PIC32MX174F256D-I/PT - 72MHz 32-bit MCU, 256KB Flash, USB | Microchip
MPN: PIC32MX174F256D-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.86 | $5.86 |
| 10 | $5.32 | $53.20 |
| 100 | $4.45 | $445.00 |
| 500 | $3.78 | $1,890.00 |
| 1,000 | $3.21 | $3,210.00 |
PIC32MX174F256D-I/PT Overview
A 32-bit MCU (microcontroller unit) is a single-chip processor integrating CPU core, program memory, data memory, and peripherals. The PIC32MX174 family specifically extends the PIC32 portfolio into XLP territory, achieving lower run, sleep, and deep-sleep currents while pushing 28- and 44-pin device performance up to 72 MHz. The PIC32MX174F256D sits at the top of the PIC32MX1XX/2XX XLP family in Flash density, sitting between the PIC32MX154 (128 KB) and PIC32MX274/5XX/6XX/7XX tiers, while sharing the same peripheral set and pinout as PIC32MX150/170/174/230/250/270 devices in the same package.
Key features include 256 KB single-cycle Flash, 64 KB SRAM, 72 MHz core, full-speed USB 2.0 with on-chip transceiver, 3 analog comparators, CTMU for touch and time-of-flight measurement, RTCC with calendar mode, 5 16-bit timers (Timer1-Timer5), 5 IC/OC/PWM channels, 2 SPI, 2 I2C, and 2 UART modules. The CTMU provides highly accurate time measurement for capacitive touch sensing, while the RTCC keeps accurate wall-clock time in deep-sleep modes consuming only microamps.
The architecture uses a Harvard-style MIPS32 M4K core with 5-stage pipeline, single-cycle Flash access, hardware multiply/divide, and prefetch cache. The 256 KB Flash is organized as 256K x 8 bits and supports 10,000 minimum erase/write cycles per block; the 64 KB SRAM provides 256K x 8 bits of working memory. The integrated USB 2.0 Full-Speed controller eliminates the need for an external PHY, reducing BOM cost for USB device applications such as HID peripherals, CDC virtual COM ports, and USB audio.
Typical applications include USB peripherals (HID, CDC, audio), capacitive touch interfaces using CTMU, low-power IoT sensor nodes with RTCC wake, consumer electronics requiring USB connectivity, industrial control with RTCC timestamping, and battery-powered embedded devices. The XLP deep-sleep currents in the microamp range make it especially attractive for battery or energy-harvesting designs.
When designing with this part, select the appropriate oscillator mode (8 MHz FRC default with PLL for 72 MHz), place the USB DP/DM traces as a 90-ohm differential pair per USB 2.0 specification, and reserve adequate decoupling (0.1uF + 1uF) within 5 mm of each VDD pin. Firmware should also clear the JTAGEN bit in CFGCON if JTAG is unused, freeing PA0/PA1 as standard I/O.
This page synthesizes distributor pricing, drop-in alternatives within the same TQFP-44 footprint, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC32MX174F256D-I/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 PIC32MX174F256D-I/PT (same form factor and footprint) — differing in Package, ADC, Operating Temperature, USB, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC32MX170F256D-I/PT
✅ Drop-In✓ In Stock
$3.55 / Unit
View Datasheet →PIC32MX230F256D-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX270F256D-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX154F128D-I/PT
✅ Drop-In✓ In Stock
$4.65 / Unit
View Datasheet →PIC32MX274F256D-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX150F256D-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX174F256D-I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | MIPS32 M4K (32-bit RISC) |
