PIC17C43T-25I/PT - 8-bit OTP MCU 8KB EPROM 25MHz TQFP-44 | Microchip
MPN: PIC17C43T-25I/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $11.95 | $11.95 |
| 10 | $10.75 | $107.50 |
| 100 | $9.55 | $955.00 |
| 500 | $8.62 | $4,310.00 |
| 1,000 | $7.74 | $7,740.00 |
PIC17C43T-25I/PT Overview
An 8-bit microcontroller (MCU) is a self-contained computing element built around an 8-bit data path, on-chip program memory, on-chip data RAM, and a set of peripherals such as timers, capture/compare/PWM modules, USARTs, and I/O ports. The PIC17C43 sits at the top of the original PIC17C family - a high-performance extension of the PIC16 mid-range line - and was Microchip's first PIC architecture to feature a 16-bit instruction word with 8-bit data, hardware multiply, multiple interrupt sources, and a 16-level hardware stack. It belongs to the broader hierarchy: microcontroller -> embedded controller -> semiconductor -> integrated circuit.
Key differentiating features include only 58 single-word instructions to learn (simplifying firmware development), a 25 MHz external clock input yielding a 160 ns instruction cycle, an instruction set with hardware multiply, four interrupt sources, a 16-level deep hardware stack, and 33 I/O pins (in the 44-pin TQFP). The architecture also incorporates a 4x phase-locked loop option on some family members, hardware USART, multiple timer/counter blocks, and capture/compare/PWM modules suited to real-time embedded control.
The PIC17C43 is built on a CMOS EPROM process, allowing prototype and low-volume production programming with a windowed or OTP package. Industrial-temperature silicon ensures operation across -40 C to +85 C. Typical applications include industrial automation controllers, motor-control front-ends, instrumentation, automotive body and chassis modules (non-safety), embedded data-acquisition front-ends, and legacy embedded control designs that must be maintained or replaced part-for-part during long-lifecycle product support. Microchip recommends the newer PIC18F4220 as a modern migration path for new designs.
When designing with this part, treat the OTP window carefully: the PIC17C43T ships as one-time-programmable, so code must be fully verified before production programming. Use the 44-pin TQFP land pattern exactly as published by Microchip, allow bulk decoupling near VDD/VSS pairs, and ensure the oscillator load capacitors match the chosen crystal. For new designs, evaluate the PIC18F family first; for legacy board repairs, the PIC17C43T-25I/PT remains a direct, footprint-compatible option.
Drop-in alternatives for PIC17C43T-25I/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 PIC17C43T-25I/PT (same form factor and footprint) — differing in Package, Program Memory Type, Instruction Cycle Time, Timers, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C43T-25I/PQ
✅ Drop-In✓ In Stock
$13.5 / Unit
View Datasheet →PIC17C43T-25E/PT
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$10.65 / Unit
View Datasheet →PIC17C43T-25/PQ
✅ Drop-In✓ In Stock
$8.1 / Unit
View Datasheet →PIC17C43T-16/PT
✅ Drop-In✓ In Stock
$8.7 / Unit
View Datasheet →PIC17C43-25E/PT
✅ Drop-In✓ In Stock
$10.85 / Unit
View Datasheet →PIC17C43-16I/PT
✅ Drop-In✓ In Stock
$5.3 / Unit
View Datasheet →PIC17C43T-25I/PT Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit Microcontroller (MCU) |
| Architecture | PIC17C (Harvard, 16-bit instruction / 8-bit data) |
| Program Memory | 8 KB OTP EPROM |
| Data RAM | 454 bytes |
| Maximum Clock Frequency | 25 MHz |
| Instruction Cycle Time | 160 ns at 25 MHz (121 ns at 33 MHz family max) |
| Instruction Set Size | 58 single-word instructions |
| I/O Pins | 33 |
| Hardware Stack | 16-level deep |
| Package | TQFP-44 (PT), 10x10 mm, 0.8 mm pitch |
| Operating Temperature Range | -40 C to +85 C (Industrial, 'I' suffix) |
| Packaging Form | Tape and Reel (T suffix) |
| Mounting Type | Surface Mount |
| RoHS Status | unknown |
| Program Memory Type | OTP EPROM (one-time-programmable) |
PIC17C43T-25I/PT Pin Configuration
| Pin 1 | OSC1 — Crystal/Resonator oscillator input |
| Pin 2 | OSC2 — Crystal/Resonator oscillator output |
| Pin 3 | MCLR — Master Clear (Reset) input, 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, T0CKI) |
| Pin 9 | RA5 — Port A bit 5 (digital I/O) |
| Pin 10 | VSS — Ground reference |
| Pin 11 | VDD — Positive supply voltage (+5 V nominal) |
| Pin 12 | RB0 — Port B bit 0 (digital I/O, INT0) |
| 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 reference |
| Pin 21 | VDD — Positive supply voltage (+5 V nominal) |
| Pin 22 | RC0 — Port C bit 0 (digital I/O) |
| Pin 23 | RC1 — Port C bit 1 (digital I/O, T1CKI) |
| Pin 24 | RC2 — Port C bit 2 (digital I/O, CCP1) |
| 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/CK) |
| Pin 29 | RC7 — Port C bit 7 (digital I/O, RX/DT) |
| 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 reference |
| Pin 39 | VDD — Positive supply voltage (+5 V nominal) |
| Pin 40 | RE0 — Port E bit 0 (digital I/O, AN5/RD-bar) |
| Pin 41 | RE1 — Port E bit 1 (digital I/O, AN6/WR-bar) |
| Pin 42 | RE2 — Port E bit 2 (digital I/O, AN7/CS-bar) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC17C43T-25I/PT is suitable for 6 applications: Industrial Automation Controllers, Motor Control and PWM Drive Front-Ends, Embedded Instrumentation and Data Acquisition, Automotive Body and Chassis Modules (Non-Safety), Legacy Embedded Control Field Replacement, Security and Access-Control Panels.
