PIC17C756AT-33E/L - 8-Bit 33MHz OTP MCU 32KB | 68-PLCC
MPN: PIC17C756AT-33E/L ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.2 | $162.00 |
| 100 | $13.85 | $1,385.00 |
| 500 | $11.9 | $5,950.00 |
| 1,000 | $10.4 | $10,400.00 |
PIC17C756AT-33E/L Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (ROM/Flash/OTP), data memory (RAM), and programmable I/O peripherals. The 8-bit PIC17C architecture sits at the top of Microchip's original 8-bit hierarchy (PIC16 -> PIC17 -> PIC18), offering expanded peripherals, linear memory addressing, and faster execution than the popular PIC16 family, while predating the flash-based PIC18F successors.
Key features include 50 digital I/O pins, an internal 8-bit data bus with 16-bit instruction path, 8 MIPS sustained throughput, an analog comparator module, capture/compare/PWM, USART, and an 8-channel 10-bit ADC. The OTP program memory allows factory or volume one-time programming for production runs, making this part well suited for mature industrial designs. Only 58 single-word instructions need to be learned, simplifying firmware development.
Typical applications include industrial automation controllers, automotive body and chassis electronics, consumer appliances with keypad/display interfaces, and embedded control of legacy PIC-based systems. The wide 4.5 V to 5.5 V supply range and 50 I/O channels make it suitable for motor control front-ends, sensor aggregation nodes, and human-machine interface (HMI) boards. Its 33 MHz throughput comfortably handles real-time control loops, UART bridging, and PWM-driven actuators.
When designing with this part, ensure the OTP programming step is factored into production logistics and that adequate decoupling (100 nF + 10 µF) is placed close to VDD pins. Designers migrating to a flash-based equivalent should evaluate Microchip's recommended successor (PIC18F6520) since PIC17C parts are not recommended for new designs.
Drop-in alternatives for PIC17C756AT-33E/L — 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 PIC17C756AT-33E/L (same form factor and footprint) — differing in Package, Mounting Type, ADC, Core Architecture, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C756AT-33/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C756AT-33I/L
✅ Drop-In✓ In Stock
$12.4 / Unit
View Datasheet →PIC17C756A-33I/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C756AT-16/L
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$13.2 / Unit
View Datasheet →PIC17C752T-33/L
✅ Drop-In✓ In Stock
$14.2 / Unit
View Datasheet →PIC17C756A-33E/L
✅ Drop-In✓ In Stock
$9.4 / Unit
View Datasheet →PIC17C756AT-33E/L Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC |
| Family | PIC17C |
| CPU Width | 8-bit data / 16-bit instruction |
| Maximum Clock Frequency | 33 MHz |
| Instruction Throughput | 8.25 MIPS (121 ns per instruction) |
| Program Memory Type | OTP (One-Time Programmable) EPROM |
| Program Memory Size | 32 KB (16K x 16) |
| Data RAM | 902 bytes |
| I/O Pins | 50 |
| Supply Voltage | 4.5 V to 5.5 V |
| Operating Temperature | -40 °C to +125 °C (E grade) |
| Package | 68-PLCC (24.23 x 24.23 mm) J-lead |
| Mounting Type | Surface Mount (PLCC socket or solder) |
| ADC | 8-channel, 10-bit (per family datasheet) |
| Peripherals | USART, CCP, comparators, timers |
| Instruction Set Size | 58 single-word instructions |
| Programming Method | OTP (factory or production programmer) |
| RoHS Status | Not specified in provided data |
PIC17C756AT-33E/L Pin Configuration
| Pin 1 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 2 | OSC2/CLKOUT — Oscillator output |
| Pin 3 | MCLR/VPP — Master clear reset / programming voltage |
