PIC17C756AT-16E/L - 8-Bit 16MHz OTP MCU, 32KB, 68-PLCC | Microchip
MPN: PIC17C756AT-16E/L ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $22.5 | $22.50 |
| 10 | $20.25 | $202.50 |
| 100 | $17.8 | $1,780.00 |
| 500 | $15.6 | $7,800.00 |
| 1,000 | $13.95 | $13,950.00 |
PIC17C756AT-16E/L Overview
A microcontroller (MCU) is an integrated circuit that combines a CPU core, program memory, working RAM, and programmable I/O peripherals in a single chip. The PIC17C family is Microchip's highest-performance 8-bit architecture before the introduction of the PIC18 family, executing 8.25 MIPS at 16 MHz with only 58 single-word instructions and a deterministic 4-cycle pipeline. PIC MCUs sit within the broader hierarchy: microcontroller -> embedded processor -> semiconductor, and remain widely deployed in legacy industrial control, instrumentation, and automotive subsystems that depend on OTP-only code storage.
Key features of this part include a 16-bit data bus architecture, 50 programmable digital I/O lines, an integrated 10-bit analog-to-digital converter, USART, SSP, and capture/compare/PWM peripherals, and a supply voltage range of 4.5 V to 5.5 V. The 68-PLCC socket-mount package supports easy prototyping and field replacement in legacy designs. The extended temperature grade ('E') makes the part suitable for outdoor, automotive, and industrial environments. OTP program memory enables low per-unit cost for mature, fully validated firmware where no field updates are required.
Typical application domains include industrial process control, building automation controllers, motor drive front-ends, instrumentation front-panels, and white-goods control boards. Modern Microchip guidance recommends migrating to the PIC18F6520 (Flash-based) for new designs, but the PIC17C756AT-16E/L remains supported through the Microchip Legacy MCU program for existing production.
When designing with this device, ensure decoupling capacitors (typically 100 nF plus 10 uF bulk) are placed within 5 mm of VDD/VSS pins, and follow the 5V rail tolerance carefully because the part does not include an internal brown-out reset on all speed grades. Code development uses the MPLAB XC8 compiler and a 5V-tolerant ICSP programmer such as the PICkit 3.
Drop-in alternatives for PIC17C756AT-16E/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-16E/L (same form factor and footprint) — differing in Package, Program Memory Type, Operating Temperature, Mounting Type, A/D Converter.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C756A-16I/L
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View Datasheet →PIC17C756A-16E/PT
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View Datasheet →PIC17C756A-33E/L
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View Datasheet →PIC17C752T-33/L
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View Datasheet →PIC17C756AT-16/PT
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View Datasheet →PIC17C756AT-16E/L Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit (PIC17C family) |
| Instruction Set Width | 16-bit (data bus), 58 single-word instructions |