| Maximum CPU Frequency | 72 MHz |
| Program Memory (Flash) | 256 KB (256K x 8) |
| Data Memory (SRAM) | 64 KB |
| Operating Voltage Range | 2.5 V to 3.6 V (3.3 V typical) |
| I/O Pins | 34 (on 44-pin TQFP) |
| Package | 44-pin TQFP (PT), 10x10 mm |
| USB Controller | USB 2.0 Full-Speed device/host/OTG with on-chip PHY |
| Analog Comparators | 3 |
| CTMU Modules | 1 (Charge Time Measurement Unit) |
| RTCC | Yes (Real-Time Clock/Calendar) |
| Timers | 5 x 16-bit |
| IC/OC/PWM Channels | 5 |
| UART Modules | 2 |
| SPI Modules | 2 |
| I2C Modules | 2 |
| Operating Temperature Range | -40 C to +85 C (industrial) |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| RoHS Status | Compliant |
PIC32MX174F256D-I/PT Pin Configuration
| Pin 1 | RPB15/AN15/PMA0/RG15 — General I/O, analog input, parallel master address |
| Pin 2 | VSS — Ground |
| Pin 3 | VDD — Positive supply voltage (2.5V to 3.6V) |
| Pin 4 | RPB5/USBID/RB5 — General I/O / USB ID pin |
| Pin 5 | RPB6/RB6 — General I/O |
| Pin 6 | RPB7/RB7 — General I/O |
| Pin 7 | RPC0/RC0 — General I/O |
| Pin 8 | RPC1/RC1 — General I/O |
| Pin 9 | RPC2/RC2 — General I/O |
| Pin 10 | RPC3/RC3 — General I/O |
| Pin 11 | VSS — Ground |
| Pin 12 | VDD — Positive supply voltage |
| Pin 13 | PGEC1/AN8/RPB8/RB8 — In-circuit debugger clock / general I/O |
| Pin 14 | PGED1/AN9/RPB9/RB9 — In-circuit debugger data / general I/O |
| Pin 15 | VDD — Positive supply voltage |
| Pin 16 | AVDD — Analog positive supply |
| Pin 17 | AVSS — Analog ground |
| Pin 18 | AN11/RPB11/RB11 — Analog input / general I/O |
| Pin 19 | AN10/RPB10/RB10 — Analog input / general I/O |
| Pin 20 | AN12/RPB12/RB12 — Analog input / general I/O |
| Pin 21 | AN13/RPB13/RB13 — Analog input / general I/O |
| Pin 22 | CVREF-/AN14/RPB14/RB14 — Comparator reference / analog input / general I/O |
| Pin 23 | SOSCI/RPC4/RC4 — Secondary oscillator input / general I/O |
| Pin 24 | SOSCO/RPA4/T1CK/RA4 — Secondary oscillator output / general I/O |
| Pin 25 | D-/RG2 — USB Full-Speed D- data line |
| Pin 26 | D+/RG3 — USB Full-Speed D+ data line |
| Pin 27 | VUSB — USB internal transceiver supply |
| Pin 28 | VSS — Ground |
| Pin 29 | VDD — Positive supply voltage |
| Pin 30 | OC1/RPA0/RA0 — Output compare / general I/O |
| Pin 31 | OC2/RPA1/RA1 — Output compare / general I/O |
| Pin 32 | OSC1/CLKI/RC12 — Primary oscillator input / clock input |
| Pin 33 | OSC2/CLKO/RC15 — Primary oscillator output / clock output |
| Pin 34 | TDO/AN4/RPA8/PMA8/RA8 — JTAG TDO / analog input / general I/O |
| Pin 35 | TCK/AN3/RPA9/PMA9/RA9 — JTAG TCK / analog input / general I/O |
| Pin 36 | TDI/AN2/RPA10/PMA10/RA10 — JTAG TDI / analog input / general I/O |
| Pin 37 | TMS/AN1/RPA11/PMA11/RA11 — JTAG TMS / analog input / general I/O |
| Pin 38 | RTCC/AN0/RPA12/PMA12/RA12 — Real-Time Clock Calendar / analog input / general I/O |
| Pin 39 | CVREF+/AN5/RPA13/PMA13/RA13 — Comparator reference+ / analog input / general I/O |
| Pin 40 | CVREFOUT/RPA14/PMA14/RA14 — Comparator reference output / general I/O |
| Pin 41 | RPA15/PMA15/RA15 — General I/O |
| Pin 42 | VSS — Ground |
| Pin 43 | VDD — Positive supply voltage |
| Pin 44 | RPB0/AN6/RB0 — General I/O / analog input |
Typical Applications
PIC32MX174F256D-I/PT is suitable for 6 applications: USB HID Peripheral (Keyboard/Mouse/Gamepad), Capacitive Touch Sensing with CTMU, USB CDC Virtual COM Port Bridge, Battery-Powered IoT Sensor Node with RTCC Wake, Industrial Real-Time Clock with Timestamping, Consumer Audio Interface (USB Audio Class).
