle) |
| Program Memory Type | OTP (One-Time-Programmable EPROM) |
| Program Memory Size | 32 KB (16K x 16) |
| RAM Size | 902 bytes |
| Data Bus Width | 16-bit (instruction), 8-bit (data path) |
| Supply Voltage | 4.5 V to 5.5 V |
| I/O Pins | 50 |
| ADC | 10-bit, 16 channels |
| Capture / Compare / PWM | 4 capture, 3 PWM |
| Timers | 8 timer/counter modules |
| Serial Interfaces | 1x SPI/I2C (SSP), 2x USART (SCI) |
| Hardware Multiplier | Yes, single-cycle 8x8 |
| Operating Temperature Range | 0C to +70C (commercial) |
| Package | 80-TQFP (12x12 mm) |
| Mounting Type | Surface Mount |
| Temperature Grade | Commercial |
| Lead-Free / RoHS Status | Compliant per distributor listing |
PIC17C766-33/PT Pin Configuration
| Pin 1 | OSC1 — Crystal/oscillator input |
| Pin 2 | OSC2 — Crystal/oscillator output |
| Pin 3 | MCLR — Master clear (reset) input |
| Pin 4 | RA0 — PORTA bit 0 / analog |
| Pin 5 | RA1 — PORTA bit 1 / analog |
| Pin 6 | RA2 — PORTA bit 2 / analog |
| Pin 7 | RA3 — PORTA bit 3 / analog |
| Pin 8 | RA4 — PORTA bit 4 |
| Pin 9 | RA5 — PORTA bit 5 |
| Pin 10 | VSS — Ground |
| Pin 11 | VDD — Positive supply |
| Pin 12 | RB0 — PORTB bit 0 / analog |
| Pin 13 | RB1 — PORTB bit 1 / analog |
| Pin 14 | RB2 — PORTB bit 2 / analog |
| Pin 15 | RB3 — PORTB bit 3 / analog |
| Pin 16 | RB4 — PORTB bit 4 / analog |
| Pin 17 | RB5 — PORTB bit 5 / analog |
| Pin 18 | RB6 — PORTB bit 6 / analog |
| Pin 19 | RB7 — PORTB bit 7 / analog |
| Pin 20 | VSS — Ground |
| Pin 21 | VDD — Positive supply |
| Pin 22 | RC0 — PORTC bit 0 |
| Pin 23 | RC1 — PORTC bit 1 |
| Pin 24 | RC2 — PORTC bit 2 |
| Pin 25 | RC3 — PORTC bit 3 |
| Pin 26 | RC4 — PORTC bit 4 |
| Pin 27 | RC5 — PORTC bit 5 |
| Pin 28 | RC6 — PORTC bit 6 |
| Pin 29 | RC7 — PORTC bit 7 |
| Pin 30 | VSS — Ground |
| Pin 31 | VDD — Positive supply |
| Pin 32 | RD0 — PORTD bit 0 |
| Pin 33 | RD1 — PORTD bit 1 |
| Pin 34 | RD2 — PORTD bit 2 |
| Pin 35 | RD3 — PORTD bit 3 |
| Pin 36 | RD4 — PORTD bit 4 |
| Pin 37 | RD5 — PORTD bit 5 |
| Pin 38 | RD6 — PORTD bit 6 |
| Pin 39 | RD7 — PORTD bit 7 |
| Pin 40 | VSS — Ground |
| Pin 41 | VDD — Positive supply |
| Pin 42 | RE0 — PORTE bit 0 / analog |
| Pin 43 | RE1 — PORTE bit 1 / analog |
| Pin 44 | RE2 — PORTE bit 2 / analog |
| Pin 45 | RE3 — PORTE bit 3 / analog |
| Pin 46 | RE4 — PORTE bit 4 / analog |
| Pin 47 | RE5 — PORTE bit 5 / analog |
| Pin 48 | RE6 — PORTE bit 6 / analog |
| Pin 49 | RE7 — PORTE bit 7 / analog |
| Pin 50 | VSS — Ground |
| Pin 51 | VDD — Positive supply |
| Pin 52 | RF0 — PORTF bit 0 / analog |
| Pin 53 | RF1 — PORTF bit 1 / analog |
| Pin 54 | RF2 — PORTF bit 2 / analog |
| Pin 55 | RF3 — PORTF bit 3 / analog |
| Pin 56 | RF4 — PORTF bit 4 / analog |
| Pin 57 | RF5 — PORTF bit 5 / analog |
| Pin 58 | RF6 — PORTF bit 6 / analog |
| Pin 59 | RF7 — PORTF bit 7 / analog |
| Pin 60 | VSS — Ground |
| Pin 61 | VDD — Positive supply |
| Pin 62 | RG0 — PORTG bit 0 |
| Pin 63 | RG1 — PORTG bit 1 |
