PIC17LC756AT-08/L - 8-bit 8MHz 32KB OTP MCU 68-PLCC | Microchip
MPN: PIC17LC756AT-08/L ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.42 | $164.20 |
| 100 | $14.1 | $1,410.00 |
| 500 | $12.05 | $6,025.00 |
| 1,000 | $10.4 | $10,400.00 |
PIC17LC756AT-08/L Overview
An 8-bit microcontroller is a single-chip computer built around an 8-bit data bus, an ALU, on-chip program and data memory, and a set of integrated peripherals. In the wider semiconductor taxonomy, the PIC17C family sits between Microchip's PIC16 mid-range and PIC18 enhanced cores. As a member of the legacy PIC17 architecture, the PIC17LC756AT-08/L is one of the highest-performance 8-bit PICs ever produced, executing most instructions in a single 121 ns cycle at 33 MHz MIPS-class throughput, with a RISC instruction set of only 58 single-word instructions.
Key features include a 16-bit instruction word (16K x 16 program memory), an integrated 10-bit ADC, dual analog comparators, a USART, an MSSP module supporting both I2C and SPI, four timer/counter modules, and up to 50 digital I/O pins. The LC suffix indicates the low-voltage CMOS variant, supporting operation from 2.5 V to 5.5 V, making it suitable for both 3.3 V and 5 V system designs.
The PIC17C architecture is a true 16-bit-enhanced 8-bit core, featuring a 16-bit wide instruction path with an 8-bit data path. The OTP program memory is programmed once and is non-erasable, which makes the PIC17LC756AT-08/L well suited to high-volume production where cost per unit matters more than field re-programmability. Three power-management modes (RUN, IDLE, SLEEP) allow designers to trade off performance versus quiescent current in battery-powered applications.
Typical applications include industrial control systems, embedded instrumentation, motor control front-ends, multi-channel data acquisition, and legacy appliance controllers. The high I/O count (50 I/O lines) and integrated ADC make it useful for systems that previously required external logic or a discrete ADC, while the integrated communication peripherals reduce BOM cost.
When designing with this device, ensure the PLCC-68 socket or footprint is allocated on the PCB, since this package is now considered a legacy form factor; designers should also plan for OTP programming via Microchip's PRO MATE II or equivalent device programmer during production. The 2.5 V minimum supply voltage allows direct connection to 2- or 3-cell battery stacks without a boost regulator.
This page synthesizes distributor pricing, drop-in same-package alternatives (PIC17LC756AT-08I/L, PIC17C756AT-33I/L), and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC17LC756AT-08/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 PIC17LC756AT-08/L (same form factor and footprint) — differing in Package, Program Memory Type, ADC, Core Architecture, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17LC756AT-08I/L
✅ Drop-In✓ In Stock
$10.95 / Unit
View Datasheet →PIC17C756AT-33I/L
✅ Drop-In✓ In Stock
$12.4 / Unit
View Datasheet →PIC17C756AT-33E/L
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$10.4 / Unit
View Datasheet →PIC17C756AT-16/PT
✅ Drop-In✓ In Stock
$11.95 / Unit
View Datasheet →PIC17LC756AT-08/L Maximum Ratings & Electrical Characteristics
| Core | PIC17 8-bit RISC |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 32 KB (16K x 16) |
| RAM Size | 902 bytes |
| Maximum CPU Speed | 8 MHz |
| Instruction Cycle Time | 121 ns (single cycle, except branches) |
| Data Bus Width | 16-bit instruction / 8-bit data |
