PIC32MX274F256B-V/SO - 32-bit MCU, 256KB Flash, USB, AEC-Q100 | Microchip
MPN: PIC32MX274F256B-V/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.85 | $6.85 |
| 10 | $6.17 | $61.70 |
| 100 | $5.48 | $548.00 |
| 500 | $4.93 | $2,465.00 |
| 1,000 | $4.41 | $4,410.00 |
PIC32MX274F256B-V/SO Overview
A 32-bit microcontroller (MCU) is an integrated circuit that combines a 32-bit processor core, program memory, data memory, and a rich set of peripherals on a single die. PIC32MX devices belong to the broader PIC32 family (MIPS32 architecture), which itself sits within the wider category of microcontrollers (MCUs), embedded processors, semiconductors, and integrated circuits. PIC32MX270/274 parts are positioned as low-power (XLP) general-purpose MCUs targeting USB-enabled consumer, industrial, and automotive designs.
Key features include a maximum CPU clock of 72 MHz with 83 DMIPS core performance, two I2C, two SPI, and four UART (with RS-485/IrDA support) peripherals, a 10-bit 1 Msps Analog-to-Digital Converter (ADC) with up to 13 input channels, three analog comparators, a Real-Time Clock and Calendar (RTCC), and a Charge Time Measurement Unit (CTMU) for capacitive touch and precise time measurement. The device operates from 2.3 V to 3.6 V across the -40 C to +105 C automotive temperature range.
Architecturally, the PIC32MX274F256B integrates a MIPS32 M4K core with 5-stage pipeline and hardware multiply/divide, separate 16 KB I-cache and 4 KB D-cache, a 4-channel DMA controller for low-overhead peripheral data movement, and a peripheral bus (PBUS) that decouples I/O timing from the CPU clock. The on-chip Full-Speed USB 2.0 controller includes an internal transceiver and on-chip pull-up resistors, allowing direct USB device/host/OTG connection with minimal external components.
Typical applications include automotive body electronics, USB human-interface devices (keyboards, mice, touch panels), industrial sensor hubs, portable data loggers, low-power consumer devices, and capacitive-touch user interfaces using the on-chip CTMU. The XLP (eXtreme Low Power) features (down to sub-microamp sleep currents) make it well-suited to battery-powered and always-on applications.
When designing with this MCU, ensure the 28-pin SOIC layout reserves proper decoupling (one 0.1 uF X7R per VDD pair plus a bulk 10 uF), keeps the 48 MHz secondary oscillator traces short, and uses Microchip's MPLAB X IDE with Harmony or MCC code configurators to shorten firmware development. Always validate the USB differential pair impedance per USB 2.0 FS requirements.
This page synthesizes distributor pricing, drop-in alternative part numbers, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC32MX274F256B-V/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 PIC32MX274F256B-V/SO (same form factor and footprint) — differing in ADC, Package, Timers, Core Architecture, Maximum CPU Frequency.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC32MX274F256B-I/SO
✅ Drop-In✓ In Stock
$4.35 / Unit
View Datasheet →PIC32MX270F256B-V/SO
✅ Drop-In✓ In Stock
$5.2 / Unit
View Datasheet →PIC32MX274F256BT-V/SO
✅ Drop-In✓ In Stock
$4.13 / Unit
View Datasheet →PIC32MX274F128B-V/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX274F256B-V/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX274F256B-I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX270F256D-V/ML
✅ Drop-In✓ In Stock
$4.05 / Unit
View Datasheet →PIC32MX274F256B-V/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | MIPS32 M4K |
| Core Width | 32-bit |
| Max CPU Clock | 72 MHz |
| Performance | 83 DMIPS |
| Program Flash Memory | 256 KB |
| SRAM | 64 KB |
| Operating Voltage Range | 2.3 V to 3.6 V |
| USB Controller | Full-Speed USB 2.0 with on-chip transceiver |
| I2C | 2 |
| SPI | 2 |
| UART | 4 (RS-485/IrDA support) |
| ADC | 10-bit, up to 13 input channels, 1 Msps |
| Comparators | 3 |
| RTCC | Yes |
| CTMU | Yes |
| DMA | 4 channels |
| I-Cache / D-Cache | 16 KB / 4 KB |
| Operating Temperature Range | -40 C to +105 C (Automotive, -V grade) |
| Package | 28-pin SOIC (SO) |
| AEC-Q100 Qualification | Yes (Automotive grade) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC32MX274F256B-V/SO Pin Configuration
| Pin 1 | SDA2/RG3 — I2C2 data / Port G bit 3 (multi-function) |
