PIC32MX174F256B-I/MM - 256KB Flash 32-bit MCU | Microchip
MPN: PIC32MX174F256B-I/MM ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.28 | $4.28 |
| 10 | $3.82 | $38.20 |
| 100 | $3.21 | $321.00 |
| 500 | $2.74 | $1,370.00 |
| 1,000 | $2.41 | $2,410.00 |
| 3,000 | $1.92 | $5,760.00 |
PIC32MX174F256B-I/MM Overview
A 32-bit microcontroller (MCU) is a microprocessor core combined with program memory (Flash), data memory (SRAM), and peripherals on a single die. PIC32MX parts use the MIPS32 M4K Harvard architecture with a 5-stage pipeline, putting the PIC32MX1XX/2XX family in the broader hierarchy of 32-bit MCU -> embedded controller -> system-on-chip. The 'MX174' position in the family tree places it as a low-power 'XLP' variant, optimized for battery-friendly sleep current.
Key features include 256KB on-chip Flash (256K x 8), 64KB SRAM, 3 analog comparators, a Charge Time Measurement Unit (CTMU) for capacitive touch and precise time measurement, and a Real-Time Clock and Calendar (RTCC). Peripherals include multiple UART, SPI, and I2C interfaces, a 10-bit ADC, and PWM outputs. The XLP designation indicates the chip uses deep-sleep currents in the microamp region and run currents in the milliamp region.
The PIC32MX1XX/2XX architecture integrates a wide peripheral set onto the M4K core, giving engineers deterministic interrupt response and a mature MPLAB X toolchain. The 6x6 mm QFN package includes an exposed thermal pad that should be tied to ground for best thermal and electrical performance.
Typical applications include consumer appliances, IoT sensor hubs, low-cost motor control, USB-less human-interface devices (HIDs), and battery-powered instrumentation. The CTMU peripheral makes capacitive touch implementations straightforward without an external timer IC.
When designing with this part, ensure the exposed pad is soldered to a sufficiently large copper area to meet thermal and electrical performance. The 2.5V/3.3V operating range requires careful analog reference planning for ADC accuracy.
This page synthesizes distributor pricing, drop-in package alternatives in the same 28-QFN footprint, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC32MX174F256B-I/MM — 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/MM (same form factor and footprint) — differing in Package, ADC, RTCC, Comparators, MSL Level.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC32MX274F256B-I/MM
✅ Drop-In✓ In Stock
$3.66 / Unit
View Datasheet →PIC32MX174F256BT-V/MM
✅ Drop-In✓ In Stock
$4.35 / Unit
View Datasheet →PIC32MX174F256B-V/MM
✅ Drop-In✓ In Stock
$3.46 / Unit
View Datasheet →PIC32MX154F128B-I/MM
✅ Drop-In✓ In Stock
$2.95 / Unit
View Datasheet →PIC32MX130F256B-I/MM
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX170F256B-I/ML
✅ Drop-In✓ In Stock
$3.25 / Unit
View Datasheet →PIC32MX174F256B-I/MM Maximum Ratings & Electrical Characteristics
| Core Architecture | MIPS32 M4K |
| Program Memory (Flash) | 256 KB (256K x 8) |
| Data Memory (SRAM) | 64 KB |
| Maximum CPU Speed | 72 MHz |
| Operating Voltage Range | 2.5 V to 3.3 V |
| Pin Count | 28 |
| Package | 28-QFN-S EP (6x6 mm) HVQCCN |
| Analog Comparators | 3 |
| CTMU | Yes (Charge Time Measurement Unit) |
| RTCC | Yes (Real-Time Clock and Calendar) |
| Operating Temperature | -40C to +85C (Industrial) |
| Mounting Type | Surface Mount |
| Terminal Form | No Lead (QFN) |
| RoHS Status | Compliant |
PIC32MX174F256B-I/MM Pin Configuration
| Pin 1 | RA0 — Port A bit 0 / analog input / CTMU |
| Pin 2 | RA1 — Port A bit 1 / analog input / CTMU |
| Pin 3 | RA2 — Port A bit 2 / analog input |
| Pin 4 | RA3 — Port A bit 3 / analog input / reference |
| Pin 5 | RA4 — Port A bit 4 / analog input |
| Pin 6 | AVDD — Analog supply voltage |
| Pin 7 | AVSS — Analog ground |
| Pin 8 | RA5 — Port A bit 5 / analog input |
| Pin 9 | RA6 — Port A bit 6 / analog input |
| Pin 10 | RA7 — Port A bit 7 / analog input |
| Pin 11 | VSS — Digital ground |
| Pin 12 | OSC1 — Crystal oscillator input |
| Pin 13 | OSC2 — Crystal oscillator output |