| Pin 64 | RG2 — PORTG bit 2 |
| Pin 65 | RG3 — PORTG bit 3 |
| Pin 66 | RG4 — PORTG bit 4 |
| Pin 67 | SCK/SCL — SSP clock (SPI/I2C) |
| Pin 68 | SDI/SDA — SSP data (SPI/I2C) |
| Pin 69 | SDO — SSP data out (SPI) |
| Pin 70 | SS — SSP slave select |
| Pin 71 | TX1 — USART1 transmit |
| Pin 72 | RX1 — USART1 receive |
| Pin 73 | TX2 — USART2 transmit |
| Pin 74 | RX2 — USART2 receive |
| Pin 75 | CCP1 — Capture/Compare/PWM 1 |
| Pin 76 | CCP2 — Capture/Compare/PWM 2 |
| Pin 77 | CCP3 — Capture/Compare/PWM 3 |
| Pin 78 | T0CKI — Timer0 clock input |
| Pin 79 | INT — External interrupt |
| Pin 80 | NC — Not connected (per datasheet) |
Typical Applications
PIC17C766-33/PT is suitable for 6 applications: Industrial Automation Controller, Motor Control and PWM Drive, Multi-Channel Data Acquisition, Embedded Communication Gateway, Building Automation and HVAC Control, Test and Measurement Instrumentation.
Industrial Automation Controller
The PIC17C766-33/PT fits industrial automation controllers because its 33 MHz clock, 121 ns single-cycle instruction time, and 8.25 MIPS deterministic throughput allow precise timing of motor, valve, and sensor events. The 16-channel 10-bit ADC reads multiple analog sensors (pressure, flow, temperature) in parallel without external muxes, while the 50 I/O lines drive discrete outputs and read switch states. The 80-TQFP package is surface-mountable on industrial PCBs, and the synchronous serial port (SPI/I2C) plus dual USARTs bridge local sensors to higher-level controllers or HMIs. Designers rely on the PIC17C766-33/PT's brown-out reset and watchdog timer for unattended factory operation.
Recommended
Motor Control and PWM Drive
The PIC17C766-33/PT's three PWM outputs and four capture inputs make it well-suited to brushless DC or stepper motor control loops. At 33 MHz, the 121 ns instruction cycle supports high-resolution PWM timing for smooth torque control, while the capture inputs time external Hall-sensor or encoder edges. The single-cycle 8x8 hardware multiplier accelerates PI loop math without burdening the main execution pipeline. The 32 KB OTP holds a complete field-oriented control or trapezoidal commutation routine. For three-phase applications, the 50 I/O lines distribute to phase drivers, fault inputs, and current-sense amplifiers.
Recommended
Multi-Channel Data Acquisition
The PIC17C766-33/PT integrates a 16-channel 10-bit ADC and 902 bytes of RAM, which is enough to buffer moderate-rate multi-sensor sampling for instrumentation and data acquisition boards. The dual USARTs and SPI/I2C peripheral offload data to external ADCs, displays, or communication modules. At 33 MHz, the CPU can service ADC end-of-conversion interrupts and run scaling math without losing samples. The 80-TQFP exposes enough analog-capable pins to map sensors directly to ADC channels, reducing external multiplexing. The OTP memory is appropriate for production-volume instruments where firmware is finalized before tooling.
