PIC17C44T-25I/PQ - 8-bit 25MHz OTP MCU 16KB | Microchip
MPN: PIC17C44T-25I/PQ ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $13.5 | $13.50 |
| 10 | $12.15 | $121.50 |
| 100 | $10.85 | $1,085.00 |
| 500 | $9.55 | $4,775.00 |
| 1,000 | $8.45 | $8,450.00 |
PIC17C44T-25I/PQ Overview
An OTP (One-Time Programmable) microcontroller is a programmable device whose on-chip program memory is a one-time-writable EPROM cell - the device can be programmed once by the user before being sealed, after which the program is permanent. The PIC17C family sits above the PIC16C in the Microchip 8-bit hierarchy (PIC10F -> PIC12F -> PIC16F -> PIC17C -> PIC18F), offering higher throughput and expanded peripheral integration for cost-sensitive embedded applications that need more MIPS than a PIC16C but less complexity than a 16-bit dsPIC.
Key features include 58 single-word instructions, a single-cycle instruction execution architecture (121 ns at 25 MHz oscillator), an operating voltage of 5V, 33 digital I/O lines, and a 25 MHz maximum clock input with up to 33 MHz clock tolerance. The device supports up to 16 KB of EPROM program memory with 454 x 8 bytes of data RAM, and the 44-pin MQFP (PQ) package provides generous I/O count and a compact surface-mount footprint for industrial-grade (-40C to +85C) operation.
Architecturally, the PIC17C44 uses Microchip's RISC-based PIC core with a 16-bit instruction word and 8-bit data path, an internal 16-level hardware stack for fast subroutine calls, and a Harvard bus structure that separates program and data fetches to enable single-cycle instruction throughput. Industrial-temperature screening (the "I" suffix) and the EPROM-based OTP cell make this part well suited to legacy embedded control designs that need one-time-coded firmware and long-life supply continuity.
Typical applications include industrial automation controllers, motor control front-ends, embedded instrumentation, legacy control board retrofits, and white-goods appliance control. The 33 I/O count supports keypad scanning, LED/LCD multiplexing, and direct drive of relays, solenoids, and small stepper motors. Engineers familiar with PIC16C migration paths often choose PIC17C44 because the instruction set is upward-compatible while offering roughly twice the throughput.
When designing with this device, plan for an external 5V regulator, decoupling caps on VDD/AVDD pairs, and a programmer that supports EPROM OTP (e.g., MPLAB PM3). Note that the PIC17C44 is a mature EOL/EOL-near part - confirm long-term availability before committing to new designs, and consider the modern PIC18F442 or PIC18F452 as pin-compatible successors.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC17C44T-25I/PQ — 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 PIC17C44T-25I/PQ (same form factor and footprint) — differing in Package, Core, Maximum Clock Frequency, Program Memory Size, RAM Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C44-25I/PQ
✅ Drop-In✓ In Stock
$9.85 / Unit
View Datasheet →PIC17C44-25E/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C44T-25E/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C44T-25I/PT
✅ Drop-In✓ In Stock
$6.08 / Unit
View Datasheet →PIC17C44-16I/PQ
✅ Drop-In✓ In Stock
$15.5 / Unit
View Datasheet →PIC17C44-25I/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C44T-25I/PQ Maximum Ratings & Electrical Characteristics
| Core | PIC 8-bit RISC |
| Series | PIC 17C |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 16 KB (8K x 16) |
| RAM Size | 454 x 8 bytes |
| Maximum Clock Frequency | 33 MHz |
| Instruction Cycle | 121 ns at 25 MHz |
| MIPS | 8.25 MIPS |
| Operating Voltage (VDD) | 5 V |
| I/O Pins | 33 |
| Instruction Set | 58 single-word instructions |
| Package | 44-MQFP (10x10 mm) |
| Operating Temperature | -40C to +85C (Industrial) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC17C44T-25I/PQ Pin Configuration
| Pin 1 | RA0/INT — PORTA bit 0 / External interrupt |
| Pin 2 | RA1 — PORTA bit 1 |
| Pin 3 | RA2 — PORTA bit 2 |
| Pin 4 | RA3 — PORTA bit 3 |
| Pin 5 | RA4/T0CKI — PORTA bit 4 / Timer 0 clock input |
| Pin 6 | VDD — Positive supply (5V) |
| Pin 7 | OSC1/CLKIN — Crystal/clock input |
| Pin 8 | OSC2/CLKOUT — Crystal/clock output |
| Pin 9 | VSS — Ground |
| 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 | RC4 — PORTC bit 4 |
| Pin 15 | RC5 — PORTC bit 5 |
| Pin 16 | RC6 — PORTC bit 6 |
| Pin 17 | RC7 — PORTC bit 7 |
| Pin 18 | RB0/INT0 — PORTB bit 0 / External interrupt 0 |
| Pin 19 | RB1/INT1 — PORTB bit 1 / External interrupt 1 |
| Pin 20 | RB2/INT2 — PORTB bit 2 / External interrupt 2 |
| Pin 21 | RB3 — PORTB bit 3 |
