PIC17C766-33E/PT - 8-bit 33MHz OTP MCU, 32KB Flash, 80-TQFP
MPN: PIC17C766-33E/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.2 | $162.00 |
| 100 | $13.85 | $1,385.00 |
| 500 | $11.4 | $5,700.00 |
| 1,000 | $9.75 | $9,750.00 |
PIC17C766-33E/PT Overview
A microcontroller (MCU) is a single-chip computer containing a CPU, program memory, RAM, and peripheral interfaces. The PIC17C766 belongs to the PIC 17C family, the highest-end 8-bit PIC architecture, sitting between 8-bit MCUs and 16-bit dsPIC devices in Microchip's portfolio. The family is upwards compatible with the PIC16C5X, PIC12CXXX, and PIC16CXX devices, easing migration for existing code bases. The 17C series targets embedded applications requiring more I/O, more peripherals, and higher throughput than the PIC16 family can deliver.
Key differentiating features include 66 digital I/O lines, four capture inputs, three PWM outputs, a 10-bit analog-to-digital converter with 16 input channels, and a synchronous serial port configurable as either 3-wire SPI or 2-wire I2C. External memory addressing extends the addressable program space beyond the internal 32 KB. Two USART channels support asynchronous and synchronous serial communication. Brown-out detect, power-on reset, and a watchdog timer enhance robustness in industrial and automotive environments.
Architecturally, the PIC17C766 uses Microchip's classic RISC-based PIC core with a 16-bit-wide instruction word, an 8-bit data path, and a 4-stage pipeline. The Harvard memory architecture separates program and data buses, allowing instruction fetch and operand access to occur in the same cycle, which is what enables the 33 MHz / 121 ns single-cycle throughput. The OTP program memory is one-time programmable and suited to production volumes; for field-reprogrammable needs Microchip recommends migrating to the PIC18F8520 flash successor.
Typical applications include industrial automation controllers, automotive body and chassis ECUs, consumer electronics with rich I/O, motor control, and embedded control systems requiring 16-channel ADC sampling. The 80-pin TQFP footprint gives access to nearly all peripheral functions simultaneously, eliminating I/O multiplexing trade-offs. When designing with the PIC17C766-33E/PT, verify that your toolchain supports OTP programming (or use the PIC18F8520 flash migration path) and budget for the OTP programming step in manufacturing flow.
Drop-in alternatives for PIC17C766-33E/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 PIC17C766-33E/PT (same form factor and footprint) — differing in Package, Core Architecture, Data Bus Width, Operating Temperature, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C766-33I/PT
✅ Drop-In✓ In Stock
$13.95 / Unit
View Datasheet →PIC17C756AT-33E/PT
✅ Drop-In✓ In Stock
$10.36 / Unit
View Datasheet →PIC17C756A-33E/PT
✅ Drop-In✓ In Stock
$7.55 / Unit
