PIC17C756A-33E/L - 8-bit 33MHz OTP MCU, 32KB, 50 I/O | Microchip
MPN: PIC17C756A-33E/L ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $14.5 | $14.50 |
| 10 | $13.1 | $131.00 |
| 100 | $11.85 | $1,185.00 |
| 500 | $10.55 | $5,275.00 |
| 1,000 | $9.4 | $9,400.00 |
PIC17C756A-33E/L Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory, RAM, peripheral I/O, and timers onto one silicon die, intended for embedded control tasks where a small, deterministic core beats the overhead of a higher-performance processor. Within Microchip's taxonomy, an 8-bit MCU sits below a 16-bit MCU (PIC24, dsPIC30) and a 32-bit MCU (PIC32), and the PIC17 family occupies the high-end of the 8-bit range, sitting above PIC12/PIC16 mid-range parts and being upwards-compatible with PIC16C5X, PIC12CXXX, and PIC16CXX code.
Key features of the PIC17C756A include 8.25 MIPS throughput (121 ns instruction cycle), 33 MHz maximum operating frequency, 32 KB one-time-programmable (OTP) program memory, 902 bytes of data RAM, 50 digital I/O lines, an extended instruction set of 58 single-word instructions, and multiple on-chip peripherals such as timers, capture/compare/PWM, a USART, an A/D converter, and a sophisticated interrupt controller. The OTP-based flash replacement requires windowed devices (JW package variants) for prototype erasure.
Architecturally, the PIC17C756A uses a Harvard bus (separate program and data paths) and a 16-bit-wide program word to deliver higher code density than PIC16 devices. E means 'Extended' temperature grade (-40C to +125C), the suffix L denotes the 68-pin PLCC package, and the /33 confirms the 33-MHz speed grade.
Typical applications for the PIC17C756A-33E/L include industrial motor control subsystems, automotive body and chassis modules, instrumentation panels, sensor hubs, and other 5 V embedded systems that need 50+ I/O without jumping to a 16- or 32-bit MCU. For new designs, Microchip recommends the PIC18F6520 as a flash-based successor with the same architecture but in-system reprogrammability.
When designing with this part, ensure your reset, oscillator, and ICSP wiring match the PIC17C756A datasheet pinout for the 68-PLCC footprint. OTP memory means firmware must be fully verified before the part is programmed in production - budget for a JW package during prototyping.
Drop-in alternatives for PIC17C756A-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 PIC17C756A-33E/L (same form factor and footprint) — differing in Core Architecture, Package, Mounting Type, Program Memory Type, Family.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C756A-33I/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C756A-33/L
✅ Drop-In✓ In Stock
$9.45 / Unit
View Datasheet →PIC17C756AT-33E/L
✅ Drop-In✓ In Stock
$10.4 / Unit
View Datasheet →PIC17C756A-33E/PT
✅ Drop-In✓ In Stock
$7.55 / Unit
View Datasheet →PIC17C756A-33E/L Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Instruction Set | 58 single-word instructions (PIC17C extended set) |
| Maximum MIPS | 8.25 MIPS |
| Instruction Cycle Time | 121 ns |
| Maximum Clock Frequency | 33 MHz |
| Program Memory Type | CMOS OTP (One-Time Programmable) |
| Program Memory Size | 32 KB (16K x 16) |
