PIC32MX174F256B-I/SO - 72MHz 32-bit XLP MCU, 256KB Flash, 28-SOIC | Microchip
MPN: PIC32MX174F256B-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.94 | $6.94 |
| 10 | $6.05 | $60.50 |
| 100 | $4.92 | $492.00 |
| 500 | $4.18 | $2,090.00 |
| 1,000 | $3.75 | $3,750.00 |
PIC32MX174F256B-I/SO Overview
A 32-bit microcontroller (MCU) is an integrated processor that combines a CPU core, program memory (Flash), working memory (SRAM), and a rich set of peripherals on a single die. Within Microchip's taxonomy, PIC32MX174F256B sits under PIC32MX -> 32-bit PIC MCUs -> MIPS-based MCUs -> Microcontrollers -> Integrated Circuits. Compared to 8/16-bit legacy PIC MCUs, the PIC32MX family executes instructions via the MIPS32 M4K core with 5-stage pipeline, single-cycle hardware multiply, and a 32-bit path for higher data throughput.
Key features include 256 KB single-cycle Flash with Flash prefetch, 64 KB SRAM, hardware multiply/divide, DMA controller, 10-bit 1 Msps ADC, analog comparators, RTCC, I2S/SPI/I2C/UART peripherals, CTMU, PMP, and dedicated USB 2.0 full-speed device/host/OTG controller. Sleep current is rated in the low microamp range, with deep-sleep down to nanoamp levels thanks to the XLP design philosophy, while operating voltage spans 2.3 V to 3.6 V.
The PIC32MX174F256B uses a Harvard architecture with separate Flash and SRAM buses, accelerating simultaneous instruction and data fetches. Dedicated peripheral pin-select (PPS) registers allow flexible remapping of digital peripherals, simplifying PCB layout. The 28-SOIC package delivers 21 usable I/O plus USB D+/D-, oscillator, and JTAG programming pins, while the embedded 8 MHz FRC with PLL scales to 72 MHz CPU clock with USB 48 MHz reference.
Typical applications include consumer USB peripherals (HID, CDC, audio), low-power IoT sensor nodes with USB battery charging, graphic display controllers using PMP, industrial control with CAN bridging via SPI, low-cost audio interfaces leveraging I2S, and ultra-low-power battery-powered instrumentation. The combination of USB, CTMU touch sensing, and XLP currents makes it suited to wearable, BLE-mouse, and remote-control designs.
When designing, note that the I/SO industrial temperature grade is -40C to +85C. A decoupling network of 0.1uF and 10uF should sit within 5 mm of VDD/VSS pairs, and the USB 48 MHz clock must use the dedicated PLL configuration to meet USB full-speed timing. Programming is supported by MPLAB X IDE with MPLAB Harmony v3 framework.
This page synthesizes distributor pricing, 28-SOIC drop-in alternatives within the PIC32MX1XX/2XX family, and practical design notes that go beyond what the manufacturer datasheet alone provides.