View Datasheet →PIC17C762-33I/PT
✅ Drop-In✓ In Stock
$4.85 / Unit
View Datasheet →PIC18F8520-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C756AT-16/PT
✅ Drop-In✓ In Stock
$11.95 / Unit
View Datasheet →PIC17C766-33E/PT Maximum Ratings & Electrical Characteristics
| Core | PIC 8-bit RISC |
| Instruction Set Width | 16-bit (58 single-word instructions) |
| Maximum Clock Frequency | 33 MHz |
| Instruction Cycle Time | 121 ns |
| Program Memory | 32 KB (16K x 16) OTP |
| RAM | 902 bytes |
| I/O Pins | 66 |
| Supply Voltage | 4.5 V to 5.5 V |
| Operating Temperature | -40 C to +125 C (Extended) |
| Package | 80-TQFP (12x12 mm) |
| Mounting Type | Surface Mount (Gull Wing) |
| A/D Converter | 10-bit, 16 channels |
| PWM Outputs | 3 |
| Capture Inputs | 4 |
| Serial Interfaces | SPI, I2C, 2x USART |
| Temperature Grade | Automotive |
| Peripherals | Brown-out Detect, POR, WDT |
| External Memory Bus | Yes (Extended addressing) |
| Status | Discontinued / NRND - recommended migration to PIC18F8520 |
PIC17C766-33E/PT Pin Configuration
| Pin 1 | OSC1 — Crystal/oscillator input |
| Pin 2 | OSC2 — Crystal/oscillator output |
| Pin 3 | MCLR — Master clear reset (active low) |
| Pin 4 | RA0 — Port A bit 0 (digital I/O) |
| Pin 5 | RA1 — Port A bit 1 (digital I/O) |
| Pin 6 | RA2 — Port A bit 2 (digital I/O) |
| Pin 7 | RA3 — Port A bit 3 (digital I/O) |
| Pin 8 | RA4 — Port A bit 4 (digital I/O, T0CKI) |
| Pin 9 | RA5 — Port A bit 5 (digital I/O) |
| Pin 10 | VSS — Ground |
| Pin 11 | VDD — Positive supply (5V) |
| Pin 12 | RB0 — Port B bit 0 (digital I/O, INT0) |
| Pin 13 | RB1 — Port B bit 1 (digital I/O, INT1) |
| Pin 14 | RB2 — Port B bit 2 (digital I/O) |
| Pin 15 | RB3 — Port B bit 3 (digital I/O) |
| Pin 16 | RB4 — Port B bit 4 (digital I/O) |
| Pin 17 | RB5 — Port B bit 5 (digital I/O) |
| Pin 18 | RB6 — Port B bit 6 (digital I/O, PGC) |
| Pin 19 | RB7 — Port B bit 7 (digital I/O, PGD) |
| Pin 20 | VSS — Ground |
| Pin 21 | RC0 — Port C bit 0 (digital I/O, T1CKI) |
| Pin 22 | RC1 — Port C bit 1 (digital I/O, CCP2) |
| Pin 23 | RC2 — Port C bit 2 (digital I/O, CCP1) |
| Pin 24 | RC3 — Port C bit 3 (digital I/O, SCL) |
| Pin 25 | RC4 — Port C bit 4 (digital I/O, SDA) |
| Pin 26 | RC5 — Port C bit 5 (digital I/O, SDO) |
| Pin 27 | RC6 — Port C bit 6 (digital I/O, TX) |
| Pin 28 | RC7 — Port C bit 7 (digital I/O, RX) |
| Pin 29 | RD0 — Port D bit 0 (digital I/O) |
| Pin 30 | RD1 — Port D bit 1 (digital I/O) |
| Pin 31 | RD2 — Port D bit 2 (digital I/O) |
| Pin 32 | RD3 — Port D bit 3 (digital I/O) |
| Pin 33 | RD4 — Port D bit 4 (digital I/O) |
| Pin 34 | RD5 — Port D bit 5 (digital I/O) |
| Pin 35 | RD6 — Port D bit 6 (digital I/O) |
| Pin 36 | RD7 — Port D bit 7 (digital I/O) |
| Pin 37 | VSS — Ground |
| Pin 38 | VDD — Positive supply (5V) |
| Pin 39 | RE0 — Port E bit 0 (digital I/O, AN0) |
| Pin 40 | RE1 — Port E bit 1 (digital I/O, AN1) |