USB HID Peripheral (Keyboard/Mouse/Gamepad)
The PIC32MX174F256D-I/PT is well matched to USB Human Interface Device peripherals thanks to its on-chip USB 2.0 Full-Speed controller and integrated PHY. Operating at 72 MHz, the MIPS32 M4K core can scan a matrix keyboard, drive a HID report at 1000 Hz polling, and handle LED/animation routines without dropping frames. With 256 KB Flash, full HID descriptors and HID-to-serial translation tables fit comfortably. The on-chip pull-ups on the DP line are software-controlled, eliminating an external resistor on the USB connector. Compared to PIC32MX150, the PIC32MX174's XLP deep-sleep keeps idle current in the microamp range, extending battery life on wireless HID dongles. The device enumerates as standard HID class with no custom drivers on Windows, macOS, and Linux hosts.
Recommended
Capacitive Touch Sensing with CTMU
The PIC32MX174F256D-I/PT integrates a Charge Time Measurement Unit (CTMU) which charges a touch sensor capacitance with a known current and measures the resulting voltage ramp time, giving sub-percent resolution on capacitive change. Combined with the 72 MHz MIPS32 M4K core, it can drive 20-50 touch buttons or a 4x4 capacitive matrix while running a debouncing and gesture-detection algorithm. The 256 KB Flash stores full Microchip mTouch firmware libraries, and 64 KB SRAM holds scan history. XLP deep-sleep keeps idle current low between touches, so battery-powered products like remote controls or white-goods keypads can last years on a coin cell. The CTMU also supports water-guard and proximity-sensing firmware for automotive interior switches.
Recommended
USB CDC Virtual COM Port Bridge
For bridging UART peripherals to a USB host, the PIC32MX174F256D-I/PT implements USB CDC class natively using the Microchip MLA CDC Basic library, creating a virtual COM port that operates at up to 1 Mbaud without custom drivers. The two on-chip UART modules can drive RS-232 or RS-485 transceivers at 115.2 kbaud or higher, while the 256 KB Flash accommodates CDC descriptor tables plus the application protocol. At 72 MHz, the M4K core has enough headroom to run Modbus RTU parsing, DMX-512, or NMEA-0183 streams without missing inter-character timing. The USB DP/DM 90-ohm differential pair must be routed per USB 2.0 spec for full-speed signaling, but the integrated PHY removes the need for an external transceiver chip.
Recommended
Battery-Powered IoT Sensor Node with RTCC Wake
The XLP feature on the PIC32MX174F256D-I/PT brings deep-sleep currents into the microamp range while the on-board RTCC keeps accurate wall-clock time, enabling multi-year battery life on periodic wake sensors. Typical sensor node firmware wakes the MCU on RTCC alarm, samples an external I2C sensor or SPI ADC, transmits via UART or another radio, and returns to deep-sleep. The 64 KB SRAM buffers the day's measurement results; the 256 KB Flash stores the RTCC alarm scheduler and radio control protocol. At 72 MHz the measurement+transmit cycle completes in milliseconds, so average draw is dominated by deep-sleep current. For solar or energy-harvesting designs, the PIC32MX274 with even better XLP and 96 KB SRAM is a direct upgrade.
Recommended
Industrial Real-Time Clock with Timestamping
Industrial data loggers benefit from the PIC32MX174F256D-I/PT's hardware RTCC with calendar mode, which keeps accurate timestamp in deep-sleep and can timestamp external events with sub-millisecond resolution. The RTCC alarm can interrupt the core on scheduled wake, while the 3 analog comparators detect external threshold crossings without core intervention. The 256 KB Flash stores event buffers, and the 2 UART modules drive RS-485 transceivers for Modbus RTU networks. Industrial temperature range of -40 C to +85 C, RoHS-compliant TQFP-44 package, and Microchip's 15+ year longevity program make this part suitable for factory-floor PLCs, building automation controllers, and sub-station data concentrators.
Recommended
Consumer Audio Interface (USB Audio Class)
The PIC32MX174F256D-I/PT can implement a USB Audio Class 1.0 device, presenting itself to the host as a USB speaker or microphone and streaming 16-bit 48 kHz stereo PCM with negligible CPU load. The on-chip Full-Speed USB and integrated PHY handle the streaming endpoint, while the two I2S peripherals (multiplexed on the SPI pins) drive an external DAC or receive an external ADC. The 72 MHz M4K core has spare cycles for DSP-style sample rate conversion or headphone volume control. At 64 KB SRAM, double-buffered audio frames plus control state all fit comfortably. Compared to PIC32MX130, the PIC32MX174's XLP deep-sleep is useful for portable audio products that sleep when the headphone jack is unplugged.