| Maximum CPU Clock | 16 MHz |
| Instruction Execution Time | 121 ns (8.25 MIPS) |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 32 KB (16K x 16) |
| Data RAM | 902 bytes |
| Supply Voltage (VDD) | 4.5 V to 5.5 V |
| I/O Pins | 50 (digital, programmable) |
| A/D Converter | 10-bit, integrated |
| Package | 68-pin PLCC (J-lead, 24.23 x 24.23 mm) |
| Mounting Type | Surface Mount / Socket (PLCC socket compatible) |
| Operating Temperature | -40 C to +125 C (Extended, 'E' suffix) |
| Peripherals | USART, SSP, Capture/Compare/PWM, Timers |
PIC17C756AT-16E/L Pin Configuration
| Pin 1 | OSC1/CLKI — Oscillator input / external clock |
| Pin 2 | OSC2/CLKO — Oscillator output |
| Pin 3 | MCLR — Master Clear (reset, active low) |
| 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 / VREF+ |
| Pin 8 | RA4/AN4 — PORTA bit 4 / Analog input 4 |
| Pin 9 | RA5/AN5 — PORTA bit 5 / Analog input 5 |
| Pin 10 | VDD — Logic power (5V) |
| Pin 11 | VSS — Ground |
| Pin 12 | RB0/INT — PORTB bit 0 / External interrupt |
| Pin 13 | RB1 — PORTB bit 1 |
| Pin 14 | RB2 — PORTB bit 2 |
| Pin 15 | RB3 — PORTB bit 3 |
| Pin 16 | RB4 — PORTB bit 4 |
| Pin 17 | RB5 — PORTB bit 5 |
| Pin 18 | RB6 — PORTB bit 6 |
| Pin 19 | RB7 — PORTB bit 7 |
| Pin 20 | RC0 — PORTC bit 0 |
| Pin 21 | RC1 — PORTC bit 1 |
| Pin 22 | RC2 — PORTC bit 2 |
| Pin 23 | RC3 — PORTC bit 3 |
| Pin 24 | RC4 — PORTC bit 4 |
| Pin 25 | RC5 — PORTC bit 5 |
| Pin 26 | RC6 — PORTC bit 6 |
| Pin 27 | RC7 — PORTC bit 7 |
| Pin 28 | RD0 — PORTD bit 0 |
| Pin 29 | RD1 — PORTD bit 1 |
| Pin 30 | RD2 — PORTD bit 2 |
| Pin 31 | RD3 — PORTD bit 3 |
| Pin 32 | RD4 — PORTD bit 4 |
| Pin 33 | RD5 — PORTD bit 5 |
| Pin 34 | RD6 — PORTD bit 6 |
| Pin 35 | RD7 — PORTD bit 7 |
| Pin 36 | RE0 — PORTE bit 0 |
| Pin 37 | RE1 — PORTE bit 1 |
| Pin 38 | RE2 — PORTE bit 2 |
| Pin 39 | RE3 — PORTE bit 3 |
| Pin 40 | RE4 — PORTE bit 4 |
| Pin 41 | RE5 — PORTE bit 5 |
| Pin 42 | RE6 — PORTE bit 6 |
| Pin 43 | RE7 — PORTE bit 7 |
| Pin 44 | VDD — Logic power (5V) |
| Pin 45 | VSS — Ground |
| Pin 46 | RF0 — PORTF bit 0 |
| Pin 47 | RF1 — PORTF bit 1 |
| Pin 48 | RF2 — PORTF bit 2 |
| Pin 49 | RF3 — PORTF bit 3 |
| Pin 50 | RF4 — PORTF bit 4 |
| Pin 51 | RF5 — PORTF bit 5 |
| Pin 52 | RF6 — PORTF bit 6 |
| Pin 53 | RF7 — PORTF bit 7 |
| Pin 54 | RG0 — PORTG bit 0 |
| Pin 55 | RG1 — PORTG bit 1 |
| Pin 56 | RG2 — PORTG bit 2 |
| Pin 57 | RG3 — PORTG bit 3 |
| Pin 58 | RG4 — PORTG bit 4 |
| Pin 59 | NC — Not connected |
| Pin 60 | NC — Not connected |
| Pin 61 | AVDD — Analog power |
| Pin 62 | AVSS — Analog ground |
| Pin 63 | VREF+ — ADC voltage reference + |
| Pin 64 | VREF- — ADC voltage reference - |
| Pin 65 | TX/CK — USART TX / clock |
| Pin 66 | RX/DT — USART RX / data |
| Pin 67 | SDA — I2C data |
| Pin 68 | SCL — I2C clock |
Typical Applications
PIC17C756AT-16E/L is suitable for 6 applications: Industrial Process Control, Building Automation Controllers, White Goods and Appliance Control, Automotive Body and Chassis Modules, Instrumentation and Test Equipment Front Panels, Motor Drive and PWM Control Front-Ends.