Drop-in alternatives for PIC32MX174F256B-I/SO — 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 PIC32MX174F256B-I/SO (same form factor and footprint) — differing in Package, MSL Level, Operating Temperature, Program Memory (Flash), ADC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC32MX174F256BT-I/SO
✅ Drop-In✓ In Stock
$2.74 / Unit
View Datasheet →PIC32MX170F256B-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX170F256BT-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.95 / Unit
View Datasheet →PIC32MX154F128B-I/SO
✅ Drop-In✓ In Stock
$1.69 / Unit
View Datasheet →PIC32MX120F032B-I/SO
✅ Drop-In✓ In Stock
$1.71 / Unit
View Datasheet →PIC32MX174F256B-I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | MIPS32 M4K, 32-bit RISC |
| Maximum CPU Clock | 72 MHz |
| Program Memory (Flash) | 256 KB (256K x 8) |
| Data Memory (SRAM) | 64 KB |
| Operating Voltage Range | 2.3 V to 3.6 V |
| I/O Pins | 21 |
| Package | 28-SOIC (7.50 mm body width) |
| Mounting Type | Surface Mount |
| USB | USB 2.0 Full-Speed Device/Host/OTG |
| Communication Peripherals | I2C, SPI, UART, I2S, PMP |
| Operating Temperature | -40C to +85C (Industrial) |
| Temperature Grade | I (Industrial) |
| MSL Level | 1 |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC32MX174F256B-I/SO Pin Configuration
| Pin 1 | RA3 — General purpose I/O / analog input |
| Pin 2 | RA4 — General purpose I/O |
| Pin 3 | RA5 — General purpose I/O |
| Pin 4 | TMS/RA0 — JTAG TMS / GPIO |
| Pin 5 | TCK/RA1 — JTAG TCK / GPIO |
| Pin 6 | TDO/RA2 — JTAG TDO / GPIO |
| Pin 7 | OSC1/RC12 — Crystal oscillator input |
| Pin 8 | VDD — Supply voltage 2.3 V to 3.6 V |
| Pin 9 | OSC2/RC13 — Crystal oscillator output |
| Pin 10 | RB0 — GPIO / programming PGED1 |
| Pin 11 | RB1 — GPIO / programming PGEC1 |
| Pin 12 | RB2 — GPIO |
| Pin 13 | TDI/RB3 — JTAG TDI / GPIO |
| Pin 14 | RB4 — GPIO |
| Pin 15 | RB5 — GPIO |
| Pin 16 | RB6 — GPIO |
| Pin 17 | RB7 — GPIO |
| Pin 18 | RB8 — GPIO |
| Pin 19 | VSS — Ground |
| Pin 20 | RB9 — GPIO |
| Pin 21 | RB10 — GPIO |
| Pin 22 | RB11 — GPIO |
| Pin 23 | D+ — USB data plus |
| Pin 24 | D- — USB data minus |
| Pin 25 | RC0 — GPIO |
| Pin 26 | RC1 — GPIO |
| Pin 27 | VDD — Supply voltage 2.3 V to 3.6 V |
| Pin 28 | VSS — Ground |
Typical Applications
PIC32MX174F256B-I/SO is suitable for 7 applications: USB HID Consumer Peripheral, Low-Power IoT Sensor Node with USB, Audio Interface with I2S, Industrial Control / CAN Bridge, Touch-Sensing Control Panel, Battery-Charging Power Bank, Graphic Display Controller via PMP.
USB HID Consumer Peripheral
The PIC32MX174F256B-I/SO's integrated USB 2.0 full-speed OTG controller plus 256 KB Flash make it a turnkey solution for HID-class peripherals such as keyboards, mice, and game controllers. The 72 MHz MIPS core executes the USB stack and HID report generator with cycles to spare for capacitive or mechanical scanning. The XLP deep-sleep current keeps battery life of wireless HID mice above 12 months on a single AA cell.
Recommended
Low-Power IoT Sensor Node with USB
XLP run/sleep/deep-sleep currents and USB-OTG allow a single MCU to handle both battery operation and tethered firmware updates. The PIC32MX174F256B-I/SO wakes from deep-sleep on a CTMU comparator or RTCC alarm, samples a sensor over I2C or SPI, and returns to sleep within microseconds. USB 2.0 full-speed provides a built-in bootloader path with no external bridge, reducing BOM and PCB area.
Recommended
Audio Interface with I2S
The I2S peripheral and 64 KB SRAM enable a 16-bit 48 kHz audio playback or capture path on the PIC32MX174F256B-I/SO. DMA offloads sample movement between I2S and SRAM, leaving the MIPS core free for codec control and USB streaming. The 28-SOIC footprint exposes all required I2S signals plus USB for simultaneous charge and audio.
Recommended
Industrial Control / CAN Bridge
PMP, DMA, and 21 I/O at -40C to +85C industrial grade suit the PIC32MX174F256B-I/SO for industrial control panels where it can drive a graphics LCD via PMP while bridging sensor data over SPI to an external CAN controller. The 256 KB Flash supports both USB diagnostics and CANopen or J1939 stacks without external memory.