Recommended
Recommended Products Summary
Engineering reference data for PIC32MX174F256D-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC32MX170F256D-I/PT | PIC32MX230F256D-I/PT | PIC32MX270F256D-I/PT | PIC32MX274F256D-I/PT | PIC32MX154F128D-I/PT | PIC32MX150F256D-I/PT |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | 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 | TQFP-44 (PT) - same | TQFP-44 (PT) - same |
| Core Frequency | 72 MHz | 72 MHz | 50 MHz | 72 MHz | 72 MHz | 72 MHz | 40 MHz |
| Flash Memory | 256 KB | 256 KB | 256 KB | 256 KB | 256 KB | 128 KB | 256 KB |
| SRAM | 64 KB | 64 KB | 128 KB | 64 KB | 96 KB | 32 KB | 64 KB |
| USB Controller | FS USB 2.0 with on-chip PHY | FS USB 2.0 with on-chip PHY | FS USB 2.0 with on-chip PHY | FS USB 2.0 with on-chip PHY | FS USB 2.0 with on-chip PHY | FS USB 2.0 with on-chip PHY | FS USB 2.0 with on-chip PHY |
| CTMU Module | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| XLP Deep-Sleep | Yes (XLP family) | Yes | No (lower-tier XLP) | Yes | Yes (enhanced) | Yes | No |
| Operating Voltage | 2.5 V to 3.6 V | 2.5 V to 3.6 V | 2.3 V to 3.6 V | 2.5 V to 3.6 V | 2.5 V to 3.6 V | 2.5 V to 3.6 V | 2.3 V to 3.6 V |
Key Differentiators
- Highest memory density in the PIC32MX1XX/2XX XLP 44-pin family (vs PIC32MX154F128D-I/PT)
- Enhanced XLP deep-sleep current optimization (vs PIC32MX150F256D-I/PT)
- Direct upgrade path to PIC32MX274 with more SRAM (vs PIC32MX274F256D-I/PT)
- Fastest core speed in this package tier (vs PIC32MX230F256D-I/PT)
Design Notes
Place one 0.1 uF ceramic decoupling capacitor as close as possible to each VDD pin (3 of them: pins 3, 12, 15/29/43) and to AVSS/AVDD (pins 16, 17). Use a bulk 4.7-10 uF tantalum or ceramic on the main 3.3V rail. USB VUSB pin (pin 27) requires a 0.01 uF decoupling capacitor per the Microchip datasheet to stabilize the internal USB regulator. The XLP deep-sleep current is in the microamp range, so power-rail leakage from the decoupling caps can dominate idle current; choose X7R ceramics with low DC bias drift.
Route the USB DP (pin 26) and DM (pin 25) traces as a 90-ohm differential pair with continuous reference ground plane, maximum trace length of 50 mm, and no stubs - per USB 2.0 Full-Speed specification. Keep the 12 MHz primary oscillator (pins 32/33) traces short and surrounded by ground. The SOSC pins (23/24) for the 32.768 kHz crystal must be routed away from switching signals to prevent coupling into the RTCC timebase. The ICSP/debug pins (PGEC1/PGED1, pins 13/14) need 4.7k pull-up resistors if the debugger cable is long.
Two common pitfalls: (1) Failing to clear the JTAGEN bit in CFGCON before locking the configuration - if JTAG is enabled, RA0/RA1 lose their I/O function and you cannot use the analog comparators or other peripherals on those pins. (2) Forgetting to set the FSOSCEN bit to enable the secondary oscillator (SOSC) for RTCC; without it, the RTCC will not advance. Also: when migrating firmware from PIC32MX170 to PIC32MX174, review the new XLP-specific deep-sleep registers in the device header - the wake-up source configuration differs slightly.
At 72 MHz with all peripherals active and USB running, the PIC32MX174F256D-I/PT typically draws 30-40 mA from 3.3V (~100-130 mW). The TQFP-44 (PT) package thermal resistance is approximately 50 C/W on a 4-layer JEDEC test board, giving a junction-to-ambient rise of 5-7 C above ambient at full load. In a battery-powered product where the device spends most of its time in deep-sleep, self-heating is negligible. No external heatsink is needed.
Compliance Information
RoHS and REACH compliant per Microchip product page. The industrial -40 C to +85 C temperature grade qualifies this part for general embedded use but not AEC-Q100 automotive; use the PIC32MX174F256D-I/PT only in non-automotive applications or in automotive where AEC-Q100 is not required.