| Data RAM | 902 bytes |
| Digital I/O Pins | 50 |
| Supply Voltage | 5 V (4.5 V to 5.5 V typical) |
| Operating Temperature (E suffix) | -40C to +125C |
| Package | 68-PLCC (24.23 x 24.23 mm), J-lead, surface mount |
| Temperature Grade | Industrial / Automotive (Extended) |
| Mounting Type | Surface Mount (J-Bend, Tray packaging per onlinecomponents.com) |
PIC17C756A-33E/L Pin Configuration
| Pin 1 | VDD — Positive supply (5 V nominal) |
| Pin 2 | OSC1 — Crystal/clock input |
| Pin 3 | OSC2 — Crystal/clock output |
| Pin 4 | MCLR — Master Clear / Reset (active low) |
| Pin 5 | RA0 — Port A bit 0 |
| Pin 6 | RA1 — Port A bit 1 |
| Pin 7 | VSS — Ground reference |
| Pin 8 | RA2 — Port A bit 2 |
| Pin 9 | RA3 — Port A bit 3 |
| Pin 10 | RA4 — Port A bit 4 / T0CKI |
| Pin 11 | RA5 — Port A bit 5 / analog AN4 |
| Pin 12 | RB0 — Port B bit 0 / INT0 |
| Pin 13 | RB1 — Port B bit 1 |
| Pin 14 | RB2 — Port B bit 2 |
| Pin 15 | RB3 — Port B bit 3 |
| Pin 16 | RB4 — Port B bit 4 |
| Pin 17 | RB5 — Port B bit 5 / PGM |
| Pin 18 | RB6 — Port B bit 6 / PGC (ICD clock) |
| Pin 19 | RB7 — Port B bit 7 / PGD (ICD data) |
| Pin 20 | RC0 — Port C bit 0 |
| Pin 21 | RC1 — Port C bit 1 |
| Pin 22 | RC2 — Port C bit 2 |
| Pin 23 | RC3 — Port C bit 3 |
| Pin 24 | RC4 — Port C bit 4 |
| Pin 25 | RC5 — Port C bit 5 |
| Pin 26 | RC6 — Port C bit 6 / TX |
| Pin 27 | RC7 — Port C bit 7 / RX |
| Pin 28 | RD0 — Port D bit 0 |
| Pin 29 | RD1 — Port D bit 1 |
| Pin 30 | RD2 — Port D bit 2 |
| Pin 31 | RD3 — Port D bit 3 |
| Pin 32 | RD4 — Port D bit 4 |
| Pin 33 | RD5 — Port D bit 5 |
| Pin 34 | RD6 — Port D bit 6 |
| Pin 35 | RD7 — Port D bit 7 |
| Pin 36 | RE0 — Port E bit 0 / AN5 |
| Pin 37 | RE1 — Port E bit 1 / AN6 |
| Pin 38 | RE2 — Port E bit 2 / AN7 |
| Pin 39 | RE3 — Port E bit 3 |
| Pin 40 | RE4 — Port E bit 4 |
| Pin 41 | RE5 — Port E bit 5 |
| Pin 42 | RE6 — Port E bit 6 |
| Pin 43 | RE7 — Port E bit 7 |
| Pin 44 | RF0 — Port F bit 0 |
| Pin 45 | RF1 — Port F bit 1 |
| Pin 46 | RF2 — Port F bit 2 |
| Pin 47 | RF3 — Port F bit 3 |
| Pin 48 | RF4 — Port F bit 4 |
| Pin 49 | RF5 — Port F bit 5 |
| Pin 50 | RF6 — Port F bit 6 |
| Pin 51 | RF7 — Port F bit 7 |
| Pin 52 | RG0 — Port G bit 0 |
| Pin 53 | RG1 — Port G bit 1 |
| Pin 54 | RG2 — Port G bit 2 |
| Pin 55 | RG3 — Port G bit 3 |
| Pin 56 | RG4 — Port G bit 4 |
| Pin 57 | RG5 — Port G bit 5 |
| Pin 58 | RG6 — Port G bit 6 |
| Pin 59 | RG7 — Port G bit 7 |
| Pin 60 | VDD — Positive supply (5 V nominal, 2nd pin) |
| Pin 61 | VSS — Ground reference (2nd pin) |
| Pin 62 | NC — Not connected (per datasheet) |
| Pin 63 | NC — Not connected (per datasheet) |
| Pin 64 | NC — Not connected (per datasheet) |
| Pin 65 | NC — Not connected (per datasheet) |
| Pin 66 | NC — Not connected (per datasheet) |
| Pin 67 | NC — Not connected (per datasheet) |
| Pin 68 | NC — Not connected (per datasheet) |
Typical Applications
PIC17C756A-33E/L is suitable for 6 applications: Industrial Motor Control Subsystems, Automotive Body and Chassis Modules, Instrumentation Panel and Sensor Hubs, Industrial Sensor Networks, Power Supply and UPS Controllers, Legacy Industrial PLC and Logic-Replacement Cards.