| Pin 22 | RB4 — PORTB bit 4 |
| Pin 23 | RB5 — PORTB bit 5 |
| Pin 24 | RB6 — PORTB bit 6 |
| Pin 25 | RB7 — PORTB bit 7 |
| Pin 26 | RD0 — PORTD bit 0 |
| Pin 27 | RD1 — PORTD bit 1 |
| Pin 28 | RD2 — PORTD bit 2 |
| Pin 29 | RD3 — PORTD bit 3 |
| Pin 30 | RD4 — PORTD bit 4 |
| Pin 31 | RD5 — PORTD bit 5 |
| Pin 32 | RD6 — PORTD bit 6 |
| Pin 33 | RD7 — PORTD bit 7 |
| Pin 34 | RE0 — PORTE bit 0 |
| Pin 35 | RE1 — PORTE bit 1 |
| Pin 36 | RE2 — PORTE bit 2 |
| Pin 37 | MCLR/VPP — Master clear / programming voltage input |
| Pin 38 | RA5 — PORTA bit 5 |
| Pin 39 | RA6 — PORTA bit 6 |
| Pin 40 | RA7 — PORTA bit 7 |
| Pin 41 | AVSS — Analog ground |
| Pin 42 | AVDD — Analog positive supply (5V) |
| Pin 43 | VSS — Ground |
| Pin 44 | VDD — Positive supply (5V) |
Typical Applications
PIC17C44T-25I/PQ is suitable for 7 applications: Industrial Automation Controllers, Embedded Instrumentation Front-Ends, Motor Control Front-Ends, White Goods Appliance Control, Legacy Control Board Retrofits, Security / Access Control Panels, Point-of-Sale Terminal Embedded Control.
Industrial Automation Controllers
The PIC17C44T-25I/PQ fits industrial automation controllers because of its 25 MHz core (8.25 MIPS), 33 I/O pins, and 454-byte RAM, which together support PID loops, keypad/LED multiplexing, and parallel I/O expansion via shift registers. Industrial-grade screening (-40C to +85C, the 'I' suffix) lets the part operate reliably on the factory floor, and the OTP EPROM keeps firmware locked against field tampering. Placed on a backplane with opto-isolated 24V I/O and a 5V LDO, it typically drives triac/relay outputs while sampling analog sensors through an external ADC. The main trade-off versus a flash-based PIC18F is the OTP memory: firmware changes require a new physical part.
Recommended
Embedded Instrumentation Front-Ends
For embedded instrumentation front-ends, the PIC17C44T-25I/PQ's 8.25 MIPS performance and 33 I/O count let it run character-LCD drivers, scan keypads, and serial-stream data to a host PC over RS-232/TTL UART. The 454 bytes of RAM comfortably buffer one or two display lines plus a packet of measured values. Compared with a PIC16C, the PIC17C44's faster instruction cycle reduces measurement loop latency, improving transient capture in bench-top data loggers. Design tip: budget ~120 bytes for the LCD driver, leaving ~300 bytes for application variables - adequate for typical instrumentation firmware.
Recommended
Motor Control Front-Ends
The PIC17C44T-25I/PQ serves well as a motor control front-end for small DC motors, stepper indexers, and triac-driven AC loads thanks to its 33 I/O pins and 121 ns instruction cycle, which delivers deterministic step rates and zero-crossing detection. Each I/O can sink/source enough current to drive an opto-coupler or low-side MOSFET driver directly, simplifying the BOM. Pairing the MCU with an H-bridge driver such as an external discrete FET half-bridge keeps the firmware responsive while the driver IC handles the high-current switching. The OTP EPROM is a benefit in this application: production firmware never gets accidentally overwritten during motor noise events.
Recommended
White Goods Appliance Control
Appliance controllers in washing machines, dishwashers, and ovens commonly used the PIC17C44T-25I/PQ because its 33 I/O accommodates keypad scanning, 7-segment LED multiplexing, and triac phase-control outputs from a single chip. The industrial temperature rating (-40C to +85C) handles the thermal environment of a closed appliance chassis, and the OTP EPROM locks the firmware against field tampering or accidental erase. Placed on a daughter card with opto-isolated mains interfaces, the PIC17C44 reads sensors (water level, temperature) and drives the user interface while a separate AC zero-cross circuit handles power control. Design consideration: use a single 5V regulator (e.g., MCP1700) and isolate the digital ground from the power stage.
Recommended
Legacy Control Board Retrofits
The PIC17C44T-25I/PQ is widely used in legacy control board retrofits because Microchip's PIC17C family has been in production since the 1990s, and many installed boards carry socketed PIC17C44s that need identical replacements. A drop-in 44-MQFP part with the same 16 KB OTP, 25 MHz clock, and I/O pinout restores functionality without any board redesign. Engineers maintaining industrial equipment, HVAC, and OEM test instruments specify this part specifically for field-service replacements where firmware compatibility is mandatory. Verify the original was the 44-MQFP 'PQ' variant (vs PLCC 'L' or TQFP 'PT') before ordering.
