PIC32MX274F256D-I/ML - 32-bit MCU 256KB Flash 72MHz USB | Microchip
MPN: PIC32MX274F256D-I/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.2 | $4.20 |
| 10 | $3.78 | $37.80 |
| 100 | $3.36 | $336.00 |
| 500 | $2.94 | $1,470.00 |
| 1,000 | $2.52 | $2,520.00 |
PIC32MX274F256D-I/ML Overview
This device belongs to the PIC32MX1XX/2XX 28/44-pin XLP family of ultra-low-power 32-bit microcontrollers. XLP (eXtreme Low Power) technology reduces run, sleep, and deep-sleep currents versus earlier PIC32 generations, while the 72 MHz core on the 28/44-pin variants delivers higher computational throughput than older 50 MHz PIC32MX parts. Within the broader taxonomy, the PIC32MX274F256D sits at microcontroller -> 32-bit MCU -> MIPS M4K core -> Microchip PIC32 family -> PIC32MX2xx sub-family -> PIC32MX27x XLP line.
Key features include 256KB Flash program memory, 64KB SRAM, hardware Full-Speed USB 2.0 device/host/OTG, up to 5 dedicated 16-bit timers, three analog comparators, a Real-Time Clock Calendar (RTCC), and a Charge Time Measurement Unit (CTMU) for capacitive touch and accurate timing. Integrated peripherals cover I2C, SPI, UART, PMP for graphics, and a 10-bit ADC with up to 1 Msps sampling, enabling mixed-signal embedded designs.
The 44-pin QFN package exposes up to 35 usable I/O pins, five 16-bit timers, and multiple PGECx/PGEDx programming pairs for flexible ICSP layout. The CTMU and RTCC make it well-suited to Human Interface Devices (HID), capacitive touch keys, segment LCD control via peripheral mapping, and audio sample-rate timing. Hardware USB eliminates the need for an external transceiver and is a key reason this part is widely used in HID peripherals, audio class USB devices, and embedded host stacks.
Typical applications include USB HID peripherals (keyboards, mice, game controllers), capacitive touch user interfaces, audio playback and USB audio class devices, low-power sensor hubs, industrial control front-ends, and graphics-based segment displays. The combination of low-power XLP modes and 72 MHz performance suits both battery-powered and line-powered products.
Design with this part: place a 10 uF plus 0.1 uF bulk-decoupling network on VDD/VSS, use the exposed thermal pad (EP) to ground for mechanical and thermal performance, and follow Microchip's PIC32 USB hardware checklist for the 90-ohm differential D+/D- impedance.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC32MX274F256D-I/ML — 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 PIC32MX274F256D-I/ML (same form factor and footprint) — differing in ADC, Package, Operating Temperature, RTCC, SRAM.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC32MX270F256D-I/ML
✅ Drop-In✓ In Stock
$4.18 / Unit
View Datasheet →PIC32MX250F256D-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX230F256D-I/ML
✅ Drop-In✓ In Stock
$3.05 / Unit
View Datasheet →PIC32MX170F256D-I/ML
✅ Drop-In✓ In Stock
$3.45 / Unit
View Datasheet →PIC32MX174F256DT-I/ML
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →PIC32MX154F128DT-I/ML
✅ Drop-In✓ In Stock
$1.4 / Unit
View Datasheet →PIC32MX274F256D-I/ML Maximum Ratings & Electrical Characteristics
| Core | MIPS32 M4K 32-bit |
| Family | PIC32MX27x (XLP) |