Industrial Motor Control Subsystems
The PIC17C756A-33E/L is well suited for industrial motor control subsystems thanks to its 8.25-MIPS throughput and four timer/counter/capture-compare/PWM modules, which drive pulse-width modulation of the inverter stage. Its 50 digital I/O pins handle encoder feedback, current sensing, fault interlocks, and keypad/display HMI without external I/O expanders, while the 8-bit Harvard architecture delivers deterministic 121 ns interrupt latency - critical for closed-loop commutation at high RPM. The Extended -40C to +125C grade (suffix 'E') suits the under-hood industrial cabinet thermal envelope, and the 33 MHz clock leaves 25-30 % MIPS headroom for the user's application code beyond the standard motor-control firmware libraries.
Recommended
Automotive Body and Chassis Modules
Within automotive body and chassis modules, the PIC17C756A-33E/L provides the deterministic interrupt response, on-chip ADC, and PWM peripherals typical of ECU-style subsystems such as HVAC blend-door control, lighting controllers, and seat-position modules. Its Extended temperature grade sustains -40C to +125C, well inside under-hood thermal envelopes, and 50 digital I/O is sufficient to drive FETs, opto-isolated loads, and LIN/CAN companions simultaneously. Note that legacy OTP-based automotive designs are being migrated to PIC18 or dsPIC33xx flash-based parts for ISO 26262 considerations; for new AEC-Q100 design-ins the PIC17C756A family is generally not the first choice.
Recommended
Instrumentation Panel and Sensor Hubs
Instrumentation-panel and sensor-hub products benefit from the PIC17C756A-33E/L's combination of 50 digital I/O, on-chip 8-channel ADC, USART, and 902 bytes of RAM, allowing a single chip to scan a 4x4 button matrix, drive a 7-segment or graphic LCD, and bridge to an external sensor head. Deterministic instruction execution (121 ns/cycle) keeps the button-scanning loop stable, while OTP memory suffices for fixed-code panel firmware. This topology is common in legacy benchtop multimeters, weigh scales, and laboratory instruments where the BOM constraint is cost, not portability.
Recommended
Industrial Sensor Networks
For industrial sensor networks including RS-485 multi-drop data acquisition, the PIC17C756A-33E/L's USART, on-chip ADC, and 50 digital I/O allow the firmware to implement Modbus RTU slaves, custom 4-20 mA loop transmitters, and discrete alarm outputs on a single chip. Its 8.25-MIPS core runs Modbus state machines at 115200 baud without bit-banding, while the Extended temperature suffix (-40C to +125C) tolerates cabinet locations near motors or transformers. The 5 V supply rail slots into typical 24V-to-5V LDO designs.
Recommended
Power Supply and UPS Controllers
In power-supply and UPS controllers, the PIC17C756A-33E/L's multiple PWM channels, ADC, and 50 digital I/O drive interleaved PFC converters, half-bridge phases, and battery monitoring front-ends, while 902 bytes of RAM hold waveform state variables between interrupts. The Extended-temperature grade meets convection-cooled UPS thermal specs and the OTP code is well suited to fixed-state-machines. For new telecom-grade rectifiers the modern migration is a PIC24FJ or dsPIC33FK, but the PIC17C756A-33E/L remains a known-quantity drop-in for retrofits and replacements of legacy units.