Recommended
Security / Access Control Panels
In security and access control panels, the PIC17C44T-25I/PQ's 33 I/O pins scan keypads, drive piezo buzzers, and multiplex status LEDs while the OTP EPROM keeps the access-control firmware permanent and tamper-resistant. At 8.25 MIPS the device runs debounce, PIN validation, and Wiegand-card-emulation timing comfortably without timing slacks. The industrial temperature grade ensures cold-start reliability in outdoor-mounted panels. Trade-off: for new designs, prefer flash-based PIC18F442 so firmware updates can be applied in the field without swapping the MCU.
Recommended
Point-of-Sale Terminal Embedded Control
PIC17C44T-25I/PQ was adopted in early point-of-sale terminals as a peripheral controller for keypad, magnetic-stripe reader, and printer interfaces. The 33 I/O lines map directly to keypad rows/columns, LCD data bus, and UART peripherals (cash drawer kicker, printer handshake). With 454 bytes of RAM the firmware can buffer a transaction and assemble serial messages for the main processor. A 5V LDO such as MCP1700 provides the supply, and the OTP EPROM protects the firmware IP from extraction. Modern designs should move to PIC18F or dsPIC for USB and cryptography support.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C44T-25I/PQ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C44-25I/PQ | PIC17C44-25E/PQ | PIC17C44T-25E/PQ | PIC17C44T-25I/PT | PIC17C44-16I/PQ | PIC17C44-25I/L |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-MQFP (PQ) 10x10 mm | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same | 44-TQFP (PT) - thinner body, same pin pitch | 44-MQFP (PQ) - same | 44-PLCC (L) - J-lead, requires PLCC socket/footprint |
| Program Memory | 16 KB OTP | 16 KB OTP | 16 KB OTP | 16 KB OTP | 16 KB OTP | 16 KB OTP | 16 KB OTP |
| Maximum Clock | 25 MHz (33 MHz input) | 25 MHz | 25 MHz | 25 MHz | 25 MHz | 16 MHz (slower) | 25 MHz |
| Temperature Grade | Industrial -40C to +85C | Industrial | Extended -40C to +125C | Extended -40C to +125C | Industrial | Industrial | Industrial |
| RAM | 454 bytes | 454 bytes | 454 bytes | 454 bytes | 454 bytes | 454 bytes | 454 bytes |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 | 33 |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | NRND | NRND |
| Price (qty 1, USD) | 13.50 | 13.20 | 14.10 | 14.30 | 13.75 | 12.40 | 13.80 |
Key Differentiators
- Pin-compatible with modern flash-based PIC18F442 (vs PIC18F442)
- Higher throughput than PIC16C at same clock (vs PIC16C series (e.g. PIC16LF877A-I/P))
- Same die across multiple temperature and packaging suffixes (vs PIC17C44-25E/PQ (extended temp))
Design Notes
Estimated: at VDD=5V, I_RUN ~= 30 mA active at 25 MHz (typical, per Microchip datasheet DC characteristics). A 100 mA LDO such as MCP1700-5002E provides ample headroom with adequate bypass capacitance. Place a 10 uF bulk + 100 nF ceramic + 10 nF high-frequency decoupling trio directly at the VDD/AVDD pins to suppress switching noise on the internal clock tree. Run separate analog and digital ground pours tying back to a single point near the MCP1700 to avoid ground-bounce injecting noise into ADC reads (if used).
The 44-MQFP (PQ) package has a typical theta_JA around 45 C/W (estimated; not explicitly published for this package). At I_RUN=30 mA, dissipation is ~150 mW, giving a junction rise of ~7 C above ambient - well inside the -40C to +85C industrial range. For sealed enclosures with no airflow, keep ambient at least 10 C below the maximum to avoid thermal sag. No heatsink required for normal operation; avoid placing the package near hot analog passives.
Estimated: route the 25 MHz crystal traces (OSC1/OSC2) as short, symmetric, ground-shielded traces within 10 mm of the MCU; place load capacitors (typically 22 pF each) on the crystal side, not at the MCU side. Keep the MCLR/VPP line short and add a 10 kohm pull-up to VDD plus a 100 nF to ground for noise immunity; route it away from PWM/relay outputs. Place all decoupling caps within 3 mm of the VDD/VSS pin pairs, with the smaller ceramic closer to the MCU.
Three pitfalls commonly catch new users of the PIC17C44T-25I/PQ: (1) The OTP EPROM is one-time programmable - test firmware extensively on a windowed (JW) sample before committing to OTP parts, since a programming error is permanent. (2) The 'I' vs 'E' temperature suffix matters - using an industrial (-40C to +85C) part in an extended-temperature application will fail at high temperatures. (3) The 44-MQFP (PQ) package is pin-compatible with PIC18F442 - if you migrate designs, verify the VDD/VSS pin positions match because PIC18F family pinouts may differ slightly on the 44-pin TQFP variant.
Compliance Information
RoHS compliance per Microchip product page; AEC-Q100 not applicable for industrial-grade MCU. NRND lifecycle status as of 2026-09-25 per Microchip PIC17C44 product page; PIC18F442 is the recommended successor.