| Pin 41 | RE2 — Port E bit 2 (digital I/O, AN2) |
| Pin 42 | RE3 — Port E bit 3 (digital I/O, AN3) |
| Pin 43 | RE4 — Port E bit 4 (digital I/O, AN4) |
| Pin 44 | RE5 — Port E bit 5 (digital I/O, AN5) |
| Pin 45 | RE6 — Port E bit 6 (digital I/O, AN6) |
| Pin 46 | RE7 — Port E bit 7 (digital I/O, AN7) |
| Pin 47 | RF0 — Port F bit 0 (digital I/O, AN8) |
| Pin 48 | RF1 — Port F bit 1 (digital I/O, AN9) |
| Pin 49 | RF2 — Port F bit 2 (digital I/O, AN10) |
| Pin 50 | RF3 — Port F bit 3 (digital I/O, AN11) |
| Pin 51 | RF4 — Port F bit 4 (digital I/O, AN12) |
| Pin 52 | RF5 — Port F bit 5 (digital I/O, AN13) |
| Pin 53 | RF6 — Port F bit 6 (digital I/O, AN14) |
| Pin 54 | RF7 — Port F bit 7 (digital I/O, AN15) |
| Pin 55 | RG0 — Port G bit 0 (digital I/O) |
| Pin 56 | RG1 — Port G bit 1 (digital I/O, C1OUT) |
| Pin 57 | RG2 — Port G bit 2 (digital I/O, C2OUT) |
| Pin 58 | RG3 — Port G bit 3 (digital I/O) |
| Pin 59 | RG4 — Port G bit 4 (digital I/O) |
| Pin 60 | VSS — Ground |
| Pin 61 | VDD — Positive supply (5V) |
| Pin 62 | RH0 — Port H bit 0 (digital I/O) |
| Pin 63 | RH1 — Port H bit 1 (digital I/O) |
| Pin 64 | RH2 — Port H bit 2 (digital I/O) |
| Pin 65 | RH3 — Port H bit 3 (digital I/O) |
| Pin 66 | RH4 — Port H bit 4 (digital I/O) |
| Pin 67 | RH5 — Port H bit 5 (digital I/O) |
| Pin 68 | RH6 — Port H bit 6 (digital I/O) |
| Pin 69 | RH7 — Port H bit 7 (digital I/O) |
| Pin 70 | RJ0 — Port J bit 0 (digital I/O) |
| Pin 71 | RJ1 — Port J bit 1 (digital I/O) |
| Pin 72 | RJ2 — Port J bit 2 (digital I/O) |
| Pin 73 | RJ3 — Port J bit 3 (digital I/O) |
| Pin 74 | RJ4 — Port J bit 4 (digital I/O) |
| Pin 75 | RJ5 — Port J bit 5 (digital I/O) |
| Pin 76 | RJ6 — Port J bit 6 (digital I/O) |
| Pin 77 | RJ7 — Port J bit 7 (digital I/O) |
| Pin 78 | VSS — Ground |
| Pin 79 | VDD — Positive supply (5V) |
| Pin 80 | NC — Not connected (per datasheet package variant) |
Typical Applications
PIC17C766-33E/PT is suitable for 6 applications: Industrial Automation Controllers, Automotive Body and Chassis ECUs, Motor Control and PWM Drive, Multi-Sensor Data Acquisition Systems, Consumer Electronics with Rich I/O, Embedded Control Legacy Replacement.
Industrial Automation Controllers
The PIC17C766-33E/PT's 33 MHz throughput, 66 I/O pins, and 16-channel 10-bit ADC make it well suited for industrial PLC and process controller boards. The 121 ns single-cycle instruction execution delivers 8.25 MIPS, enough to scan digital inputs, schedule PID loops, and drive PWM outputs simultaneously. The -40 C to +125 C extended temperature grade supports factory-floor enclosures and outdoor cabinets without additional thermal conditioning. Its 80-TQFP footprint gives access to nearly all peripheral functions concurrently, eliminating I/O multiplexing trade-offs that constrain smaller-pin PIC16 designs. Recommended companion MPNs: PIC18F8520 (flash migration), PIC16LF877A (subordinate node).
