PIC17LC756AT-08/PT - 8-bit 8MHz 32KB OTP MCU TQFP-64 | Microchip
MPN: PIC17LC756AT-08/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $14.5 | $14.50 |
| 10 | $12.95 | $129.50 |
| 100 | $11.4 | $1,140.00 |
| 500 | $9.85 | $4,925.00 |
| 1,000 | $8.6 | $8,600.00 |
PIC17LC756AT-08/PT Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory, working RAM, and peripheral interfaces. It belongs to the broader category of embedded processors -> microcontrollers -> 8-bit microcontrollers, and serves as the central control element in countless embedded systems where deterministic, low-power control is more important than raw compute throughput. The PIC17C family specifically targets high-performance 8-bit applications that exceed the capability of baseline PIC16 devices while retaining the simple RISC instruction set.
Key differentiating features include the 16-bit-wide instruction word (vs. 14-bit on PIC16), which permits richer addressing modes and larger immediate operands, a hardware multiply option, and dual-cycle branch execution that gives 8 MHz clocking an effective throughput comparable to many 16 MHz PIC16 designs. The OTP memory enables fast prototype-to-production transition, while the wide VCC tolerance (2.5 V to 5.5 V) supports both 3.3 V and 5 V system rails.
Typical applications for the PIC17LC756AT-08/PT include industrial control panels, motor-drive front-end controllers, automotive body electronics, white-goods user interfaces, and legacy embedded products that were originally designed around the PIC17C architecture. The 64-pin TQFP package offers generous I/O and peripheral count for mid-complexity designs.
A key design consideration is the OTP memory nature: firmware must be fully validated before programming because the device cannot be erased. Engineers migrating to flash-based PIC18 or dsPIC33 families should evaluate whether legacy code constraints justify retention of this OTP PIC17C part, or whether a modern flash MCU is more appropriate.
This page synthesizes distributor pricing, verified cross-reference data, and practical design guidance not aggregated on the manufacturer datasheet, helping engineers and procurement teams evaluate the PIC17LC756AT-08/PT for both new designs and legacy board replacements.
Drop-in alternatives for PIC17LC756AT-08/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 PIC17LC756AT-08/PT (same form factor and footprint) — differing in Core Architecture, Data Bus Width, I/O Pins, Program Memory Type, Maximum Clock Frequency.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17LC756A-08/PT
✅ Drop-In✓ In Stock
$7.8 / Unit
View Datasheet →PIC17LC756AT-08I/PT
✅ Drop-In✓ In Stock
$8.4 / Unit
View Datasheet →PIC17LC756A-08I/PT
✅ Drop-In✓ In Stock
$12.3 / Unit
View Datasheet →PIC17C756A-16/PT
✅ Drop-In✓ In Stock
$11.95 / Unit
View Datasheet →PIC17C756AT-16/PT
✅ Drop-In✓ In Stock
$11.95 / Unit
View Datasheet →PIC17C756A-33E/PT
✅ Drop-In✓ In Stock
$7.55 / Unit
View Datasheet →PIC17LC756AT-08/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC |
| Family | PIC17C |
| CPU Bit Width | 8-bit (16-bit instruction word) |
| Maximum Clock Frequency | 8 MHz |