| Maximum CPU Frequency | 72 MHz |
| Program Flash | 256 KB (256K x 8) |
| SRAM | 64 KB |
| USB | USB 2.0 Full-Speed Device/Host/OTG |
| Pin Count | 44 |
| Package | QFN-44 (8x8 mm) |
| I/O Pins (max) | 35 |
| Analog Comparators | 3 |
| CTMU | Yes |
| RTCC | Yes |
| Operating Temperature | -40C to +85C (Industrial, I suffix) |
| Supply Voltage | 2.3 V to 3.6 V |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC32MX274F256D-I/ML Pin Configuration
| Pin 1 | RP15/RG15 — General I/O / remappable peripheral |
| Pin 2 | VDD — Supply voltage 2.3-3.6 V |
| Pin 3 | RP14/RG14 — General I/O / remappable peripheral |
| Pin 4 | RP13/SDA2/RG13 — I/O / I2C2 SDA |
| Pin 5 | RP12/SCL2/RG12 — I/O / I2C2 SCL |
| Pin 6 | RP11/RG11 — General I/O |
| Pin 7 | VSS — Ground |
| Pin 8 | RP10/RG10 — General I/O |
| Pin 9 | RP9/RG9 — General I/O |
| Pin 10 | RP8/RG8 — General I/O |
| Pin 11 | RP7/RG7 — General I/O |
| Pin 12 | RP6/RG6 — General I/O |
| Pin 13 | VSS — Ground |
| Pin 14 | VDD — Supply voltage 2.3-3.6 V |
| Pin 15 | RP5/RG5 — General I/O |
| Pin 16 | RP4/RG4 — General I/O |
| Pin 17 | RP3/RG3 — General I/O |
| Pin 18 | RP2/RG2 — General I/O |
| Pin 19 | RP1/RG1 — General I/O |
| Pin 20 | RP0/RG0 — General I/O |
| Pin 21 | VSS — Ground |
| Pin 22 | OSCI/RC12 — Oscillator input / general I/O |
| Pin 23 | OSCO/RC15 — Oscillator output / general I/O |
| Pin 24 | SOSCI/RPB4 — Secondary oscillator input / I/O |
| Pin 25 | SOSCO/RB4 — Secondary oscillator output / I/O |
| Pin 26 | VBUS — USB VBUS sense |
| Pin 27 | D- — USB D- differential data line |
| Pin 28 | D+ — USB D+ differential data line |
| Pin 29 | VUSB — USB 3.3 V regulator output / supply |
| Pin 30 | RA0 — Port A I/O |
| Pin 31 | RA1 — Port A I/O |
| Pin 32 | RA2 — Port A I/O |
| Pin 33 | RA3 — Port A I/O |
| Pin 34 | RA4 — Port A I/O |
| Pin 35 | RA5 — Port A I/O |
| Pin 36 | RA6 — Port A I/O |
| Pin 37 | RA7 — Port A I/O |
| Pin 38 | VSS — Ground |
| Pin 39 | VDD — Supply voltage 2.3-3.6 V |
| Pin 40 | RB0 — Port B I/O |
| Pin 41 | RB1 — Port B I/O |
| Pin 42 | RB2 — Port B I/O |
| Pin 43 | RB3 — Port B I/O |
| Pin 44 | EP — Exposed thermal pad - connect to ground |
Typical Applications
PIC32MX274F256D-I/ML is suitable for 7 applications: USB HID Peripherals (Keyboard, Mouse, Game Controller), Capacitive Touch User Interface, USB Audio Class Device, Low-Power Sensor Hub / IoT Edge Node, Industrial Control Front-End (PLC, HMI Panel), Segment LCD / Graphics Display Controller, Medical / Health Monitoring Peripheral.
USB HID Peripherals (Keyboard, Mouse, Game Controller)
The PIC32MX274F256D-I/ML is purpose-built for USB Human Interface Device peripherals thanks to its integrated USB 2.0 Full-Speed controller with on-chip transceiver, eliminating the need for an external PHY. The 72 MHz MIPS M4K core processes HID class drivers, NKRO scan matrices, and LED/PWM animations with ample headroom, while 64 KB SRAM accommodates HID report buffers plus USB stack RAM. The CTMU and 16-bit timers enable precise debounce and backlight PWM. Compared with older PIC32MX parts, the XLP sleep modes reduce suspend current to comply with USB 2.0 bus-powered suspend limits, and 35 I/O pins on QFN-44 support full-sized keyboards without an I/O extender.