| Pin 2 | SCL2/RG2 — I2C2 clock / Port G bit 2 (multi-function) |
| Pin 3 | CVREF/AN1/C1INC/C2INC/RB0 — Comparator voltage reference / ADC input / Port B bit 0 |
| Pin 4 | AN2/C1IND/C2IND/C3IND/RTCC/RB1 — ADC input / RTCC / Port B bit 1 |
| Pin 5 | AN3/C1INC/C2INC/C3INC/CTED1/RB2 — ADC input / CTMU edge / Port B bit 2 |
| Pin 6 | AN4/C1OUT/C2OUT/C3OUT/CTED2/RB3 — ADC input / Comparator output / CTMU edge / Port B bit 3 |
| Pin 7 | VDD — Positive supply (3.3 V) |
| Pin 8 | VSS — Ground |
| Pin 9 | PGEC1/AN5/RB4 — ICSP clock / ADC input / Port B bit 4 |
| Pin 10 | PGED1/AN6/RB5 — ICSP data / ADC input / Port B bit 5 |
| Pin 11 | PGEC2/AN7/RB6 — ICSP clock 2 / ADC input / Port B bit 6 |
| Pin 12 | PGED2/AN8/RB7 — ICSP data 2 / ADC input / Port B bit 7 |
| Pin 13 | AN9/C2INC/C3INC/RB8 — ADC input / Port B bit 8 |
| Pin 14 | VSS — Ground |
| Pin 15 | OC1/IC1/RB9 — Output compare 1 / Input capture 1 / Port B bit 9 |
| Pin 16 | OC2/IC2/RA0 — Output compare 2 / Input capture 2 / Port A bit 0 |
| Pin 17 | VUSB/VBUS — USB transceiver supply / VBUS sense |
| Pin 18 | VDD — Positive supply (3.3 V) |
| Pin 19 | VSS — Ground |
| Pin 20 | D+/RG0 — USB D+ / Port G bit 0 |
| Pin 21 | D-/RG1 — USB D- / Port G bit 1 |
| Pin 22 | U1RXR/U1TX/RF8 — UART1 TX / Port F bit 8 |
| Pin 23 | U1RX/SDO1/RF2 — UART1 RX / SPI1 SDO / Port F bit 2 |
| Pin 24 | SCK1/RF6 — SPI1 clock / Port F bit 6 |
| Pin 25 | SDI1/RF7 — SPI1 SDI / Port F bit 7 |
| Pin 26 | OC3/RA1 — Output compare 3 / Port A bit 1 |
| Pin 27 | OC4/RA2 — Output compare 4 / Port A bit 2 |
| Pin 28 | OSC1/CLKI/RC12 — Crystal oscillator input / Port C bit 12 |
Typical Applications
PIC32MX274F256B-V/SO is suitable for 6 applications: Automotive Body Electronics, USB Human-Interface Devices (HID), Capacitive Touch User Interfaces, Industrial Sensor Hubs, Low-Power Data Loggers, Audio Interface and Consumer DAC Controls.
Automotive Body Electronics
The PIC32MX274F256B-V/SO is a strong fit for automotive body modules such as HVAC controllers, instrument-cluster sub-controllers, and lighting nodes, where its AEC-Q100 qualification (-40 C to +105 C) and 256 KB of Flash comfortably host CAN-style state machines, RTCC-driven scheduling, and bootloader stacks. Its 72 MHz MIPS32 M4K core delivers 83 DMIPS, sufficient for sensor-fusion loops at sub-10 ms latency while leaving headroom for diagnostics. The 28-pin SOIC package is widely accepted by automotive Tier-1 SMT lines and supports the IR-reflow profiles required for AEC-Q100 assembly. Pair this MCU with a CAN transceiver such as the MCP2515 (SPI-attached) or MCP25625 (high-speed CAN) to form a complete body-domain node; an external watchdog such as the MCP1316 further hardens the design against automotive EMC transients.
Recommended
USB Human-Interface Devices (HID)
On-board Full-Speed USB 2.0 with an integrated transceiver makes the PIC32MX274F256B-V/SO ideal for USB keyboards, mice, touch panels, barcode scanners, and custom HID peripherals that stream data over USB without an external PHY. The 83 DMIPS CPU performance comfortably handles USB polling, debouncing, and HID report composition at 1 kHz rates, while the 64 KB SRAM accommodates dual buffers and report descriptors. The CTMU enables precise capacitive touch sensing on the same MCU, eliminating a separate touch controller in many designs. Use Microchip's MPLAB Harmony USB stack or the MLA USB framework for HID class compliance, and pair with a low-dropout regulator such as the MCP1825 to deliver clean 3.3 V to the VDD pins.
Recommended
Capacitive Touch User Interfaces
The on-chip Charge Time Measurement Unit (CTMU) combined with the 10-bit ADC allows the PIC32MX274F256B-V/SO to implement up to 13 self-capacitive or mutual-capacitive touch channels for sliders, wheels, and matrix keypads. Sub-microamp sleep currents from the XLP architecture let the MCU wake on a touch event and return to sleep, enabling battery-powered remote controls and sealed-touch appliances. The 72 MHz core is more than adequate to debounce and report touches within 10 ms, and 256 KB Flash comfortably hosts Microchip's mTouch library plus application firmware. Pair with a dedicated touch tuning capacitor network and a low-leakage LDO regulator; in industrial designs, the industrial-grade PIC32MX274F256B-I/SO can substitute without changing firmware.