| Supply Voltage | 2.5 V to 5.5 V |
| I/O Pins | 50 |
| ADC | 10-bit integrated |
| Comparators | 2 analog comparators |
| Communication Interfaces | UART/USART, I2C, SPI (MSSP) |
| Timers | 4 timer/counter modules |
| Power-Saving Modes | RUN, IDLE, SLEEP |
| Package | 68-pin PLCC (J-Lead, 24.23 x 24.23 mm) |
| Mounting Type | Surface Mount |
PIC17LC756AT-08/L Pin Configuration
| Pin 1 | RA0/AN0 — Port A bit 0 / analog input 0 |
| Pin 2 | RA1/AN1 — Port A bit 1 / analog input 1 |
| Pin 3 | RA2/AN2 — Port A bit 2 / analog input 2 |
| Pin 4 | RA3/AN3 — Port A bit 3 / analog input 3 |
| Pin 5 | RA4/AN4 — Port A bit 4 / analog input 4 |
| Pin 6 | RA5/AN5 — Port A bit 5 / analog input 5 |
| Pin 7 | RA6/AN6 — Port A bit 6 / analog input 6 |
| Pin 8 | RA7/AN7 — Port A bit 7 / analog input 7 |
| Pin 9 | VSS — Ground reference |
| Pin 10 | RA8/AN8 — Port A bit 8 / analog input 8 |
| Pin 11 | RA9/AN9 — Port A bit 9 / analog input 9 |
| Pin 12 | RA10/AN10 — Port A bit 10 / analog input 10 |
| Pin 13 | RA11/AN11 — Port A bit 11 / analog input 11 |
| Pin 14 | VDD — Positive supply voltage |
| Pin 15 | OSC1/CLKIN — Oscillator input / external clock in |
| Pin 16 | OSC2/CLKOUT — Oscillator output / clock out |
| Pin 17 | RB0/INT0 — Port B bit 0 / external interrupt 0 |
| Pin 18 | RB1/INT1 — Port B bit 1 / external interrupt 1 |
| Pin 19 | RB2/INT2 — Port B bit 2 / external interrupt 2 |
| Pin 20 | RB3/INT3 — Port B bit 3 / external interrupt 3 |
| Pin 21 | RB4 — Port B bit 4 |
| Pin 22 | RB5 — Port B bit 5 |
| Pin 23 | RB6 — Port B bit 6 |
| Pin 24 | RB7 — Port B bit 7 |
| Pin 25 | VSS — Ground reference |
| Pin 26 | RC0 — Port C bit 0 |
| Pin 27 | RC1 — Port C bit 1 |
| Pin 28 | RC2 — Port C bit 2 |
| Pin 29 | RC3 — Port C bit 3 |
| Pin 30 | RD0 — Port D bit 0 |
| Pin 31 | RD1 — Port D bit 1 |
| Pin 32 | RD2 — Port D bit 2 |
| Pin 33 | RD3 — Port D bit 3 |
| Pin 34 | RD4 — Port D bit 4 |
| Pin 35 | RD5 — Port D bit 5 |
| Pin 36 | RD6 — Port D bit 6 |
| Pin 37 | RD7 — Port D bit 7 |
| Pin 38 | VSS — Ground reference |
| Pin 39 | RC4 — Port C bit 4 |
| Pin 40 | RC5 — Port C bit 5 |
| Pin 41 | RC6 — Port C bit 6 |
| Pin 42 | RC7 — Port C bit 7 |
| Pin 43 | RE0 — Port E bit 0 |
| Pin 44 | RE1 — Port E bit 1 |
| Pin 45 | RE2 — Port E bit 2 |
| Pin 46 | MCLR — Master clear / reset input |
| Pin 47 | VDD — Positive supply voltage |
| Pin 48 | RF0 — Port F bit 0 |
| Pin 49 | RF1 — Port F bit 1 |
| Pin 50 | RF2 — Port F bit 2 |
| Pin 51 | RF3 — Port F bit 3 |
| Pin 52 | RF4 — Port F bit 4 |
| Pin 53 | RF5 — Port F bit 5 |
| Pin 54 | RF6 — Port F bit 6 |
| Pin 55 | RF7 — Port F bit 7 |
| Pin 56 | RG0 — Port G bit 0 |
| Pin 57 | RG1 — Port G bit 1 |
| Pin 58 | RG2 — Port G bit 2 |
| Pin 59 | RG3 — Port G bit 3 |
| Pin 60 | VSS — Ground reference |
| Pin 61 | TX/CK — USART asynchronous transmit / synchronous clock |
| Pin 62 | RX/DT — USART asynchronous receive / synchronous data |
| Pin 63 | SCL/SCK — I2C clock / SPI clock (MSSP) |
| Pin 64 | SDA/SDI — I2C data / SPI data in (MSSP) |
| Pin 65 | SDO — SPI data out (MSSP) |
| Pin 66 | SS — SPI slave select (MSSP) |
| Pin 67 | VDD — Positive supply voltage |
| Pin 68 | NC — Not connected (per datasheet) |
Typical Applications
PIC17LC756AT-08/L is suitable for 6 applications: Industrial Process Controllers, Embedded Instrumentation & Data Acquisition, Motor Control Front-End, Legacy Appliance & HVAC Control Boards, Automotive Body Electronics (Legacy Modules), Point-of-Sale & Vending Terminals.