| Instruction Cycle Time | 121 ns (single cycle, except branches and table reads/writes) |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 32 KB (16K x 16) |
| Data Bus Width | 16-bit |
| RAM Size | 902 bytes |
| I/O Pins | 33 |
| Supply Voltage (VCC) | 2.5 V to 5.5 V |
| Communication Interfaces | I2C, SPI, UART/USART |
| Instruction Set Size | 58 single-word instructions |
| Package | 64-pin TQFP (10x10 mm) |
| Mounting Type | Surface Mount |
| RoHS Status | Lead free / RoHS Compliant |
PIC17LC756AT-08/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) |
| Pin 9 | RA5 — Port A bit 5 (digital I/O) |
| Pin 10 | VSS — Ground |
| Pin 11 | VDD — Positive supply voltage |
| Pin 12 | RB0 — Port B bit 0 (digital I/O / external interrupt) |
| Pin 13 | RB1 — Port B bit 1 (digital I/O) |
| 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 / programming clock) |
| Pin 19 | RB7 — Port B bit 7 (digital I/O / programming data) |
| Pin 20 | VSS — Ground |
| Pin 21 | VDD — Positive supply voltage |
| Pin 22 | RC0 — Port C bit 0 (digital I/O) |
| Pin 23 | RC1 — Port C bit 1 (digital I/O) |
| Pin 24 | RC2 — Port C bit 2 (digital I/O) |
| Pin 25 | RC3 — Port C bit 3 (digital I/O) |
| Pin 26 | RC4 — Port C bit 4 (digital I/O) |
| Pin 27 | RC5 — Port C bit 5 (digital I/O) |
| Pin 28 | RC6 — Port C bit 6 (digital I/O / TX) |
| Pin 29 | RC7 — Port C bit 7 (digital I/O / RX) |
| Pin 30 | RD0 — Port D bit 0 (digital I/O) |
| Pin 31 | RD1 — Port D bit 1 (digital I/O) |
| Pin 32 | RD2 — Port D bit 2 (digital I/O) |
| Pin 33 | RD3 — Port D bit 3 (digital I/O) |
| Pin 34 | RD4 — Port D bit 4 (digital I/O) |
| Pin 35 | RD5 — Port D bit 5 (digital I/O) |
| Pin 36 | RD6 — Port D bit 6 (digital I/O) |
| Pin 37 | RD7 — Port D bit 7 (digital I/O) |
| Pin 38 | VSS — Ground |
| Pin 39 | VDD — Positive supply voltage |
| Pin 40 | RE0 — Port E bit 0 (digital I/O) |
| Pin 41 | RE1 — Port E bit 1 (digital I/O) |
| Pin 42 | RE2 — Port E bit 2 (digital I/O) |
| Pin 43 | RE3 — Port E bit 3 (digital I/O) |
| Pin 44 | RE4 — Port E bit 4 (digital I/O) |
| Pin 45 | RE5 — Port E bit 5 (digital I/O) |
| Pin 46 | RE6 — Port E bit 6 (digital I/O) |
| Pin 47 | RE7 — Port E bit 7 (digital I/O) |
| Pin 48 | VSS — Ground |
| Pin 49 | VDD — Positive supply voltage |
| Pin 50 | RF0 — Port F bit 0 (digital I/O) |
| Pin 51 | RF1 — Port F bit 1 (digital I/O) |
| Pin 52 | RF2 — Port F bit 2 (digital I/O) |
| Pin 53 | RF3 — Port F bit 3 (digital I/O) |
| Pin 54 | RF4 — Port F bit 4 (digital I/O) |
| Pin 55 | RF5 — Port F bit 5 (digital I/O) |
| Pin 56 | RF6 — Port F bit 6 (digital I/O) |
| Pin 57 | RF7 — Port F bit 7 (digital I/O) |
| Pin 58 | SDA — I2C serial data |
| Pin 59 | SCL — I2C serial clock |
| Pin 60 | SDO — SPI serial data out |
| Pin 61 | SDI — SPI serial data in |
| Pin 62 | SCK — SPI serial clock |
| Pin 63 | TX — UART transmit |
| Pin 64 | RX — UART receive |
Typical Applications
PIC17LC756AT-08/PT is suitable for 6 applications: Industrial Control Panels, Motor Drive Front-End Controller, Automotive Body Electronics, White Goods User Interface Controller, Legacy Embedded Replacement Board, Smart Sensor Aggregator.