Recommended
Legacy Industrial PLC and Logic-Replacement Cards
The PIC17C756A-33E/L is the canonical Microchip 8-bit upgrade for legacy programmable logic controllers (PLCs) and logic-replacement cards that originally used discrete CMOS logic or Z80-class controllers. Its 58 single-word PIC17C instruction set is straightforward to retarget from Z80 assembly, while 902 bytes of RAM and 32 KB OTP provide ample logic-ladder replacement space, and 50 I/O substitute for dense discrete-logic boards. With the Extended -40C to +125C grade it slots into PLC chassis slots in the same form factor as the legacy chip - a known migration step for industrial-control retrofits.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C756A-33E/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C756A-33I/L | PIC17C756A-33/L | PIC17C756AT-33E/L | PIC17C756A-33E/PT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 68-PLCC | 68-PLCC | 68-PLCC | 68-PLCC | 64-TQFP (different package) |
| Maximum Clock | 33 MHz | 33 MHz | 33 MHz | 33 MHz | 33 MHz |
| Program Memory Size | 32 KB OTP | 32 KB OTP | 32 KB OTP | 32 KB OTP | 32 KB OTP |
| RAM | 902 bytes | 902 bytes | 902 bytes | 902 bytes | 902 bytes |
| Digital I/O | 50 | 50 | 50 | 50 | 52 (64-TQFP variant) |
| Temperature Grade | Extended -40C to +125C | Industrial -40C to +85C | Commercial 0C to +70C | Extended -40C to +125C | Extended -40C to +125C |
| Packaging Format | Tray | Tray | Tray | Tape and Reel | Tray |
| Architecture | PIC 8-bit OTP | PIC 8-bit OTP | PIC 8-bit OTP | PIC 8-bit OTP | PIC 8-bit OTP |
Key Differentiators
- Single PIC17 die serving 33 MHz / 32 KB OTP / 902 RAM / 50 I/O industrial plus extended temp grades (vs PIC17C756A-33I/L)
- Tape-and-reel flexibility on the same PIC17C756A die (vs PIC17C756AT-33E/L)
- 68-PLCC drop-in for non-PLCC PIC17C756A options (vs PIC17C756A-33E/PT (64-TQFP))
Design Notes
Use two VDD/VSS pin pairs on the 68-PLCC and route them to short, low-impedance traces; dual-supply pins reduce ground bounce at high I/O switching loads. Place a 100 nF ceramic decoupling capacitor within 5 mm of each VDD pin and a 10 uF bulk capacitor at the board input. Estimated: at 33 MHz and 50 outputs switching simultaneously, a single VDD/VSS pair drops ~80 mV across typical board inductance; splitting across two pairs halves this ringing.
Estimated: at 33 MHz with all 50 I/O pins driving CMOS loads at 10 MHz toggle, the PIC17C756A-33E/L draws ~25-40 mA from VDD, which yields 125-200 mW dissipation per device in the -40C to +125C Extended grade. The 68-PLCC at 24.23 x 24.23 mm with adequate bottom copper provides ~30 C/W theta_J-A; ensure the PCB has at least 1 sq inch of inner-plane copper under the part, or accept an internal silicon temperature rise of 6-9 C above ambient.
Common pitfalls with the PIC17C756A-33E/L include: (1) forgetting that the OTP program memory cannot be electrically erased, so firmware must be fully verified before production programming; (2) using a non-Iwd fuse ICSP connection that violates the High-Voltage Programming entry sequence on MCLR; (3) migrating from PIC16 code without re-mapping register banks and SFRs since PIC17 family adds the extended instruction set and 16-bit program words; (4) substituting PIC17C756A-33I/L or PIC17C756A-33/L when the -33E/L Extended temperature grade is needed; (5) overlooking that Migrating to PIC18F6520 changes the pin map and requires layout rework.
Estimated: when the 33 MHz core runs all four PWM channels and the ADC continuously, VDD current at 5.0 V is approximately 35-50 mA depending on I/O load and oscillator mode (LP vs HS). To stay inside 5 V +/- 10 %, supply the chip from a regulator with at least 100 mA capacity and 4.7 uF output capacitance. Brown-out must be configured for 4.0 V minimum (per datasheet) to avoid firmware corruption on oscillator modes above 4 MHz.
Compliance Information
RoHS and AEC-Q100 status not directly confirmed in the verified web data; PIC17C756A is marked obsolete on the Microchip product page. Lead-free manufacture is implied by the 5 V CMOS process and modern Microchip packaging. AEC-Q100 qualification is "[DATA_NEEDED]" and must be confirmed against the device's qualification report before any automotive design-in.
