PIC17C43-25E/PT - 8-bit 25MHz OTP MCU 8KB | Microchip | TQFP-44
MPN: PIC17C43-25E/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.4 | $164.00 |
| 100 | $14.2 | $1,420.00 |
| 500 | $12.1 | $6,050.00 |
| 1,000 | $10.85 | $10,850.00 |
PIC17C43-25E/PT Overview
An 8-bit microcontroller is a single-chip computer built around an 8-bit data path, ALU, register file, on-chip memory, and integrated peripherals. In the broader taxonomy, it sits under microcontroller -> embedded MCU -> semiconductor IC. The PIC17C4x family is Microchip's mid-1990s high-performance branch, adding a hardware multiplier, multiple interrupt vectors, and a 16-bit-wide instruction word to the classic PIC RISC pipeline for higher throughput than the PIC16C series at the same clock.
Key specifications include a 25 MHz external oscillator, 8 KB OTP program memory, 454 x 8 RAM, 33 I/O lines, and a brown-out-reset / watchdog stack characteristic of the family. The PIC17C43 silicon predates flash; engineers prototype with the EPROM-windowed JW package and produce with the OTP /QTP variants, which is why the -25E/PT part number ends in E (Extended industrial temperature, -40C to +125C).
The architecture combines a Harvard bus, a 16-bit-wide instruction word, and a single-cycle hardware 8 x 8 -> 16-bit multiplier, enabling the 8.25 MIPS throughput at 25 MHz. Peripherals include timers, a USART, Capture/Compare/PWM modules, and an 8-bit ADC on most family members - verify each peripheral against the device data sheet.
Typical applications include industrial control panels, appliance controllers, automotive body modules (pre-CAN), instrumentation front-ends, and legacy embedded systems that were designed around the PIC17C4x ecosystem and remain in production. The extended temperature grade also supports outdoor and automotive under-hood environments.
When designing with this device, note that it is OTP - firmware must be correct on first programming, so emulator or windowed parts are recommended during development. Modern Microchip recommends the PIC18F4220 as the flash-based successor with pin-for-pin migration.
This page synthesizes distributor pricing, drop-in alternatives, and design notes not always present in the manufacturer datasheet.
Drop-in alternatives for PIC17C43-25E/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 PIC17C43-25E/PT (same form factor and footprint) — differing in Package, Program Memory Size, Mounting Type, Maximum Clock Frequency, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C43-25/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C43-33/PT
✅ Drop-In✓ In Stock
$9.3 / Unit
View Datasheet →PIC17C43-33I/PT
✅ Drop-In✓ In Stock
$8.85 / Unit
View Datasheet →PIC17C43-16I/PT
✅ Drop-In✓ In Stock
$5.3 / Unit
View Datasheet →PIC18F4220-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C43-25E/PT Maximum Ratings & Electrical Characteristics
| Architecture | 8-bit PIC17C RISC, Harvard bus |
| Instruction Set Width | 16-bit (single word, 58 instructions) |
| Program Memory Type | OTP (One-Time-Programmable) ROM |
| Program Memory Size | 8 KB (4K x 16 words) |
| RAM Size | 454 x 8 (454 bytes) |
| Maximum Clock Frequency | 25 MHz |
| Performance | 8.25 MIPS (121 ns instruction cycle) |
| Number of I/O Pins | 33 |
| Oscillator Type | External |
| Package | 44-pin TQFP (PT) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +125C (Extended, 'E' suffix) |
| MSL Level | 3 (168 hours) |
| Packaging | Tube |
| RoHS Status | Compliant |
PIC17C43-25E/PT Pin Configuration
| Pin 1 | OSC1 — External oscillator input |
| Pin 2 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / analog input 2 |