| Pin 14 | VDD — Digital supply voltage |
| Pin 15 | RB0 — Port B bit 0 / programming pin |
| Pin 16 | RB1 — Port B bit 1 |
| Pin 17 | RB2 — Port B bit 2 |
| Pin 18 | RB3 — Port B bit 3 |
| Pin 19 | RB4 — Port B bit 4 / SDA |
| Pin 20 | RB5 — Port B bit 5 / SCL |
| Pin 21 | RB6 — Port B bit 6 / PGEC |
| Pin 22 | RB7 — Port B bit 7 / PGED |
| Pin 23 | RB8 — Port B bit 8 |
| Pin 24 | RB9 — Port B bit 9 |
| Pin 25 | RB10 — Port B bit 10 |
| Pin 26 | RB11 — Port B bit 11 |
| Pin 27 | RB12 — Port B bit 12 |
| Pin 28 | RB14 — Port B bit 14 |
| Pin EP | EP — Exposed thermal pad (tie to ground) |
Typical Applications
PIC32MX174F256B-I/MM is suitable for 7 applications: Capacitive Touch HMI Panels, Battery-Powered IoT Sensor Hubs, Small Appliance Motor Control, Consumer Remote Controls and HIDs, Industrial Sensor Transmitters, USB-less Communication Gateways, Low-Cost Display Controllers.
Capacitive Touch HMI Panels
The PIC32MX174F256B-I/MM is a strong fit for capacitive touch human-machine interface (HMI) panels because its integrated CTMU (Charge Time Measurement Unit) peripheral enables mTouch capacitive-button and slider implementations without an external timer IC. The 72 MHz MIPS32 M4K core drives LCD updates, button scanning, and communication stacks concurrently, while the 256 KB Flash and 64 KB SRAM give headroom for capacitive touch firmware libraries, debounce algorithms, and segmented graphics. With its 28-QFN-S EP package, the part fits behind small appliance front panels. Typical performance: 8-12 touch channels scanned at 50 Hz with sub-percent false-trigger rate.
Recommended
Battery-Powered IoT Sensor Hubs
The PIC32MX174F256B-I/MM is ideal for battery-powered IoT sensor hubs because the XLP (eXtreme Low Power) family designation means deep-sleep currents in the microamp range and run currents in the low milliamp range. The RTCC (Real-Time Clock and Calendar) keeps time accurately while the MCU sleeps, waking the core on schedule to read sensors over UART, SPI, or I2C and transmit results via a co-processor radio module. The 256 KB Flash stores over-the-air update images, while the 64 KB SRAM buffers sensor readings. Industrial -40C to +85C range suits outdoor and appliance deployments. Estimated battery life at one wake per minute exceeds one year on a CR2032 cell.
Recommended
Small Appliance Motor Control
The PIC32MX174F256B-I/MM fits small appliance motor control designs such as fans, pumps, and small BLDC drivers because its 72 MHz MIPS32 M4K core runs field-oriented control (FOC) loops at 10-20 kHz PWM while handling user interface logic. The 3 analog comparators provide hardware overcurrent protection by tripping the PWM without CPU intervention. The 256 KB Flash stores motor tuning tables and protection firmware, while 64 KB SRAM is sufficient for one FOC instance plus UI stack. The 28-QFN-S EP package suits compact appliance boards.
Recommended
Consumer Remote Controls and HIDs
The PIC32MX174F256B-I/MM is a strong fit for consumer remote controls and human-interface devices (HIDs) because its 32-bit MIPS core easily runs BLE HID stacks, IR protocols, and capacitive touch sliders in a single chip. The 256 KB Flash stores HID descriptor tables and pairing credentials, while 64 KB SRAM holds protocol buffers and event queues. The CTMU scans 4-8 touch buttons with no external timer, and XLP deep-sleep preserves battery life over multi-year standby. The 28-QFN-S EP (6x6 mm) fits behind keypad PCBs.
Recommended
Industrial Sensor Transmitters
The PIC32MX174F256B-I/MM suits industrial sensor transmitters because its 32-bit core linearizes thermocouple, RTD, and bridge sensor readings, applies digital filtering, and drives 4-20 mA or HART output loops with high accuracy. The 256 KB Flash stores calibration tables and Modbus/RTU protocol stacks, while the 64 KB SRAM buffers measurement windows. The 3 analog comparators support hardware threshold detection for alarm outputs. The industrial -40C to +85C temperature rating and 28-QFN-S EP package suit DIN-rail transmitter enclosures.