Recommended
Touch-Sensing Control Panel
The CTMU peripheral and 10-bit ADC on the PIC32MX174F256B-I/SO implement capacitive touch sensing for control panels and appliances. Up to 16 channels can be scanned via DMA, and the XLP currents allow a coin-cell powered remote. USB enables firmware updates in the field, removing the need for ICSP headers on the PCB.
Recommended
Battery-Charging Power Bank
USB-OTG plus I2C battery monitoring allows the PIC32MX174F256B-I/SO to act as the controller in a USB power bank. It negotiates USB current modes, manages charge/discharge FETs, and reports state via LEDs or an OLED. Deep-sleep currents in the nanoamp range extend shelf life when no device is attached.
Recommended
Graphic Display Controller via PMP
The Parallel Master Port (PMP) on the PIC32MX174F256B-I/SO drives small color TFT or OLED panels without an external controller, with 8-bit data and up to 16 control lines. The 72 MHz core handles bitmap blits from Flash to the panel, and USB provides content updates or touch feedback for interactive kiosks.
Recommended
Recommended Products Summary
Engineering reference data for PIC32MX174F256B-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC32MX174F256BT-I/SO | PIC32MX170F256B-I/SO | PIC32MX170F256BT-I/SO | PIC32MX154F128B-I/SO | PIC32MX120F032B-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC | 28-SOIC | 28-SOIC | 28-SOIC | 28-SOIC | 28-SOIC |
| Maximum CPU Clock | 72 MHz | 72 MHz | 72 MHz | 72 MHz | 72 MHz | 40 MHz |
| Flash Memory | 256 KB | 256 KB | 256 KB | 256 KB | 128 KB | 32 KB |
| SRAM | 64 KB | 64 KB | 64 KB | 64 KB | 32 KB | 8 KB |
| USB Peripheral | USB 2.0 FS OTG | USB 2.0 FS OTG | None | None | None | None |
| Operating Voltage | 2.3 V to 3.6 V | 2.3 V to 3.6 V | 2.3 V to 3.6 V | 2.3 V to 3.6 V | 2.3 V to 3.6 V | 2.3 V to 3.6 V |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| I/O Pins | 21 | 21 | 21 | 21 | 21 | 21 |
Key Differentiators
- Integrated USB 2.0 full-speed OTG (vs PIC32MX170F256B-I/SO)
- 256 KB Flash with 64 KB SRAM (vs PIC32MX154F128B-I/SO)
- 72 MHz core vs 40 MHz on legacy parts (vs PIC32MX120F032B-I/SO)
Design Notes
Place a 0.1 uF ceramic decoupling capacitor within 5 mm of every VDD/VSS pin pair on PIC32MX174F256B-I/SO, plus a single 10 uF bulk capacitor near the package. The XLP currents mean that a missing decoupling cap can show up as increased deep-sleep current or unstable USB enumeration at high ambient temperatures.
Ensure the USB 48 MHz clock is sourced from the primary oscillator or 8 MHz FRC with USB PLL configuration as specified in section 30 of the family datasheet. Operating USB at the wrong PLL ratio or without correct board configuration causes USB enumeration failures, not recoverable by the application.
Route the D+ and D+ USB traces as a 90-ohm differential pair on the top layer with a continuous ground reference plane below. Keep the pair length-matched within 150 mil. Adding a 50 mil guard trace tied to ground reduces radiated emissions on industrial designs.
Use Peripheral Pin Select (PPS) to remap UART, SPI, I2C, and I/O functions on PIC32MX174F256B-I/SO. This simplifies PCB layout by letting you keep peripherals on convenient pins. Note that PPS registers must be unlocked and remapped after each POR event; do not skip the unlock sequence.
Compliance Information
RoHS and lead-free compliant per Microchip product page; conflict-minerals declaration on file. Industrial -40C to +85C temperature grade, not AEC-Q100 qualified.