| Pin 5 | RA3/AN3 — PORTA bit 3 / analog input 3 |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4 — PORTA bit 5 / analog input 4 |
| Pin 8 | VSS — Ground |
| Pin 9 | OSC2 — External oscillator output / crystal |
| Pin 10 | RC0 — PORTC bit 0 |
| Pin 11 | RC1 — PORTC bit 1 |
| Pin 12 | RC2 — PORTC bit 2 |
| Pin 13 | RC3 — PORTC bit 3 |
| Pin 14 | RD0 — PORTD bit 0 |
| Pin 15 | RD1 — PORTD bit 1 |
| Pin 16 | RD2 — PORTD bit 2 |
| Pin 17 | RD3 — PORTD bit 3 |
| Pin 18 | RC4 — PORTC bit 4 |
| Pin 19 | RC5 — PORTC bit 5 |
| Pin 20 | RC6 — PORTC bit 6 / TX |
| Pin 21 | RC7 — PORTC bit 7 / RX |
| Pin 22 | RB0/INT — PORTB bit 0 / external interrupt |
| Pin 23 | RB1 — PORTB bit 1 |
| Pin 24 | RB2 — PORTB bit 2 |
| Pin 25 | RB3 — PORTB bit 3 |
| Pin 26 | RB4 — PORTB bit 4 |
| Pin 27 | RB5 — PORTB bit 5 |
| Pin 28 | RB6 — PORTB bit 6 |
| Pin 29 | RB7 — PORTB bit 7 |
| Pin 30 | VDD — Positive supply |
| Pin 31 | VSS — Ground |
| 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 | MCLR — Master clear reset (active low) |
| Pin 40 | RA6 — PORTA bit 6 |
| Pin 41 | RA7 — PORTA bit 7 |
| Pin 42 | VSS — Ground |
| Pin 43 | VDD — Positive supply |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC17C43-25E/PT is suitable for 7 applications: Industrial Control Panels, Appliance Controllers, Automotive Body Modules, Test and Measurement Front-Ends, HVAC and Climate Control, Point-of-Sale Terminals, Legacy Embedded Field Replacements.
Industrial Control Panels
The PIC17C43-25E/PT fits industrial control panels because of its 8.25 MIPS throughput, 33 digital I/O lines for buttons and indicators, and Extended -40C to +125C temperature grade. At 25 MHz the part scans a 32-key matrix in well under 1 ms while leaving headroom for PID loops driving relays. The OTP memory means firmware must be locked at production, which is acceptable for high-volume panel runs.
Recommended
Appliance Controllers
White-goods and small-appliance controllers benefit from the PIC17C43-25E/PT's small TQFP-44 footprint, low cost at high volume, and 58-instruction PIC17C4x RISC core that compiles efficiently to handle motor timing and sensor reading. The 8 KB OTP holds a full wash-cycle state machine plus UI driver, while 33 I/O pins cover triac drives, LEDs, and keypad rows without external expanders.
Recommended
Automotive Body Modules
Body-electronics modules from the late 1990s and early 2000s commonly used the PIC17C43-25E/PT family for seat controllers, mirror drivers, and lighting nodes. The Extended -40C to +125C grade handles under-hood thermal stress, and the 25 MHz core runs LIN slave stacks and PWM dimming simultaneously. Designers porting these legacy modules to modern platforms should evaluate PIC18F4220 for new builds.
Recommended
Test and Measurement Front-Ends
Bench instruments and panel meters leverage the PIC17C43-25E/PT's 8.25 MIPS to scan multiplexed ADCs and drive character LCDs in real time. The Harvard bus and 16-bit instructions keep interrupt latency deterministic for front-panel keypads, while 454 bytes of RAM comfortably buffer measurement strings. The 33 I/O lines support both parallel LCDs and SPI/I2C sensor chains without external logic.
Recommended
HVAC and Climate Control
HVAC controllers use the PIC17C43-25E/PT to read thermistor and pressure sensors, drive triac-controlled fan stages, and manage a character LCD. Its Extended temperature grade survives plenum environments, and the 16-bit instruction word fits a real-time scheduler in fewer cycles than PIC16C alternatives. Legacy HVAC firmware can be preserved by retaining the OTP part rather than migrating to flash.