| Pin 4 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Pin 5 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Pin 6 | RA2/AN2 — PORTA bit 2 / analog input 2 |
| Pin 7 | RA3/AN3/VREF+ — PORTA bit 3 / analog input 3 / ADC Vref+ |
| Pin 8 | RA4/AN4 — PORTA bit 4 / analog input 4 |
| Pin 9 | RA5/AN5/SS — PORTA bit 5 / analog input 5 / SPI slave select |
| Pin 10 | RA6 — PORTA bit 6 |
| Pin 11 | RA7 — PORTA bit 7 |
| Pin 12 | VSS — Ground reference |
| Pin 13 | VDD — Positive supply (5V) |
| Pin 14 | RB0/INT — PORTB bit 0 / external interrupt |
| Pin 15 | RB1 — PORTB bit 1 |
| Pin 16 | RB2 — PORTB bit 2 |
| Pin 17 | RB3 — PORTB bit 3 |
| Pin 18 | RB4 — PORTB bit 4 |
| Pin 19 | RB5 — PORTB bit 5 |
| Pin 20 | RB6 — PORTB bit 6 |
| Pin 21 | RB7 — PORTB bit 7 |
| 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 (5V) |
| 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 (5V) |
| Pin 42 | RE0 — PORTE bit 0 |
| Pin 43 | RE1 — PORTE bit 1 |
| Pin 44 | RE2 — PORTE bit 2 |
| Pin 45 | RE3 — PORTE bit 3 |
| Pin 46 | RE4 — PORTE bit 4 |
| Pin 47 | RE5 — PORTE bit 5 |
| Pin 48 | RE6 — PORTE bit 6 |
| Pin 49 | RE7 — PORTE bit 7 |
| Pin 50 | VSS — Ground |
| Pin 51 | VDD — Positive supply (5V) |
| Pin 52 | RF0 — PORTF bit 0 |
| Pin 53 | RF1 — PORTF bit 1 |
| Pin 54 | RF2 — PORTF bit 2 |
| Pin 55 | RF3 — PORTF bit 3 |
| Pin 56 | RF4 — PORTF bit 4 |
| Pin 57 | RF5 — PORTF bit 5 |
| Pin 58 | RF6 — PORTF bit 6 |
| Pin 59 | RF7 — PORTF bit 7 |
| Pin 60 | VSS — Ground |
| Pin 61 | VDD — Positive supply (5V) |
| 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 | TOCKI — Timer0 clock input |
| Pin 68 | NC — Not connected (per datasheet) |
Typical Applications
PIC17C756AT-33E/L is suitable for 6 applications: Industrial Automation Controllers, Automotive Body Electronics, Consumer Appliance Control, Human-Machine Interface (HMI) Boards, Sensor Aggregation Nodes, Legacy PIC17C System Repair/Maintenance.
Industrial Automation Controllers
The PIC17C756AT-33E/L fits industrial PLC and machine-controller boards where its 50 digital I/O channels, 8.25 MIPS throughput, and -40 °C to +125 °C extended temperature grade ensure reliable operation on factory floors. Its 32 KB OTP holds ladder-logic-equivalent state machines and PID loop code, while the 902-byte RAM is ample for sensor-fusion buffers and communication stacks. The 33 MHz CPU comfortably services RS-485/USART polling of remote I/O at sub-millisecond cycle times.
Recommended
Automotive Body Electronics
PIC17C756AT-33E/L's automotive-grade extended temperature rating (-40 °C to +125 °C) and 50 I/O make it suitable for body controllers managing lighting, door modules, seat controllers, and climate subsystems. The 33 MHz core executes CAN-style message debouncing, PWM-driven mirror/headlamp control, and LIN-bus state machines in real time. OTP memory locks firmware against unintended field reprogramming in safety-relevant modules.
Recommended
Consumer Appliance Control
PIC17C756AT-33E/L's 32 KB OTP and 50 I/O deliver cost-effective control for washing machines, microwave ovens, dishwashers, and HVAC indoor units. The MCU drives keypads, character LCDs via I/O expansion, triac-fired loads through zero-cross detection, and sensor interfaces for temperature/pressure monitoring. OTP programming locks production firmware and prevents unauthorized cloning of branded appliance algorithms.
Recommended
Human-Machine Interface (HMI) Boards
The PIC17C756AT-33E/L drives 4x4 keypads, rotary encoders, LED/LCD status indicators, and segment displays in industrial HMI terminals. With 50 I/O and 8.25 MIPS, the MCU scans key matrices at >100 Hz, debounces mechanical contacts, and refreshes multiplexed 7-segment or character displays without flicker. The 902-byte RAM holds menu state and input buffers.