Industrial Process Control
The PIC17C756AT-16E/L fits industrial process-control PLCs and remote telemetry units because of its 50 programmable I/O lines (4 ports of GPIO), 16 MHz CPU delivering 8.25 MIPS, and 902 bytes of RAM sufficient for PID-loop math and MODBUS framing. The extended -40C to +125C temperature grade ('E' suffix) handles outdoor and factory-floor thermal stress. Why this part fits: 10-bit on-chip ADC samples 4-20 mA loop signals directly, and 32 KB OTP program memory locks validated control firmware so factory acceptance cannot drift. Design tip: place 100 nF decoupling within 5 mm of every VDD/VSS pair and route the analog AVCC through a ferrite bead to keep ADC noise below 1 LSB.
Recommended
Building Automation Controllers
PIC17C756AT-16E/L is widely deployed in HVAC controllers, lighting panels, and access-control panels where OTP-only firmware and 5V tolerance are acceptable. Its 50 I/O lines handle multiple relay drivers, keypad scanners, and triac interfaces, while the integrated USART talks to BACnet MS/TP or Modbus networks. The 16 MIPS core executes scheduling and PID loops in real time. Why this part fits: 32 KB OTP is enough for HVAC state machines, schedule tables, and fault logging, while the 902-byte RAM holds live setpoints and sensor buffers. Use the capture/compare/PWM to drive triac phase-angle dimming without an extra timer IC.
Recommended
White Goods and Appliance Control
Washing machines, dishwashers, and microwave ovens have used PIC17C756AT-16E/L since the 1990s for motor and user-interface control. The 16 MHz core runs brushless-DC commutation algorithms in real time while the 10-bit ADC reads motor current and temperature sensors. Why this part fits: 32 KB OTP locks in safety-critical motor firmware so firmware cannot be reflashed by unauthorized parties, an asset in appliances that must meet IEC 60335 functional-safety requirements. Design tip: route MCLR through a 10 kohm pull-up and add a 100 nF cap for clean resets during brownout events; connect unused I/O to VDD via 10 kohm to prevent CMOS input latch-up.
Recommended
Automotive Body and Chassis Modules
Automotive body controllers, instrument clusters, and seat modules have shipped with PIC17C756AT-16E/L because its extended -40C to +125C grade matches under-hood and cabin thermal swings. The 50 I/O lines drive bulb and LED arrays, and the USART interfaces with LIN bus slaves. Why this part fits: 32 KB OTP locks validated firmware so it cannot drift during a vehicle's 15-year service life. Note: this part is not AEC-Q100 qualified; for new automotive designs Microchip recommends dsPIC33 or PIC18 K-series parts with AEC-Q100 certification.
Recommended
Instrumentation and Test Equipment Front Panels
PIC17C756AT-16E/L drives keypad scan, LCD multiplex, and GPIB/RS-232 interfaces in legacy bench instruments such as oscilloscopes, signal generators, and power supplies. The 16 MIPS core can refresh a 4-line LCD at 100 Hz while simultaneously scanning a 4x5 keypad matrix with debounce. Why this part fits: 50 I/O lines accommodate the keypad, LCD data bus, status LEDs, and rotary encoder without external mux ICs. 902 bytes RAM is sufficient for command buffers and meter readings. Consider migrating to PIC18F for new designs where in-field firmware updates are required.
