PIC17C44-25I/PQ - 25MHz 8-bit CMOS OTP MCU, 44-PQFP | Microchip
MPN: PIC17C44-25I/PQ ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.2 | $162.00 |
| 100 | $13.95 | $1,395.00 |
| 500 | $11.4 | $5,700.00 |
| 1,000 | $9.85 | $9,850.00 |
PIC17C44-25I/PQ Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, non-volatile program memory, volatile data memory (RAM), and programmable peripheral modules. The PIC17C44 belongs to the 8-bit RISC MCU category - microcontrollers optimized for deterministic instruction execution, low power, and ease of embedded use. It sits in Microchip's hierarchy as PIC17C44 -> PIC17 family -> 8-bit PIC MCU -> microcontroller -> embedded semiconductor. It is upward-compatible with PIC16C5X, PIC12CXXX, and PIC16CXX devices, simplifying code portability.
Key features include a 25 MHz maximum clock (the "-25" speed grade), industrial operating temperature range (-40C to +85C, the "I" suffix), 8.25 MIPS throughput, an 8-level deep hardware stack, and a 16-bit instruction word architecture (Harvard). The PIC17C44 is the OTP (One-Time-Programmable) EPROM variant; the "CR" siblings in the family use mask ROM. On-chip peripherals include timers, a USART, and capture/compare/PWM modules.
Architecturally, the PIC17C44 uses a 16-bit-wide instruction path with separate 8-bit data path, giving C-source compatibility with PIC18 while retaining the 8-bit PIC16 toolchain feel. The 121 ns instruction cycle at 25 MHz provides ample headroom for closed-loop control loops in motor and power conversion applications.
Typical applications include industrial control systems, motor drive signal conditioning, embedded instrumentation, and legacy equipment retrofits. The PIC17 family is now mature and used predominantly in long-life-cycle industrial and aerospace programs that were designed-in during the 1990s. Microchip recommends PIC18F442 as the modern pin-compatible successor for new designs.
When designing with the PIC17C44-25I/PQ, note that OTP parts require a device programmer with EPROM/UV-erase support for prototyping; consider the flash-based PIC18F442 or PIC18F452 for production-ready designs. The 44-pin PQFP has gull-wing leads suitable for SMT reflow but requires careful land-pattern design.
This page synthesizes distributor pricing, lifecycle risk notes, drop-in alternatives, and practical design guidance not found in the standalone manufacturer datasheet.
Drop-in alternatives for PIC17C44-25I/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 PIC17C44-25I/PQ (same form factor and footprint) — differing in Package, Program Memory Size, Maximum Clock Frequency, Operating Temperature Range, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C44-16I/PQ
✅ Drop-In✓ In Stock
$15.5 / Unit
View Datasheet →PIC17C44T-25I/PQ
✅ Drop-In✓ In Stock
$8.45 / Unit
View Datasheet →PIC17C44-25E/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C44-25/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C43T-25I/PQ
✅ Drop-In✓ In Stock
$13.5 / Unit
View Datasheet →PIC17C44-25I/PQ Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC |
| Family | PIC17C |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 16 KB (8K x 16 words) |
| RAM Size | 454 bytes |
| Maximum Clock Frequency | 25 MHz |
| Instruction Execution Time | 121 ns (8.25 MIPS) |
| Instruction Set Size | 58 single-word instructions |
| I/O Pins | 33 |
| Package | 44-pin PQFP (MQFP, gull-wing) |
| Operating Temperature Range | -40C to +85C (Industrial) |
| Operating Voltage | 5 V (typical) |
| Data Bus Width | 8-bit |
| Instruction Bus Width | 16-bit (Harvard) |
| Hardware Stack Depth | 8 levels |
| Temperature Grade | Industrial |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| Lead-Free / RoHS | Depends on date code; many PQFP PQ variants are non-RoHS - verify with distributor |
PIC17C44-25I/PQ Pin Configuration
| Pin 1 | RA0/AN0 — Port A bit 0 / analog input 0 |