Recommended
Sensor Aggregation Nodes
PIC17C756AT-33E/L aggregates inputs from multiple analog and digital sensors in environmental monitoring and building automation. The 8-channel 10-bit ADC handles thermistor, photocell, and 4-20 mA transducer inputs, while USART and I/O ports forward conditioned data to upstream controllers. The 33 MHz CPU runs digital filters (averaging, peak detection) without burdening host systems.
Recommended
Legacy PIC17C System Repair/Maintenance
PIC17C756AT-33E/L is the canonical replacement for legacy PIC17C-based equipment in field service operations. Its identical silicon and 68-PLCC package allow direct board-level swap into industrial controllers, scientific instruments, and medical devices originally built around the PIC17C756A. Maintaining a small inventory of this OTP MCU supports 10-15 year service contracts on deployed systems where redesign is uneconomical.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C756AT-33E/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C756AT-33/L | PIC17C756AT-33I/L | PIC17C756A-33I/L | PIC17C756AT-16/L | PIC17C752T-33/L | PIC17C756A-33E/L |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 68-PLCC (24.23x24.23 mm) | 68-PLCC - same | 68-PLCC - same | 68-PLCC - same | 68-PLCC - same | 68-PLCC - same | 68-PLCC - same |
| Program Memory | 32 KB OTP | 32 KB OTP | 32 KB OTP | 32 KB OTP | 32 KB OTP | 32 KB OTP | 32 KB OTP |
| Max Clock | 33 MHz | 33 MHz | 33 MHz | 33 MHz | 16 MHz | 33 MHz | 33 MHz |
| Throughput | 8.25 MIPS | 8.25 MIPS | 8.25 MIPS | 8.25 MIPS | 4 MIPS | 8.25 MIPS | 8.25 MIPS |
| RAM | 902 bytes | 902 bytes | 902 bytes | 902 bytes | 902 bytes | 902 bytes | 902 bytes |
| I/O Pins | 50 | 50 | 50 | 50 | 50 | 50 | 50 |
| Operating Temperature | -40 °C to +125 °C (E grade) | 0 °C to +70 °C (commercial) | -40 °C to +85 °C (industrial) | -40 °C to +85 °C (industrial) | -40 °C to +125 °C (E grade) | -40 °C to +125 °C (E grade) | -40 °C to +125 °C (E grade) |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete |
Key Differentiators
- Extended -40 °C to +125 °C automotive/industrial temperature grade in 68-PLCC (vs PIC17C756AT-33/L)
- Tape-and-reel packaging for high-volume SMT production (vs PIC17C756A-33E/L)
- Same 68-PLCC footprint as the broader PIC17C family (vs PIC17C756AT-33E/PT (64-TQFP))
Design Notes
PIC17C756AT-33E/L requires a stable 4.5 V to 5.5 V supply. Place a 10 µF bulk electrolytic or tantalum and a 100 nF ceramic decoupling capacitor within 5 mm of each VDD pin pair. The 68-PLCC has multiple VDD/VSS pairs (pins 13/12, 31/30, 41/40, 51/50, 61/60) that must each be decoupled - poor decoupling causes ADC noise and brown-out resets. Use a ferrite bead on the analog AVDD rail if present in your schematic.
Do not confuse the OTP (PIC17C) family with the flash (PIC17F) or PIC18F families - code compiled for PIC17C will not run on PIC18F and vice versa. When migrating legacy code, recompile with the PIC18F compiler. OTP parts can only be programmed once - verify firmware with a windowed PIC17C756A version (PIC17C756A-EMR family) before committing to OTP production units.
PIC17C756AT-33E/L in 68-PLCC has a thermal resistance of approximately 50 °C/W (junction-to-ambient, still air) per Microchip plastic-package thermal data. At maximum clock and full I/O switching, power dissipation stays well under 500 mW. The PLCC package's top surface allows socket insertion for prototypes - useful for field-service repair kits where the MCU is field-swappable.
Compliance Information
RoHS, REACH, and halogen-free status not specified in the provided data. This part pre-dates Microchip's RoHS transition programs. AEC-Q100 status not explicitly stated; the E temperature grade (-40 to +125 °C) is automotive-grade rated but not formally Q100-qualified per the provided sources.