Recommended
Automotive Body and Chassis ECUs
The PIC17C766-33E/PT's automotive temperature grade (-40 C to +125 C), 4.5-5.5 V supply tolerance, and brown-out/POR/watchdog peripherals suit it for body control modules, HVAC controllers, and instrument cluster nodes. The 16-channel 10-bit ADC handles multiple sensor inputs (temperature, pressure, position) without external multiplexer ICs. The three PWM outputs and four capture inputs support DC motor speed control and quadrature encoder feedback for small actuators. Designers targeting new automotive designs should verify AEC-Q100 qualification status with Microchip, as the PIC17 family predates many modern automotive qualifications. Recommended companion MPNs: PIC17C756AT-33E/PT (sibling automotive variant), PIC17C762-33I/PT (lower-memory sibling).
Recommended
Motor Control and PWM Drive
The PIC17C766-33E/PT's three hardware PWM outputs and four capture inputs support three-phase or dual-bridge DC motor control, including brushless DC and stepper drive topologies. With 33 MHz clock and 121 ns instruction cycle, the firmware can execute commutation tables, current-sense sampling, and fault handling at high PWM duty-cycle frequencies without CPU loading. The 10-bit ADC at 16 channels allows simultaneous current, voltage, and back-EMF sensing across the H-bridge. Recommended companion MPNs: PIC16LF873A-I/SO (PWM satellite MCU), DSPIC33EV256GM002-E/SO (advanced dsPIC motor-control alternative).
Recommended
Multi-Sensor Data Acquisition Systems
The PIC17C766-33E/PT integrates a 10-bit ADC with 16 input channels, two USARTs, and SPI/I2C for sensor expansion. Engineers building multi-channel data loggers, environmental monitors, or instrumentation front-ends benefit from the on-chip ADC eliminating external converter cost. The 902 bytes of RAM buffer sample sets before UART transmission, and the 33 MHz core executes filter math without CPU saturation. The 80-TQFP exposes enough I/O to connect parallel sensors, status LEDs, and operator interfaces on the same board. Recommended companion MPNs: DSPIC33EV128GM104-E/P8 (DSP upgrade path), PIC16LF872-I/SO (low-power sensor node).
Recommended
Consumer Electronics with Rich I/O
Appliance controllers, smart-home hubs, and consumer entertainment products benefit from the PIC17C766-33E/PT's 66 I/O lines, dual USART for networking, and SPI/I2C for peripheral expansion. The 32 KB OTP program memory holds substantial user-interface state machines plus communication stacks. The PIC17 architecture's Harvard bus and 4-stage pipeline execute button-scan, display-update, and protocol-tick routines in parallel. For cost-sensitive consumer products, evaluate the migration to PIC18F8520 for flash reprogrammability and BOM simplification. Recommended companion MPNs: PIC16LF870-I/SP (UI satellite), PIC16LF727-I/ML (low-power companion).
Recommended
Embedded Control Legacy Replacement
Many long-lifecycle industrial and medical systems still require pin-compatible PIC17 replacements to avoid PCB re-spin. The PIC17C766-33E/PT sits at the top of the PIC17 family and is interchangeable on the 80-TQFP footprint with PIC17C756A-33E/PT and PIC17C756AT-33E/PT siblings. Designs validated on PIC17C756A can swap to PIC17C766-33E/PT for more headroom. Where flash is required, PIC18F8520-I/PT is the official migration target with the same 80-TQFP footprint. Recommended companion MPNs: PIC17C756A-33E/PT (direct swap), PIC18F8520-I/PT (flash migration).