Recommended
Point-of-Sale Terminals
Older point-of-sale terminals and EFT-PIN pads used PIC17C43-class parts for keyboard handling, display refresh, and cryptographic co-processor glue logic. The Extended temperature range and 33 I/O pins accommodate keypad matrix, character display, magnetic-stripe interface, and serial smart-card channel. OTP memory is a security advantage in payment terminals because firmware cannot be rewritten via external attacks.
Recommended
Legacy Embedded Field Replacements
Industrial installations from the late 1990s still run PIC17C43-25E/PT firmware in pumps, controllers, and remote telemetry units where the OTP requirement was never a drawback. Field replacement boards must use the same TQFP-44 footprint, and the PIC17C43 family variants are listed on Microchip's longevity program for sustained supply. Engineers replacing failed boards should match the -E temperature suffix and verify the existing firmware binary ID before swap.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C43-25E/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C43-25/PT | PIC17C43-33/PT | PIC17C43-16I/PT | PIC18F4220-I/PT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | TQFP-44 (PT) | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same |
| Program Memory | 8 KB OTP | 8 KB OTP | 8 KB OTP | 8 KB OTP | 16 KB Flash (reprogrammable) |
| Maximum Clock | 25 MHz | 25 MHz | 33 MHz | 16 MHz | 40 MHz |
| Throughput | 8.25 MIPS | 8.25 MIPS | 10.9 MIPS | 5.3 MIPS | 10 MIPS |
| Temperature Grade | Extended -40C to +125C | Commercial 0C to +70C | Commercial 0C to +70C | Industrial -40C to +85C | Industrial -40C to +85C |
| Memory Type | OTP ROM (one-time) | OTP ROM | OTP ROM | OTP ROM | Flash (reprogrammable) |
| Lifecycle Status | NRND | NRND | NRND | NRND | Active |
Key Differentiators
- Extended -40C to +125C temperature grade vs commercial siblings (vs PIC17C43-25/PT)
- Mature PIC17C4x instruction set with 58 single-word instructions (vs PIC18F4220-I/PT)
- OTP memory for tamper-resistant firmware (vs PIC18F4220-I/PT)
Design Notes
The PIC17C43-25E/PT uses One-Time-Programmable memory - the bitcell cannot be erased after programming, so any firmware bug locked into the silicon is permanent. Always validate firmware on a windowed JW package or PIC17C4x emulator before committing to OTP production parts. Budget for OTP programming time and one-time tooling cost when targeting this part for a new design.
At the maximum 25 MHz clock and 5V supply, the PIC17C43-25E/PT draws roughly 50 mA, dissipating 250 mW. Estimated junction temperature rise with the standard TQFP-44 PCB footprint and no airflow is about 25C above ambient assuming a JEDEC-standard 4-layer test board - well within the 125C maximum. In enclosed industrial cabinets, derate clock frequency or add minimal airflow to maintain margin.
Place the external crystal or resonator within 10 mm of the OSC1/OSC2 pins and keep the trace pair short and symmetrical to avoid clock distortion. Decouple VDD with a 100 nF ceramic placed as close as possible to each VDD pin, and add a bulk 10 uF tantalum near the package. MCLR must have a 10 kohm pull-up to VDD and a 100 nF capacitor to ground for clean reset behavior.
TQFP-44 is a fine-pitch (0.8 mm) package - use JEDEC MS-026 land patterns and 4 mil trace-and-space rules. Stencil-aperture reduction to 80% on thermal pads and 90% on perimeter pads helps prevent solder bridging on production runs. Reflow profile should follow JEDEC J-STD-020 with peak temperature no greater than 250C for the matte-tin lead finish.
Compliance Information
RoHS and lead-free per Microchip product page. Not AEC-Q100 qualified - parts marked 'E' indicate Extended temperature only, not automotive qualification. For AEC-Q100 requirements consider PIC18F variants explicitly qualified by Microchip.