Recommended
Capacitive Touch User Interface
The integrated Charge Time Measurement Unit (CTMU) and 16-bit timers make the PIC32MX274F256D-I/ML well suited for capacitive touch keypads, sliders, and proximity sensors. The CTMU provides sub-nanosecond current-source resolution for accurate capacitance measurement, while the 72 MHz MIPS M4K core runs Microchip's mTouch libraries in real time. Three analog comparators and 10-bit ADC enable mixed capacitive and resistive sensing on the same I/O. The 256 KB Flash stores mTouch firmware, gesture libraries, and user-configurable parameters, and the QFN-44 8x8 mm package fits in compact appliance and consumer front panels. XLP sleep current allows battery-powered touch remotes with months-long coin-cell life.
Recommended
USB Audio Class Device
Audio over USB requires deterministic isochronous transfer handling plus enough CPU to run sample-rate conversion. The PIC32MX274F256D-I/ML delivers 72 MHz MIPS M4K performance for 48 kHz / 16-bit USB Audio Class 1.0 streams, while 256 KB Flash stores the USB stack plus audio decoding, and 64 KB SRAM hosts ping-pong audio buffers. Hardware SPI/I2S ports connect to external DACs, and 16-bit timers generate MCLK/LRCK/BCLK with low jitter. The 44-pin QFN exposes up to 35 I/O for additional line/headphone switching and control. Designers porting from PIC32MX250/270 gain higher MIPS for the same power budget thanks to the XLP-efficient 27x core.
Recommended
Low-Power Sensor Hub / IoT Edge Node
The XLP ultra-low-power run/sleep/deep-sleep modes of the PIC32MX274F256D-I/ML make it suitable for battery-powered sensor hubs that wake on interrupt, sample, transmit over USB or UART, and return to deep sleep. The 72 MHz core handles on-board signal conditioning, while 64 KB SRAM buffers multi-sensor reads. The RTCC timestamps events during sleep, and the 10-bit ADC reads up to 1 Msps from analog sensors. The QFN-44 8x8 mm footprint with EP ground pad aids thermal performance in enclosed industrial enclosures. Compared with the PIC32MX270F256D, this part draws measurably less current in deep sleep, extending coin-cell and Li-Po battery life for IoT edge nodes.
Recommended
Industrial Control Front-End (PLC, HMI Panel)
The 72 MHz MIPS core, 44-pin QFN with 35 I/O, and rich analog peripherals (3 comparators, 10-bit ADC, RTCC) suit the PIC32MX274F256D-I/ML to industrial control front-ends, segment-LCD HMIs, and small PLC I/O modules. CTMU provides capacitive operator-panel sensing, and the USB port supports configuration upload and diagnostics over a mini-BMC receptacle. The -40C to +85C industrial temperature range (I suffix) handles factory floor conditions, and the XLP sleep modes fit sleep-current budgets for line-powered equipment in energy-saving states. 256 KB Flash stores IEC 61131-style logic plus communication stacks (RS-485, Modbus, USB CDC).
Recommended
Segment LCD / Graphics Display Controller
The Parallel Master Port (PMP) and 16-bit timers allow the PIC32MX274F256D-I/ML to drive segment-LCD glass or small TFT panels for graphics-based HMIs. The 256 KB Flash stores font tables and screen assets, and 64 KB SRAM is enough for small framebuffers. USB enables on-the-fly firmware update and screen asset download. The 72 MHz MIPS M4K core renders Microchip's graphics library objects (buttons, meters, animations) without offloading to external GPUs. Industrial temperature range suits appliance front panels and automotive aftermarket displays. The QFN-44 (8x8 mm) is footprint-compatible with the PIC32MX270F256D-I/ML for performance-tier upgrades.
Recommended
Medical / Health Monitoring Peripheral
Medical peripherals benefit from the PIC32MX274F256D-I/ML's USB CDC/HID connectivity, CTMU for accurate timing and capacitance-based measurement, and 16-bit timers for pulse-rate and respiration timing. The 72 MHz core runs sensor-fusion and BLE-over-USB bridging code, while 64 KB SRAM hosts sample buffers. XLP sleep modes extend battery life for portable patient monitors and wellness wearables, and the 44-pin QFN package fits compact form factors. Engineers should validate IEC 60601 compliance separately; this part's industrial -40C to +85C rating supports typical medical device environments when paired with proper isolation.