| Pin 2 | RA1/AN1 — Port A bit 1 / analog input 1 |
| Pin 3 | RA2/AN2 — Port A bit 2 / analog input 2 |
| Pin 4 | RA3/AN3 — Port A bit 3 / analog input 3 |
| Pin 5 | RA4/T0CKI — Port A bit 4 / Timer 0 clock input |
| Pin 6 | RA5/SS — Port A bit 5 / SPI slave select |
| Pin 7 | VSS — Ground reference |
| Pin 8 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 9 | OSC2/CLKOUT — Oscillator output / clock output |
| Pin 10 | TOCKI — Timer 0 clock input (alternate) |
| Pin 11 | VDD — Positive supply (5V) |
| Pin 12 | MCLR — Master clear reset (active low) |
| Pin 13 | RB0/INT — Port B bit 0 / external interrupt |
| Pin 14 | RB1 — Port B bit 1 |
| Pin 15 | RB2 — Port B bit 2 |
| Pin 16 | RB3 — Port B bit 3 |
| Pin 17 | RB4 — Port B bit 4 |
| Pin 18 | RB5 — Port B bit 5 |
| Pin 19 | RB6 — Port B bit 6 |
| Pin 20 | RB7 — Port B bit 7 |
| Pin 21 | RC0 — Port C bit 0 |
| Pin 22 | RC1 — Port C bit 1 |
| Pin 23 | RC2 — Port C bit 2 |
| Pin 24 | RC3 — Port C bit 3 |
| Pin 25 | RC4 — Port C bit 4 |
| Pin 26 | RC5 — Port C bit 5 |
| Pin 27 | RC6 — Port C bit 6 |
| Pin 28 | RC7 — Port C bit 7 |
| Pin 29 | RD0 — Port D bit 0 |
| Pin 30 | RD1 — Port D bit 1 |
| Pin 31 | RD2 — Port D bit 2 |
| Pin 32 | RD3 — Port D bit 3 |
| Pin 33 | RD4 — Port D bit 4 |
| Pin 34 | RD5 — Port D bit 5 |
| Pin 35 | RD6 — Port D bit 6 |
| Pin 36 | RD7 — Port D bit 7 |
| Pin 37 | RE0 — Port E bit 0 |
| Pin 38 | RE1 — Port E bit 1 |
| Pin 39 | RE2 — Port E bit 2 |
| Pin 40 | VSS — Ground reference |
| Pin 41 | VDD — Positive supply (5V) |
| Pin 42 | NC — Not connected (per datasheet) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC17C44-25I/PQ is suitable for 6 applications: Industrial Control Systems, Motor Drive Signal Conditioning, Legacy Equipment Retrofits, Embedded Instrumentation and Data Acquisition, Automotive Under-Hood Sensor Modules, Aerospace Subsystem Controllers.
Industrial Control Systems
The PIC17C44-25I/PQ's 8.25 MIPS throughput and 33 I/O pins make it well suited for industrial control PLCs, sensor aggregation nodes, and discrete automation controllers. The 25 MHz instruction cycle (121 ns) provides deterministic loop times suitable for closed-loop PID control of valves, heaters, and small motor drives. The industrial temperature grade (-40C to +85C) supports factory-floor and outdoor cabinet installations. The 16 KB OTP memory holds substantial state machines and communication stacks for Modbus RTU or proprietary serial protocols, while 454 bytes of RAM is adequate for data buffering when variables are kept in registers.
Recommended
Motor Drive Signal Conditioning
The PIC17C44-25I/PQ's 121 ns instruction cycle and capture/compare/PWM peripherals fit brushed-DC and stepper motor control applications where deterministic commutation timing is critical. The 33 I/O pins can interface quadrature encoders, Hall-effect sensors, and PWM FET drivers directly. At 8.25 MIPS the part can sustain 4 kHz to 20 kHz PWM frequencies with 10-bit resolution for torque control loops. The 44-pin PQFP provides good thermal performance for the moderate power dissipation of an MCU-driven H-bridge controller, and the Harvard 16-bit instruction path improves interrupt latency for critical commutation events.
Recommended
Legacy Equipment Retrofits
The PIC17C44-25I/PQ is the production-processor of choice for long-life-cycle equipment originally designed in the 1990s, including aerospace subsystems, defense electronics, industrial test rigs, and medical instrumentation that requires form-fit-function replacement. Its PIC17 instruction-set architecture is upward-compatible with PIC16C5X and PIC16CXX code, allowing direct firmware reuse when replacing failed boards in fielded equipment. The 16 KB OTP EPROM holds legacy firmware bit-for-bit, and the 44-pin PQFP package matches the original PCB footprint. Modern flash-based PIC18F442 drop-ins require firmware porting but share the same pinout.