Industrial Control Panels
The PIC17LC756AT-08/PT's 8-bit RISC core, 32 KB OTP program memory, and 33 I/O pins make it well-suited for industrial control panel applications including HMI button scanning, relay/SSR drivers, and discrete sensor aggregation. The 16-bit instruction word delivers high code density for ladder-logic-style state machines, while the 2.5 V to 5.5 V supply tolerance accepts both 3.3 V and 5 V backplane rails common in industrial PLC and machine-controller designs. The 121 ns instruction cycle supports deterministic scan loops below 1 ms, which is adequate for most discrete control tasks. Hardware I2C and SPI peripherals connect to digital sensor front-ends and display drivers without external glue logic. Note: the OTP memory nature means firmware must be fully validated and burned only once; revision management requires board rework or inventory rotation.
Recommended
Motor Drive Front-End Controller
The PIC17LC756AT-08/PT can serve as the supervisory front-end controller in variable-frequency drives and stepper/servo systems where it handles user inputs, safety interlocks, and command parsing before delegating real-time commutation to a dedicated motor controller. Its 33 I/O lines accommodate enable inputs, fault feedback from gate drivers, brake control outputs, and PWM handshake signals. The 8 MHz CPU throughput supports inner control loops up to ~2 kHz, sufficient for command shaping and protection logic in BLDC and stepper systems. Hardware UART/USART enables RS-232/485 communication with supervisory PLCs or HMIs. The 64-pin TQFP package provides sufficient I/O count for multi-axis front-end controllers without requiring port expanders.
Recommended
Automotive Body Electronics
The PIC17LC756AT-08/PT is appropriate for non-safety automotive body modules such as interior lighting controllers, seat-position memory, mirror adjustment, and accessory multiplexers where its 33 I/O pins handle multiple low-side/high-side driver controls. The wide 2.5 V to 5.5 V supply tolerance accommodates 12 V battery feeds after pre-regulation, and the 902-byte RAM supports CAN-style command buffers when paired with an external CAN transceiver. Note: for AEC-Q100 qualified designs, use the industrial-temperature -I variants. The OTP memory is acceptable for high-volume production runs where firmware revision churn is low and validated firmware is burned only once. Modern designs should migrate to PIC18F or dsPIC33 families with flash memory and CAN peripherals integrated.
Recommended
White Goods User Interface Controller
The PIC17LC756AT-08/PT fits white-goods appliance user-interface designs (washing machines, dishwashers, microwave ovens) where it scans keypad/rotary-encoder inputs, drives 7-segment or character LCD displays, and coordinates timing for heating, pumping, and motor subsystems. Its 32 KB OTP holds complete appliance state machines including wash-cycle profiles and fault logs, while 902 bytes RAM supports run-time cycle variables and EEPROM emulation. The 8 MHz throughput is more than sufficient for human-interface reaction times (sub-100 ms). I2C and SPI peripherals connect to temperature sensors, RTC chips, and LED driver ICs. The 64-pin TQFP package suits main control boards in mid-size appliances where pad count is plentiful.
Recommended
Legacy Embedded Replacement Board
The PIC17LC756AT-08/PT is commonly used as a like-for-like replacement for original PIC17C756A-series boards in legacy products where the firmware has been validated and cannot be re-qualified, and the 64-pin TQFP footprint is already laid out on the PCB. Microchip has placed this part in NRND status but continues to ship for sustainment purposes. Designers maintaining installed-base equipment benefit from identical pinout, identical peripherals, and identical instruction set across the OTP part and flash-based PIC17C76x successors, simplifying board-level drop-in substitution. The 8 MHz CPU maintains backwards-compatible timing for legacy communication stacks and control loops.
Recommended
Smart Sensor Aggregator
The PIC17LC756AT-08/PT can aggregate multiple analog and digital sensors in industrial IoT edge nodes, where it performs sensor polling, threshold detection, and protocol framing before forwarding via UART to a higher-level gateway. The 33 digital I/O lines accommodate SPI/I2C sensor clusters, while the 8 MHz CPU handles sampling-rate scheduling and basic digital filtering. The 902-byte RAM supports circular buffers for sensor data and command frames. The 2.5 V to 5.5 V supply range accepts power directly from 3.3 V LDO outputs of typical sensor-module designs. For new IoT designs, consider migrating to PIC18F or dsPIC33 families with integrated CAN, USB, or Ethernet peripherals.