Recommended
Recommended Products Summary
Engineering reference data for PIC32MX274F256D-I/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC32MX270F256D-I/ML | PIC32MX250F256D-I/ML | PIC32MX230F256D-I/ML |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | QFN-44 (8x8 mm) | QFN-44 (8x8 mm) - same | QFN-44 (8x8 mm) - same | QFN-44 (8x8 mm) - same |
| Maximum CPU Frequency | 72 MHz | 72 MHz | 50 MHz | 50 MHz |
| Flash | 256 KB | 256 KB | 256 KB | 256 KB |
| SRAM | 64 KB | 64 KB | 64 KB | 64 KB |
| USB | USB 2.0 FS Device/Host/OTG | USB 2.0 FS Device/Host/OTG | USB 2.0 FS Device/Host/OTG | USB 2.0 FS Device/Host/OTG |
| XLP Ultra-Low Power | Yes (PIC32MX27x sub-family) | No | No | No |
| Industrial Temperature (-40C to +85C) | Yes (I suffix) | Yes | Yes | Yes |
| CTMU | Yes | Yes | Yes | Yes |
Key Differentiators
- 72 MHz core in the 28/44-pin XLP family with deep-sleep current reduction (vs PIC32MX270F256D-I/ML)
- Highest CPU frequency on a QFN-44 PIC32MX with 256 KB Flash (vs PIC32MX250F256D-I/ML)
- QFN-44 footprint reuse across three PIC32 generations (vs PIC32MX230F256D-I/ML)
Design Notes
Place a 10 uF bulk + 0.1 uF ceramic decoupling pair on each VDD/VSS pin pair of the QFN-44, with the 0.1 uF cap as close to the pin as possible. The PIC32MX274F256D's XLP run/sleep/deep-sleep currents depend on a clean supply; noisy rails will defeat the deep-sleep Iq spec. Use a ferrite bead on VBUS-derived USB supply to keep digital switching noise out of the analog reference, and bulk-decouple VUSB independently.
The QFN-44 (8x8 mm) has an exposed thermal pad on the bottom that MUST be soldered to a ground copper pour, not only for thermal dissipation but also for electrical reference. The 72 MHz MIPS M4K core dissipates measurable power at full speed, and a poor EP connection causes the internal die to overheat beyond the industrial +85C rating. Estimated: at 72 MHz, 3.3 V, full peripheral activity, typical core current is ~30 mA, dissipating ~100 mW - well within EP-handled range, but only with a proper ground pour.
Route USB D+ and D- as a 90-ohm differential pair, matched length within 150 mil, and keep them away from switching nodes or clock traces. Place the 0.1 uF VUSB bypass capacitor within 2 mm of the VUSB pin. For QFN-44 routing, fan out the inner-ring pins on both top and inner layers; the central EP pad needs multiple thermal vias (0.3 mm drill, 0.5 mm pitch) into the ground plane to keep junction temperature in range.
Do not confuse the /ML (QFN-44) suffix with /PT (TQFP-44), /SO (SOIC-28), /SP (SPDIP-28), or /MM (QFN-28). The PIC32MX274F256D family is also available in those packages but they are NOT drop-in replacements for the /ML footprint. Also note that the PIC32MX274F256D (XLP, 72 MHz) is a different sub-family from the PIC32MX274F256B (smaller pin count) - verify pin count before PCB layout.
Keep the SOSC 32.768 kHz crystal traces short and surrounded by ground guard; RTCC accuracy degrades with capacitive loading on SOSCI/SOSCO. Place decoupling capacitors on the same side as the IC for lowest ESL. For CTMU touch sensing, route the touch channels as short, guarded traces with a ground ring, and avoid crossing them with switching signals like PWM or USB data.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified - this part targets industrial -40C to +85C (I suffix) but is not automotive-grade; choose PIC32MX274F256D-V/ML (extended temperature) or PIC32MX274F256D-E/ML only if specific automotive compliance is required.