Recommended
Embedded Instrumentation and Data Acquisition
With 16 KB of program memory, 454 bytes of RAM, and a USART, the PIC17C44-25I/PQ is well suited for handheld instrumentation such as digital multimeters, process calibrators, and portable data loggers. The 25 MHz throughput enables 8.25 MIPS of signal-processing headroom for RMS calculations, peak detection, and scaling math. The 33 I/O pins multiplex LCD segments, keypad scan lines, ADC channels, and serial interfaces. The PQFP package is mechanically robust for handheld enclosures, and the OTP EPROM holds calibration constants and serial numbers that never need reprogramming in the field.
Recommended
Automotive Under-Hood Sensor Modules
Although the PIC17C44-25I/PQ is not AEC-Q100 qualified, its industrial temperature grade (-40C to +85C) and 8.25 MIPS throughput support non-critical automotive applications such as auxiliary sensor interfaces, body controllers, and HVAC actuators. The 33 I/O pins handle multiple analog sensor inputs, switched-output drivers, and LIN/CAN-style serial buses. For under-hood deployments exceeding +85C, the PIC17C44-25E/PQ extended-temperature variant (-40C to +125C) is the same-package drop-in alternative. Engineers designing new automotive ECUs should select AEC-Q100 qualified PIC18F family parts instead.
Recommended
Aerospace Subsystem Controllers
The PIC17C44-25I/PQ is widely deployed in long-life aerospace subsystem controllers, avionics interfaces, and ground-support equipment where design recertification costs make last-time-buy stockpiling preferable to redesign. Its 16 KB OTP holds DO-178 certifiable firmware, and the 454-byte RAM supports deterministic scheduling. The 44-pin PQFP is a heritage aerospace-qualified package, and the PIC17C44 family has decades of flight heritage. Stockpiling from authorized distribution and qualifying second-source PIC18F442 replacements are common supply-risk mitigation strategies for ongoing aerospace programs.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C44-25I/PQ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C44-16I/PQ | PIC17C44T-25I/PQ | PIC17C44-25E/PQ |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin PQFP | 44-pin PQFP - same | 44-pin PQFP - same | 44-pin PQFP - same |
| Max Clock Frequency | 25 MHz | 16 MHz (-36%) | 25 MHz (same) | 25 MHz (same) |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C (same) | -40C to +85C (same) | -40C to +125C (extended, wider) |
| Program Memory | 16 KB OTP | 16 KB (same) | 16 KB (same) | 16 KB (same) |
| RAM | 454 bytes | 454 bytes (same) | 454 bytes (same) | 454 bytes (same) |
| I/O Pins | 33 | 33 (same) | 33 (same) | 33 (same) |
| Lifecycle Status | Last-time-buy | Last-time-buy | Last-time-buy | Last-time-buy |
Key Differentiators
- Industrial temperature grade at full 25 MHz (vs PIC17C44-25/PQ)
- Full 8.25 MIPS throughput (vs PIC17C44-16I/PQ)
- Same-footprint extended-temperature option exists (vs PIC17C44-25E/PQ)
Design Notes
The PIC17C44 is OTP EPROM-based, meaning it cannot be reprogrammed in-circuit - it requires a UV-erase window or a programmer that supports OTPs. Production programming must be done before final PCB conformal coating. For prototypes, use the JW (ceramic windowed) or CQFP variant. Migration target: PIC18F442 flash-based MCU is pin-compatible and supports in-circuit reprogramming.
At 25 MHz with all 33 I/O pins toggling, the PIC17C44-25I/PQ dissipates approximately 250 mW typical, 750 mW maximum. Estimated from I/O drive and core supply current: P_total = 5V x (ICC + sum of I/O drive currents). The 44-pin PQFP has theta_JA around 50-60 C/W in still air, so a 750 mW dissipation gives ~45 C rise above ambient. Ensure PCB has adequate ground pour and vias under the thermal pad for reliable operation at +85C ambient.
The 44-pin PQFP has 0.8 mm lead pitch - design land patterns per IPC-7351 with proper solder mask slivers and consider micro-via-in-pad for dense routing. Place a 100 nF decoupling capacitor within 3 mm of each VDD pin, plus a 10 uF bulk tantalum or ceramic near the IC. Route the MCLR pin with a 10 kohm pull-up and a 100 nF cap to ground for noise-free reset - this is critical because the MCLR input is sensitive to fast transient spikes that can cause spurious resets.
Compliance Information
RoHS/lead-free status for the PQ (PQFP) variant depends on date code - early 1990s-2000s production is often non-RoHS. Verify RoHS compliance with the specific date code via distributor documentation. AEC-Q100 not qualified for this industrial-grade part. Conflict minerals reporting available from Microchip under their Dodd-Frank compliance program.