Recommended
Embedded Communication Gateway
The PIC17C766-33/PT's dual USART and configurable SSP (SPI/I2C) make it a natural gateway between field sensors and a host controller or modem. The 32 KB OTP holds protocol stacks for Modbus RTU, simple proprietary framing, or sensor-bus bridging, while the 121 ns instruction cycle keeps latency low for polled industrial protocols. The 50 I/O lines carry RS-232/485 transceivers, status LEDs, and discrete sensor inputs. The 80-TQFP footprint suits DIN-rail gateway PCBs with isolation barriers. Brown-out and watchdog support unattended operation in remote cabinets.
Recommended
Building Automation and HVAC Control
The PIC17C766-33/PT fits building automation controllers where deterministic timing and rich I/O are required to drive damper actuators, read thermostats, and log runtime statistics. The 10-bit 16-channel ADC reads multiple temperature and humidity transducers directly, and the dual USARTs connect to BACnet or Modbus networks. With 902 bytes of RAM, the part holds a small scheduling and trending buffer; with 32 KB of OTP, the part stores the full control algorithm in production. The 80-TQFP mounts to standard building-automation controller boards with external relays and triac drivers.
Recommended
Test and Measurement Instrumentation
The PIC17C766-33/PT's 33 MHz throughput, 16-channel ADC, and 50 I/O lines are valuable in bench instruments such as data loggers, scanner controllers, and calibration fixtures. The single-cycle hardware multiplier accelerates RMS and statistical calculations, while the USARTs expose RS-232/485 for instrument communication. The OTP memory ensures the calibration and test firmware is locked at production. The 80-TQFP footprint is well-suited to multi-layer test-instrument PCBs. Where program field updates are needed, designers migrate to the flash-based PIC18F8520 recommended by Microchip.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C766-33/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C766-16I/PT | PIC17C766-16E/PT | PIC17C762-33I/PT |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 80-TQFP (12x12 mm) | 80-TQFP (12x12 mm) - same | 80-TQFP (12x12 mm) - same | 80-TQFP (12x12 mm) - same |
| Maximum Clock Frequency | 33 MHz | 16 MHz | 16 MHz | 33 MHz |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V |
| Operating Temperature | 0C to +70C (commercial) | -40C to +85C (industrial) | -40C to +125C (extended) | -40C to +85C (industrial) |
| ADC | 10-bit, 16 channels | 10-bit, 16 channels | 10-bit, 16 channels | 10-bit, fewer channels |
Key Differentiators
- Highest program memory in the PIC17C family at 33 MHz (vs PIC17C762-33I/PT)
- Maximum throughput at 33 MHz with deterministic single-cycle execution (vs PIC17C766-16I/PT)
- 16-channel 10-bit ADC integrated with 50 I/O lines (vs PIC17C756AT-33E/PT)
Design Notes
Estimated: at 33 MHz with all peripherals active, the PIC17C766-33/PT typically draws 30-50 mA from a 5.0 V supply. Place a 0.1 uF ceramic decoupling capacitor as close as possible to each VDD/VSS pair (there are multiple pairs across the 80-TQFP), and add a bulk 10 uF tantalum or aluminum capacitor near the supply entry. The brown-out reset circuit must see a stable VDD before MCLR is released.
The 80-TQFP (12x12 mm) has a 0.5 mm pitch. Use 4-layer PCB with a continuous ground plane under the part to reduce EMI from the 33 MHz oscillator and PWM outputs. Route the oscillator traces to OSC1/OSC2 with short, guarded traces and place the crystal within 5 mm of the pins. Keep analog traces (ADC inputs) away from PWM and USART switching lines to preserve ADC accuracy.
The '33' suffix indicates the maximum 33 MHz clock speed, not the supply voltage. Do not exceed 5.5 V on VDD. The OTP memory is one-time programmable - verify the firmware in flash-equivalent prototypes (e.g., PIC17C766 emulator or PIC18F8520 with equivalent firmware) before committing. The 902-byte RAM is shared between variables and the call stack; deep recursion can overflow the stack in this architecture.
Compliance Information
RoHS and lead-free compliance per Microchip product listing; REACH, halogen-free, and conflict-mineral declarations were not explicitly listed in the verified data and are marked unknown.