Industrial Automation Controllers
The PIC17C43T-25I/PT suits industrial automation controllers because its 8 KB of OTP program memory holds substantial state-machine and ladder-logic firmware while the 454 bytes of RAM cover real-time I/O buffering and inter-task messaging. Its 25 MHz clock yields a 160 ns instruction cycle, letting the part execute deterministic PID loops, encoder decoding, and serial-protocol servicing inside tight scan budgets. The 33 digital I/O pins support mixed sensor-actuator wiring without external expanders, and the industrial -40 C to +85 C range tolerates factory-floor enclosures. Compared with PIC16 mid-range parts, the 58-instruction PIC17C core and 16-level hardware stack give this MCU the headroom needed for larger control applications.
Recommended
Motor Control and PWM Drive Front-Ends
The PIC17C43T-25I/PT serves as a PWM and trapezoidal/sine commutation front-end for small brushless-DC and stepper motor drives. Its on-chip capture/compare/PWM modules generate multiple synchronized PWM channels at the 25 MHz clock rate, and the 160 ns instruction cycle keeps control-loop latency below the typical 10 us commutation period. The Harvard architecture avoids instruction-fetch stalls during tight control loops, and the 33 I/O pins handle Hall sensors, encoder feedback, fault inputs, and gate-driver enables simultaneously. Engineers migrating from PIC17C43 designs use the part for legacy equipment service where firmware portability outweighs the appeal of newer PIC18F devices.
Recommended
Embedded Instrumentation and Data Acquisition
Laboratory instruments and bench-top data-acquisition front-ends benefit from the PIC17C43T-25I/PT because the 8 KB OTP program memory stores full calibration tables and command parsers while the 25 MIPS-class throughput handles real-time averaging, peak detection, and serial reporting. The Harvard PIC17C core allows deterministic ADC servicing with no interrupt jitter from bus contention, and the 33 I/O pins connect to keypads, LCD interfaces, and front-panel LEDs without external logic. The industrial temperature grade lets the part sit inside laboratory chassis that vary with ventilation airflow. Service teams value the part because it remains pin-compatible across PIC17C42A and PIC17C44 family members for board-level repair.
Recommended
Automotive Body and Chassis Modules (Non-Safety)
The PIC17C43T-25I/PT appears in older automotive body controllers for lighting, wipers, seat controls, and HVAC actuators where the industrial -40 C to +85 C grade suffices and the 5 V VDD matches existing harness designs. The Harvard 8-bit core keeps timing deterministic for CAN/LIN-style bit-banged protocols in vehicles without on-chip CAN, and the 8 KB OTP accommodates seat-position memory maps plus diagnostics. Engineers maintaining 1990s and early-2000s vehicles source this NRND part for end-of-life repairs. New automotive designs must migrate to AEC-Q100-qualified dsPIC33 or PIC18 K-series parts; the PIC17C43T-25I/PT is not AEC-Q100 qualified and should not be specified for new safety-critical automotive systems.
Recommended
Legacy Embedded Control Field Replacement
The PIC17C43T-25I/PT is a primary source for field replacement of legacy PIC17C-based boards that must remain operational for decades - industrial PLCs, building-automation nodes, HVAC controllers, and aerospace ground-support equipment. Its 8 KB OTP and 25 MHz throughput match the original firmware that customers cannot re-validate. Because the part is NRND, repair depots stock this exact MPN plus its /PQ and -25E variants to cover both TQFP and MQFP boards and both industrial and extended temperature designs. The wide second-source availability through distributors like Ample-Chip, Veswin, and OMO Electronic supports long-tail service programs.