Recommended
Motor Drive and PWM Control Front-Ends
PIC17C756AT-16E/L's capture/compare/PWM peripherals generate the timing signals required to drive three-phase inverter modules at 16 MIPS. The 10-bit ADC samples phase currents and DC bus voltage for closed-loop control. Why this part fits: 32 KB OTP locks validated commutation tables and current-loop coefficients; 902 bytes RAM is enough for sensorless BEMF zero-cross detection state. Use the PWM peripheral with dead-band control and route high-current traces away from the crystal oscillator traces to prevent noise injection.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C756AT-16E/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C756A-16I/L | PIC17C756A-16E/PT | PIC17C756A-33E/L | PIC17C752T-33/L | PIC17C756AT-16/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 68-PLCC (L) | 68-PLCC (L) - same | 68-PLCC (L) - same | 68-PLCC (L) - same | 68-PLCC (L) - same | 68-PLCC (L) - same |
| Core Architecture | PIC 8-bit (PIC17C) | PIC 8-bit (PIC17C) - same | PIC 8-bit (PIC17C) - same | PIC 8-bit (PIC17C) - same | PIC 8-bit (PIC17C) - same | PIC 8-bit (PIC17C) - same |
| Maximum Clock | 16 MHz | 16 MHz - same | 16 MHz - same | 33 MHz - higher | 33 MHz - higher | 16 MHz - same |
| Program Memory | 32 KB OTP | 32 KB OTP - same | 32 KB OTP - same | 32 KB OTP - same | 32 KB OTP - same | 32 KB OTP - same |
| RAM | 902 bytes | 902 bytes - same | 902 bytes - same | 902 bytes - same | 678 bytes - lower | 902 bytes - same |
| Operating Temperature | -40C to +125C (E) | -40C to +85C (I) | -40C to +125C (E) - same | -40C to +125C (E) - same | -40C to +85C (I) | -40C to +125C (E) - same |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V - same | 4.5 V to 5.5 V - same | 4.5 V to 5.5 V - same | 4.5 V to 5.5 V - same | 4.5 V to 5.5 V - same |
| Lifecycle Status | NRND (Legacy) | NRND | NRND | NRND | NRND | NRND |
Key Differentiators
- Highest-performance 8-bit PIC before PIC18 era, with 16 MIPS @ 16 MHz and 32 KB OTP (vs PIC16F877A-I/P)
- 68-PLCC J-lead package enables socketed prototyping and field replacement (vs PIC17C756AT-16/PT (64-pin TQFP))
- Extended -40C to +125C industrial temperature grade ('E' suffix) for outdoor and automotive environments (vs PIC17C756A-16I/L (industrial 0-85C))
- OTP program memory locks validated firmware permanently - cannot be reflashed (vs PIC18F6520 Flash MCU)
Design Notes
The PIC17C756AT-16E/L is a 5V-only CMOS MCU operating from 4.5 V to 5.5 V; it has NO on-chip voltage regulator. Place a 100 nF ceramic decoupling capacitor within 5 mm of every VDD/VSS pin pair, and add a 10 uF bulk tantalum or ceramic at the regulator output to handle inrush when ADC and PWM peripherals switch simultaneously. The AVCC/AVSS pins (61/62) should be fed from a separately filtered 5V rail - a 10 ohm resistor + 100 nF cap pi-filter reduces ADC noise by 15-20 dB. Voltage transients above 5.5 V can permanently latch up the CMOS core per the datasheet absolute-maximum ratings.
Route the 16 MHz crystal traces (OSC1/OSC2) on the top layer with a ground guard ring and keep them shorter than 10 mm to minimize EMI. Place the crystal within 5 mm of the OSC pins and never route PWM or relay-drive traces under or alongside the crystal. The MCLR pin should have a 10 kohm pull-up to VDD and a 100 nF cap to ground; if MCLR traces are long, add a TVS diode (e.g., PESD5V0L1BA) for ESD protection. For 68-PLCC socketed designs, route high-speed signals on inner layers and use a continuous ground pour on the top layer to suppress crosstalk.
Do NOT assume PIC17C756AT-16E/L has an internal brown-out reset (BOR); early PIC17C revisions require an external voltage supervisor (e.g., MCP100-475) tied to the MCLR pin for reliable 5V-rail brownouts. The 32 KB OTP program memory cannot be erased - any firmware bug becomes permanent, so always pre-qualify with a windowed PIC17C756A JW part during development before committing to the OTP version. Programming voltage VPP must be 13V with strict rise-time control per the ICSP specification - modern PICkit 4 handles this automatically but legacy programmers may require manual timing.
Compliance Information
RoHS compliance status not explicitly confirmed in verified web data; PIC17C family predates widespread RoHS transition but Microchip has updated most production lines to lead-free. Not AEC-Q100 qualified - for automotive designs use dsPIC33 AEC-Q100 alternatives. Conflict-minerals compliance assumed compliant per Microchip corporate policy.