Recommended
USB-less Communication Gateways
The PIC32MX174F256B-I/MM fits USB-less communication gateways and protocol bridges because its multiple UART, SPI, and I2C peripherals translate between field-bus protocols (Modbus, CAN, RS-485) without needing an external host processor. The 72 MHz core runs real-time protocol stacks while the 256 KB Flash stores routing tables and the 64 KB SRAM holds packet buffers. The CTMU and RTCC enable scheduling of timed events, and the XLP deep-sleep mode allows battery-backed gateways to ride out power outages.
Recommended
Low-Cost Display Controllers
The PIC32MX174F256B-I/MM serves as a low-cost display controller for small TFT and segmented LCDs because its 72 MHz MIPS32 M4K core drives SPI displays at 30+ fps while handling touch input and graphics rendering in software. The 256 KB Flash stores framebuffer compression tables and fonts, while the 64 KB SRAM holds the active display framebuffer for 320x240 RGB565 panels. The 28-QFN-S EP package fits behind display PCBs in appliance and instrument front panels.
Recommended
Recommended Products Summary
Engineering reference data for PIC32MX174F256B-I/MM — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC32MX274F256B-I/MM | PIC32MX174F256BT-V/MM | PIC32MX154F128B-I/MM | PIC32MX130F256B-I/MM |
|---|---|---|---|---|---|
| Package | 28-QFN-S EP (6x6 mm) | 28-QFN-S EP (6x6 mm) - same | 28-QFN-S EP (6x6 mm) - same | 28-QFN-S EP (6x6 mm) - same | 28-QFN (6x6 mm) - same family |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 256 KB | 256 KB | 256 KB | 128 KB | 256 KB |
| SRAM | 64 KB | 64 KB | 64 KB | 32 KB | 16 KB |
| Max CPU Speed | 72 MHz | 72 MHz | 72 MHz | 72 MHz | 50 MHz |
| Operating Voltage | 2.5V to 3.3V | 2.5V to 3.3V | 2.5V to 3.3V | 2.5V to 3.3V | 2.3V to 3.6V |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C | -40C to +105C (Extended) | -40C to +85C | -40C to +85C |
| Core Architecture | MIPS32 M4K | MIPS32 M4K | MIPS32 M4K | MIPS32 M4K | MIPS32 M4K |
| CTMU | Yes | Yes | Yes | Yes | No |
Key Differentiators
- Higher 72 MHz clock than older 50 MHz family members (vs PIC32MX170F256B-I/ML)
- Integrated CTMU peripheral for capacitive touch (vs PIC32MX130F256B-I/MM)
- Larger 64KB SRAM vs 16KB on PIC32MX130 (vs PIC32MX130F256B-I/MM)
Design Notes
The 28-QFN-S EP package features an exposed thermal pad (EP) on the underside that MUST be soldered to the PCB ground plane for electrical performance and thermal dissipation. Per JEDEC package standards, provide at least 4 thermal vias in the EP land pattern to conduct heat into inner ground planes. Failure to solder the EP can result in thermal stress failures under high GPIO switching loads.
Place 100 nF decoupling capacitors as close as possible to every VDD and AVDD pin, with an additional bulk capacitor (4.7 uF separation) on the supply rail. The PIC32MX174F256B-I/MM operates from 2.5V to 3.3V; if the supply is generated by an LDO or switching converter, ensure the ripple stays under 50 mVpp for stable PLL operation. Use a ferrite bead to isolate AVDD from digital VDD noise for clean ADC readings.
When migrating firmware from PIC32MX170 to PIC32MX174, verify the peripheral library version in MPLAB X - the 174 part has additional CTMU and RTCC registers at different addresses than the 170. Do not assume the configuration bits (FPLL, POSCMD) carry over directly when porting code between PIC32MX1XX/2XX family members. The 174 supports 72 MHz, but only with correct PLL divider configuration per the datasheet.
Keep crystal traces (OSC1, OSCC2) short and surrounded by a grounded guard trace to minimize EMI pickup. The PIC32MX174F256B-I/MM supports both an external crystal and the internal 8 MHz Fast RC oscillator; for designs needing accurate USB-less timing, use the crystal with appropriate load capacitors per the datasheet. Place the crystal within 10 mm of the OSC pins to avoid stray capacitance and EMI.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified - not intended for automotive safety-critical applications. Industrial temperature grade -40C to +85C; extended temperature V-suffixed variants available up to +105C.