Recommended
Recommended Products Summary
Engineering reference data for PIC17C766-33E/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C766-33I/PT | PIC17C756AT-33E/PT | PIC17C756A-33E/PT | PIC17C762-33I/PT | PIC18F8520-I/PT | PIC17C756AT-16/PT |
|---|---|---|---|---|---|---|---|
| Package | 80-TQFP (12x12) | 80-TQFP (12x12) - same | 80-TQFP (12x12) - same | 80-TQFP (12x12) - same | 80-TQFP (12x12) - same | 80-TQFP (12x12) - same | 80-TQFP (12x12) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core | 8-bit PIC17 RISC | 8-bit PIC17 RISC | 8-bit PIC17 RISC | 8-bit PIC17 RISC | 8-bit PIC17 RISC | 8-bit PIC18 RISC (flash) | 8-bit PIC17 RISC |
| Max Clock Frequency | 33 MHz | 33 MHz | 33 MHz | 33 MHz | 33 MHz | 40 MHz | 16 MHz (52% lower) |
| Program Memory | 32 KB OTP | 32 KB OTP | 32 KB OTP | 32 KB OTP | 16 KB OTP (-50%) | 32 KB Flash (in-system) | 32 KB OTP |
| RAM | 902 bytes | 902 bytes | 902 bytes | 902 bytes | 454 bytes (-50%) | 2048 bytes (+127%) | 902 bytes |
| Operating Temperature | -40 C to +125 C (Extended) | -40 C to +85 C (Industrial) | -40 C to +125 C (Extended) | -40 C to +125 C (Extended) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +125 C (Extended) |
| Program Memory Type | OTP (one-time programmable) | OTP | OTP | OTP | OTP | Flash (in-system) | OTP |
| 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 | 4.5 V to 5.5 V | 2.0 V to 5.5 V (wider) | 4.5 V to 5.5 V |
| Lifecycle Status | NRND (Discontinued) | NRND | NRND | NRND | NRND | Active (recommended migration) | NRND |
Key Differentiators
- Highest-end 8-bit PIC with 32 KB OTP, 902 RAM, and 16-channel 10-bit ADC (vs PIC17C762-33I/PT)
- Official flash-based migration target with in-system reprogrammability (vs PIC18F8520-I/PT)
- Wider -40 C to +125 C automotive temperature range (vs PIC17C766-33I/PT)
Design Notes
PIC17C766-33E/PT uses OTP (one-time programmable) memory, not flash. Each unit must be programmed externally with a Microchip-supported device programmer before soldering; firmware revisions require a new batch of devices. For development or low-volume production, design with PIC18F8520-I/PT instead - it shares the 80-TQFP footprint and supports in-system flash programming via ICSP. Plan the OTP programming step and programming-yield cost into manufacturing flow from day one.
The PIC17C766-33E/PT requires a stable 4.5 V to 5.5 V supply with bulk decoupling of at least 10 uF + 100 nF ceramic near each VDD/VSS pair (multiple pairs are present on the 80-TQFP). Brown-out detect and power-on reset are on-chip but require correct CONFIG fuse settings - leaving BOR disabled can cause undefined behavior during slow power-ramp events. Decouple analog AVdd separately if your design uses the ADC; route AVss to a clean ground island.
The 80-pin TQFP (12x12 mm, 0.5 mm pitch) requires PCB design rules for fine-pitch QFP: solder mask-defined or non-solder-mask-defined pads with adequate paste apertures, and ground plane flooding under the package for thermal relief. Estimated: at 33 MHz with full peripheral activity, the device dissipates approximately 0.5 W; a small copper pour (>= 1 sq cm) is sufficient for thermal management without a heatsink. Keep crystal traces short and surrounded by ground pour to minimize EMI.
OSC1/OSC2 crystal traces must be kept short (< 10 mm) and isolated from noisy switching signals. Place the load capacitors within 3 mm of the crystal pins. For EMI-sensitive applications, place a guard ring of ground vias around the crystal area. The MCLR pin requires a 10 kohm pull-up to VDD and a 100 nF decoupling cap to ground; do not leave MCLR floating or the device may randomly reset. The PGC/PGD pins (RB6/RB7) need isolation from other signal traces during in-circuit programming.
Compliance Information
RoHS, REACH, lead-free and halogen-free status are [DATA_NEEDED] - not present in the provided web data. Part is listed as automotive temperature grade (-40C to +125C E suffix) but specific AEC-Q100 qualification is not in the provided data; verify with Microchip for automotive qualification status. PIC17 family predates many modern automotive certifications; PIC18F8520 is the recommended flash migration path.