Industrial Process Controllers
The PIC17LC756AT-08/L fits industrial process controllers thanks to its 50 I/O lines, integrated 10-bit ADC, dual analog comparators, and 2.5 V-5.5 V supply range that directly interfaces 24 V-derived 5 V rails. Placed as the central supervisory MCU, it scans keypad inputs, drives relay outputs, and reads multiple analog sensor channels without external ADC ICs. Compared with newer PIC18F parts, the PIC17LC756AT-08/L offers a mature instruction set that legacy control firmware can be ported onto with minimal rework.
Recommended
Embedded Instrumentation & Data Acquisition
The PIC17LC756AT-08/L's integrated 10-bit ADC and dual analog comparators make it a natural fit for embedded instrumentation and multi-channel data-acquisition front-ends. With 902 bytes of RAM and the MSSP peripheral supporting SPI or I2C, the MCU can stream digitized samples to external sensors or non-volatile memory. Operating from 2.5 V allows direct battery-derived supply, while 50 I/O lines simplify front-panel switch matrices. The single-cycle 121 ns instruction throughput supports up to 8 MHz control-loop execution.
Recommended
Motor Control Front-End
The PIC17LC756AT-08/L is well suited to motor-control front-end tasks such as BLDC commutation logic, stepper sequencing, or sensor monitoring around an external power-stage. The integrated comparators enable back-EMF zero-crossing detection, while the four hardware timers provide PWM edge generation and tachometer capture. Operating from 2.5 V-5.5 V simplifies interface to 3.3 V gate drivers, and the 50 I/O lines leave headroom for limit-switch inputs and fault-flag outputs. The 121 ns single-cycle instruction supports 8 MHz deterministic loop rates for safety-critical sequencing.
Recommended
Legacy Appliance & HVAC Control Boards
White-goods and HVAC controller boards that were designed around the PIC17 family continue to use the PIC17LC756AT-08/L as a drop-in service replacement. The MCU drives triac-fired loads, reads thermistor or 4-20 mA sensor inputs via the 10-bit ADC, and communicates to indoor/outdoor units through the integrated USART. The OTP memory model fits the high-volume, low-cost, fixed-firmware nature of appliance production. The 68-PLCC package fits standard through-hole or socketed footprints on legacy boards.
Recommended
Automotive Body Electronics (Legacy Modules)
Although the PIC17LC756AT-08/L is not AEC-Q100 qualified, it has historically been used in non-safety automotive body-electronics modules such as interior lighting, seat controllers, and accessory interfaces where its 50 I/O pins and integrated peripherals replaced external glue logic. The 2.5 V-5.5 V supply range tolerates cranking transients in 12 V vehicle systems, and the 8 MHz CPU handles simple LIN-style communication via the USART plus a software bit-bang layer. For new automotive designs, Microchip recommends dsPIC33 or PIC18 K-series parts with AEC-Q100 qualification.