Recommended
Recommended Products Summary
Engineering reference data for PIC17LC756AT-08/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17LC756A-08/PT | PIC17LC756AT-08I/PT | PIC17LC756A-08I/PT | PIC17C756A-16/PT | PIC17C756AT-16/PT | PIC17C756A-33E/PT |
|---|---|---|---|---|---|---|---|
| Package | 64-pin TQFP (10x10) | 64-pin TQFP (10x10) - same | 64-pin TQFP (10x10) - same | 64-pin TQFP (10x10) - same | 64-pin TQFP (10x10) - same | 64-pin TQFP (10x10) - same | 64-pin TQFP (10x10) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Type | OTP (32 KB) | OTP (32 KB) | OTP (32 KB) | OTP (32 KB) | Flash (32 KB) | Flash (32 KB) | Flash (32 KB) |
| Maximum CPU Clock | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 16 MHz | 16 MHz | 33 MHz |
| RAM Size | 902 bytes | 902 bytes | 902 bytes | 902 bytes | 902 bytes | 902 bytes | 902 bytes |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 | 33 |
| Supply Voltage | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 4.5 V to 5.5 V (typical) | 4.5 V to 5.5 V (typical) | 4.5 V to 5.5 V (typical) |
| Temperature Grade | Commercial | Commercial | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Commercial | Commercial | Extended (-40C to +125C) |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | NRND | NRND |
Key Differentiators
- 16-bit instruction word architecture delivers higher code density (vs PIC16F877A)
- 33 I/O pins in 64-pin TQFP without port expander (vs PIC16F877A (40-pin DIP))
- Drop-in compatible flash upgrade path exists within same package (vs PIC18F alternatives)
Design Notes
OTP memory cannot be erased or rewritten. Once programmed, the PIC17LC756AT-08/PT cannot be re-flashed; any firmware bug requires board-level rework or part replacement. For new designs and field-upgradable products, migrate to the flash-based PIC17C756A-16/PT or PIC17C766 family. Validate firmware thoroughly using a PIC17C76x flash prototype before committing the OTP part to volume production.
The 64-pin TQFP package requires multiple VDD/VSS pin pairs (typically pins 11/10, 21/20, 39/38, 49/48) for proper power distribution. Decouple each VDD pin with a 100 nF ceramic capacitor placed as close to the IC as possible. Add a single bulk 10 uF tantalum or ceramic capacitor on the main supply rail to handle transient current demands during peripheral switching.
TQFP-64 packages have 0.5 mm pitch leads that require careful PCB layout: use solder paste stencil apertures slightly reduced from pad size (typically 90%) to prevent bridging, ensure proper thermal relief on through-hole pads, and follow JEDEC MS-026 land pattern recommendations. Maintain 0.2 mm clearance between adjacent pads and keep trace widths under 0.25 mm in the lead fanout area.
The PIC17LC756AT-08/PT oscillator pins (OSC1/OSC2) should be routed with short, parallel traces to the crystal or resonator, with a ground guard ring or poured ground plane to minimize noise coupling. Place load capacitors within 3 mm of the OSC pins. Avoid routing high-frequency signals (UART, SPI) parallel to the oscillator traces to prevent clock jitter and EMI issues.
The MCLR reset pin on the PIC17LC756AT-08/PT requires a 10 kohm pull-up resistor to VDD for normal operation. For noise-sensitive environments, add a 100 nF capacitor from MCLR to ground to filter fast transients. The ICSP (In-Circuit Serial Programming) pins RB6/RB7 share functions with general-purpose I/O; ensure pull-ups or proper isolation if these pins are used for external loads during programming.
Compliance Information
RoHS compliant and lead-free per Microchip product page. Not AEC-Q100 qualified; the -I industrial grade variant extends operating temperature to -40C to +85C but is not automotive-qualified. For AEC-Q100 applications, consider dsPIC33EV automotive family.