Recommended
Security and Access-Control Panels
Access-control panels, alarm keypads, and intrusion-detection systems use the PIC17C43T-25I/PT because its 58-instruction PIC17C core provides fast keypad scanning and lock-driver control while the 8 KB OTP stores user credentials and event logs. The 33 I/O pins handle matrix keypads, multi-zone status LEDs, buzzer drivers, and Wiegand reader interfaces without external logic. The industrial temperature grade tolerates vestibule and parking-garage enclosures. For new security designs, Microchip's PIC18F family adds crypto accelerators and secure firmware update, but legacy panels continue to ship with the PIC17C43T-25I/PT for backward compatibility with installed bases.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C43T-25I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C43T-25I/PQ | PIC17C43T-25E/PT | PIC17C43T-25/PQ | PIC17C43T-16/PT | PIC17C43-25E/PT | PIC17C43-16I/PT |
|---|---|---|---|---|---|---|---|
| Package | TQFP-44 (PT) | MQFP-44 (PQ) - same footprint pattern, different lead form | TQFP-44 (PT) - identical | MQFP-44 (PQ) - different lead form | TQFP-44 (PT) - identical | TQFP-44 (PT) - identical | TQFP-44 (PT) - identical |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Frequency | 25 MHz | 25 MHz | 25 MHz | 25 MHz | 16 MHz | 25 MHz | 16 MHz |
| Program Memory | 8 KB OTP | 8 KB OTP | 8 KB OTP | 8 KB OTP | 8 KB OTP | 8 KB OTP | 8 KB OTP |
| Data RAM | 454 bytes | 454 bytes | 454 bytes | 454 bytes | 454 bytes | 454 bytes | 454 bytes |
| Instruction Cycle | 160 ns | 160 ns | 160 ns | 160 ns | 250 ns | 160 ns | 250 ns |
| Temperature Grade | Industrial -40 C to +85 C | Industrial -40 C to +85 C | Extended -40 C to +125 C | Commercial 0 C to +70 C | Industrial -40 C to +85 C | Extended -40 C to +125 C | Industrial -40 C to +85 C |
| Packaging Form | Tape and Reel | Tape and Reel | Tape and Reel | Tape and Reel | Tape and Reel | Tray | Tray |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 | 33 |
Key Differentiators
- Highest 25 MHz speed grade in a Microchip TQFP-44 PIC17C footprint (vs PIC17C43T-16/PT)
- Industrial -40 C to +85 C temperature grade (vs PIC17C43T-25/PQ)
- Tape-and-reel packaging ready for SMT lines (vs PIC17C43-25E/PT)
- Same die and footprint as extended-temperature PIC17C43T-25E/PT (vs PIC17C43T-25E/PT)
Design Notes
The PIC17C43T-25I/PT operates from a single 5 V nominal VDD rail. Place a 100 nF decoupling capacitor as close as possible to each VDD/VSS pin pair (the 44-pin TQFP has multiple VDD/VSS pins) and add a bulk 10 uF tantalum or ceramic cap at the board's VDD entry point. For battery-backed designs, the MCLR/VPP pin can be tied to VDD through a 10 kohm resistor with a diode clamp to protect against in-circuit programming transients.
Keep the crystal oscillator traces (OSC1/OSC2) short and surrounded by a ground guard ring to minimize EMI pickup. The TQFP-44 land pattern uses 0.8 mm pitch pads; design the PCB with a 4-layer stack-up and dedicate one inner plane to ground to reduce noise coupling onto the analog-capable pins on Port E. Leave the two NC pads (pins 43 and 44 per the pinout table) floating or grounded per board layout convention - they do not connect internally to the silicon.
Because the PIC17C43T-25I/PT is OTP EPROM, firmware bugs cannot be field-patched - fully verify code on a windowed PIC17C43JW or flash-based PIC18F452 prototype before committing to production programming. Do not confuse the /PT (TQFP-44) suffix with the /PQ (MQFP-44) suffix; the packages have different lead forms and footprints and cannot be interchanged without PCB rework. The part is NRND, so for new designs plan a migration path to the PIC18F family, and qualify second-source PIC17C43-16I/PT variants for slow-throughput legacy support.
Compliance Information
Compliance status was not present in the verified web data for this NRND part. PIC17C43T-25I/PT is NOT AEC-Q100 qualified and must not be specified for new automotive safety-critical designs. For automotive applications use AEC-Q100-qualified dsPIC33 or PIC18 K-series parts.