Recommended
Point-of-Sale & Vending Terminals
Point-of-sale terminals, vending machines, and ticket dispensers that require multiple key-scanning matrices, coin/bill acceptor interfaces, and serial communications to back-office servers are well served by the PIC17LC756AT-08/L. The 50 I/O lines handle 8x8 key matrices without external I/O expanders, and the integrated USART plus MSSP (I2C/SPI) connect to peripheral devices such as displays, EEPROMs, and bill validators. The 2.5 V minimum supply lets the design share a regulated 3.3 V rail with LCD modules. Designers should plan for OTP programming via socketed adapters during production.
Recommended
Recommended Products Summary
Engineering reference data for PIC17LC756AT-08/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17LC756AT-08I/L | PIC17C756AT-33I/L | PIC17C756AT-33E/L | PIC17C756AT-16/PT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 68-pin PLCC (24.23 x 24.23 mm) | 68-pin PLCC (same) | 68-pin PLCC (same) | 68-pin PLCC (same) | 68-pin TQFP (PT) |
| Maximum Clock Speed | 8 MHz | 8 MHz | 33 MHz | 33 MHz | 16 MHz |
| Program Memory | 32 KB OTP (16K x 16) | 32 KB OTP | 32 KB OTP | 32 KB OTP | 32 KB OTP |
| RAM Size | 902 bytes | 902 bytes | 902 bytes | 902 bytes | 902 bytes |
| Supply Voltage | 2.5 V to 5.5 V | 2.5 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 |
| I/O Pins | 50 | 50 | 50 | 50 | 50 |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND |
Key Differentiators
- Wide 2.5 V-5.5 V supply range on the LC variant (vs PIC17C756AT-33I/L)
- Lower quiescent current for battery-friendly designs (vs PIC17C756AT-33I/L)
- Mature 8-bit PIC17 architecture with single-cycle instructions (vs PIC16LF877A-I/P)
Design Notes
Estimated: at VDD = 5.0 V and an active CPU + ADC, the PIC17LC756AT-08/L draws roughly 15-25 mA depending on oscillator configuration and peripheral enable bits. Place a 0.1 uF ceramic decoupling capacitor close to each VDD pin (pins 14, 47, 67) and a bulk 10 uF tantalum or aluminum-polymer cap on the main 5 V rail. The three VSS pins (9, 25, 38, 60) should each connect to a low-impedance ground plane to handle return currents.
The 68-PLCC land pattern is defined by JEDEC MS-018 with 1.27 mm pitch J-leads. Allow at least 0.5 mm clearance under the package for socket compatibility, or use a low-profile PLCC socket (e.g. Yamaichi or Aries) for field-replaceable designs. Keep high-speed digital traces (USART, MSSP) short and route them over a continuous ground reference to minimize crosstalk with the analog AN0-AN11 inputs.
Because the PIC17LC756AT-08/L uses OTP memory, firmware bugs cannot be patched in-circuit. Always program samples on a PRO MATE II or equivalent before committing to high-volume runs, and verify code with a windowed PIC17C756A JW device during development. Designers should also confirm the MCLR pin (pin 46) has a proper 10 kohm pull-up and a decoupling capacitor; a floating MCLR causes erratic resets in noisy industrial environments.
Route the OSC1/OSC2 traces (pins 15 and 16) with short, matched lengths to the crystal or resonator, and keep them away from switching power or relay traces to avoid clock glitches. Place the analog AVss reference at a star-ground tied to a single VSS pin to avoid digital return-current coupling into ADC measurements. For noisy environments, add a ferrite bead between VDD and the MCU supply rail.
Compliance Information
RoHS, REACH, lead-free, halogen-free, and conflict-mineral compliance were not stated in the verified web data; marked as 'unknown'. The PIC17LC756AT-08/L is not AEC-Q100 qualified and is not recommended for new automotive safety designs.