Recommended
Industrial Sensor Hubs
The PIC32MX274F256B-V/SO operates as a sensor hub aggregating inputs from I2C/SPI sensors (temperature, pressure, accelerometers) and exposing them over USB, UART, or RS-485. Its four UARTs with built-in RS-485 support and two independent I2C/SPI channels allow a multi-master sensor network without additional bus switches, while the 4-channel DMA engine keeps CPU load low even at high sampling rates. The 256 KB Flash fits protocol stacks such as Modbus RTU, while the 64 KB SRAM buffers aggregated sensor frames before transmission. The automotive AEC-Q100 grade also makes it acceptable for industrial cabinets, where wide temperature margins simplify enclosure thermal design. Pair with a TVS-protected RS-485 transceiver such as the ISL3179 for robust industrial bus connectivity.
Recommended
Low-Power Data Loggers
The XLP (eXtreme Low Power) features of the PIC32MX274F256B-V/SO deliver nanoamp-range deep-sleep currents, making the MCU suitable for battery- or solar-powered remote data loggers that wake periodically, take ADC readings, store to internal Flash or external EEPROM, and return to sleep. The 10-bit 1 Msps ADC with up to 13 channels can sample multiple analog sensors per wake cycle, and the RTCC provides time-stamped events with seconds-to-years resolution. 256 KB of Flash provides ample space for circular log buffers and wear-leveling firmware. For battery applications, the industrial variant PIC32MX274F256B-I/SO provides identical low-power behaviour at lower cost when AEC-Q100 is not required.
Recommended
Audio Interface and Consumer DAC Controls
The four UARTs, two I2C, and two SPI controllers of the PIC32MX274F256B-V/SO make it a capable controller for consumer audio interfaces such as volume knobs, source selectors, and Bluetooth audio module bridges (e.g., BM64/BM83 modules via UART). The CTMU provides smooth-touch volume sliders, while the 256 KB Flash stores preset tables and DSP control surfaces. The AEC-Q100 automotive grade also makes it appropriate for in-car infotainment keypads. Use the PIC32MX274F256B-I/SO industrial variant for home audio to optimize BOM cost.
Recommended
Recommended Products Summary
Engineering reference data for PIC32MX274F256B-V/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC32MX274F256B-I/SO | PIC32MX270F256B-V/SO | PIC32MX274F256BT-V/SO | PIC32MX274F128B-V/SO |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin SOIC | 28-pin SOIC - same | 28-pin SOIC - same | 28-pin SOIC - same | 28-pin SOIC - same |
| Max CPU Clock | 72 MHz | 72 MHz | 50 MHz | 72 MHz | 72 MHz |
| Flash | 256 KB | 256 KB | 256 KB | 256 KB | 128 KB |
| SRAM | 64 KB | 64 KB | 64 KB | 64 KB | 64 KB |
| Temperature Grade | Automotive -40C to +105C | Industrial -40C to +85C | Automotive -40C to +105C | Automotive -40C to +105C | Automotive -40C to +105C |
| AEC-Q100 Qualified | Yes | No | Yes | Yes | Yes |
| USB 2.0 FS | Yes (on-chip transceiver) | Yes (on-chip transceiver) | Yes (on-chip transceiver) | Yes (on-chip transceiver) | Yes (on-chip transceiver) |
Key Differentiators
- Highest 72 MHz clock in the PIC32MX2 family 28-pin SOIC (vs PIC32MX270F256B-V/SO)
- AEC-Q100 automotive temperature grade on SOIC package (vs PIC32MX274F256B-I/SO)
- 256 KB Flash vs 128 KB Flash (vs PIC32MX274F128B-V/SO)
Design Notes
Place a 0.1 uF X7R decoupling capacitor within 3 mm of every VDD/VSS pin pair on the 28-pin SOIC (pins 7-8, 14, 18-19) plus one 10 uF bulk ceramic near pin 7. The internal 1.8 V core regulator needs a stable 3.3 V input; ripple above 50 mVpk on VDD can cause PLL jitter and USB enumeration failures. The USB VBUS pin (pin 17) should be tied to VDD through a 4.7 kohm resistor or driven by VBUS directly through a 10 kohm divider per the USB device tree design rules.
Route the USB D+ (RG0, pin 20) and D- (RG1, pin 21) traces as a 90-ohm differential pair with matched lengths and continuous ground reference, as required by USB 2.0 Full-Speed. Keep the pair length under 50 mm if possible, and avoid stubs or right-angle bends. Place the ESD protection array (such as the USBLC6-2SC6) within 3 mm of the USB connector, with the ground paddle tied directly to the VSS pour.
Do not assume pin-function compatibility across the PIC32MX1, PIC32MX2, and PIC32MX27x sub-families - while the 28-pin SOIC pinout is identical between the 270 and 274, peripheral remap registers differ. Do not populate both PGEC1/PGED1 (pins 9-10) and PGEC2/PGED2 (pins 11-12) for ICSP simultaneously - use one pair per programming tool. For AEC-Q100 layouts, follow IPC-7530A thermal profile guidelines and avoid placing thermal reliefs on QFP/QFN ground pads that would degrade heat dissipation.
Compliance Information
AEC-Q100 qualified per the automotive -V suffix; RoHS and lead-free confirmed by distributor listings. Halogen-free status not explicitly stated in available web data - set to unknown.
