PIC32MX270F256B-I/SS - 32-bit 40MHz MCU, 256KB Flash | Microchip
MPN: PIC32MX270F256B-I/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.4 | $5.40 |
| 10 | $4.86 | $48.60 |
| 100 | $4.32 | $432.00 |
| 500 | $3.83 | $1,915.00 |
| 1,000 | $3.4 | $3,400.00 |
PIC32MX270F256B-I/SS Overview
A microcontroller (MCU) is an integrated circuit combining a CPU core, RAM, non-volatile program memory, and configurable peripherals (ADC, timers, communication interfaces) on a single die. The PIC32MX270 family belongs to the broader 32-bit MCU category, which sits hierarchically above 8/16-bit MCUs and below microprocessor units (MPUs). It enables embedded developers to build standalone products with deterministic firmware execution and rich analog/digital peripherals.
Key features of this variant include 0.5 mA/MHz typical active current consumption, support for mTouch capacitive touch buttons and sliders, a high-resolution 1 ns time measurement module, an on-chip temperature sensor, and a 10-bit ADC. The PPS subsystem lets signals be remapped to multiple pins, simplifying PCB layout and BOM changes late in the design cycle.
The PIC32MX270 architecture uses a 5-stage pipeline MIPS32 M4K core with hardware multiply/divide and a single-cycle Flash read path, achieving 83 DMIPS at full 40 MHz clock. Integrated Full-Speed USB 2.0 OTG with on-chip transceiver, CAN 2.0B, I2S, PMP for direct graphics display connection, and 16-bit Parallel Master Port make it suitable for human-machine interface designs without external bus controllers.
Typical applications include USB audio peripherals, capacitive touch human-interface devices, low-cost graphics terminals using PMP, industrial control with CAN bus connectivity, and battery-powered IoT edge nodes with USB charging.
When designing with this part, note that the SSOP package's thermal dissipation capability is limited. Use adequate copper pour for thermal relief, place decoupling capacitors close to VDD/VSS pairs, and ensure the ICSP programming pins are accessible. Program/debug with MPLAB X IDE, MPLAB XC32 compiler, and a PICkit3/Snap programmer-debugger.
This page synthesizes Microchip datasheet specifications, current distributor pricing from DigiKey and Mouser, drop-in SSOP alternatives from the PIC32MX family, and practical design notes beyond the manufacturer datasheet.
Drop-in alternatives for PIC32MX270F256B-I/SS — 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 PIC32MX270F256B-I/SS (same form factor and footprint) — differing in Package, ADC, Operating Temperature, SRAM, MSL Level.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC32MX270F256BT-I/SS
✅ Drop-In✓ In Stock
$3.89 / Unit
View Datasheet →PIC32MX270F128B-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX230F256B-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC32MX130F256B-I/SS
✅ Drop-In✓ In Stock
$3.15 / Unit
View Datasheet →PIC32MX150F128B-I/SS
✅ Drop-In✓ In Stock
$2.65 / Unit
View Datasheet →PIC32MX270F256B-I/SS Maximum Ratings & Electrical Characteristics
| Core | MIPS32 M4K 32-bit RISC |
| Core Frequency | 40 MHz (up to 50 MHz/83 DMIPS) |
| Program Flash Memory | 256 KB (256K x 8) |
| SRAM | 64 KB |
| Package | 28-SSOP (0.209" / 5.30 mm body width) |
| Operating Voltage | 2.3 V to 3.6 V |
| Operating Temperature | -40 C to +85 C (industrial) |
| Active Current | 0.5 mA/MHz (typical) |
| ADC | 10-bit, multi-channel |
| USB | Full-Speed USB 2.0 OTG with on-chip transceiver |
| Connectivity | I2C, IrDA, LIN, SPI, UART/USART, USB OTG |
| Special Peripherals | I2S, PMP, PPS, mTouch, 16-bit timers, 1 ns time measurement, RTCC |
| Peripheral Pin Select (PPS) | Yes |
| Parallel Master Port (PMP) | Yes |
| On-chip Temperature Sensor | Yes |
| RoHS Status | Compliant |
| MSL Level | 1 (unlimited floor life) |
PIC32MX270F256B-I/SS Pin Configuration
| Pin 1 | MCLR — Master Clear (Reset) input. Connect to VDD via 10 kOhm pull-up. |
| Pin 2 | PGED1/AN0/CVD7/RPB0/PMD0/RA0 — Programming/Data, Analog Input, CVD Touch, I/O. |
| Pin 3 | PGEC1/AN1/CVD8/RPB1/PMD1/RA1 — Programming/Clock, Analog Input, CVD Touch, I/O. |
| Pin 4 | PGED2/AN2/CVD9/RPB2/PMD2/RA2 — Programming/Data 2, Analog Input, I/O. |
| Pin 5 | PGEC2/AN3/CVD10/RPB3/PMD3/RA3 — Programming/Clock 2, Analog Input, I/O. |
| Pin 6 | VDD — Positive supply voltage (2.3 V to 3.6 V). |
| Pin 7 | VSS — Ground reference. |
| Pin 8 | CVDRP/RPC0/PMA0/RA10 — CVD Reference, I/O. |
| Pin 9 | CVDTX/PMA2/RA11 — CVD Transmit, I/O. |
| Pin 10 | RPC1/OSC2/PMA3/RA12 — Oscillator output, I/O. |
| Pin 11 | RPC2/CLKO/PMA4/RA13 — I/O, peripheral clock output. |
| Pin 12 | RPC3/PMA5/RA14 — I/O. |
| Pin 13 | RPC4/PMA6/RA15 — I/O. |
| Pin 14 | VDD — Positive supply voltage. |
| Pin 15 | VSS — Ground reference. |
| Pin 16 | AN4/CVD0/RPB4/PMD4/RA4 — Analog Input, CVD Touch, I/O. |
| Pin 17 | AN5/CVD1/RPB5/PMD5/RA5 — Analog Input, CVD Touch, I/O. |
| Pin 18 | AN6/CVD2/RPB6/PMD6/RA6 — Analog Input, CVD Touch, I/O. |
| Pin 19 | AN7/CVD3/RPB7/PMD7/RA7 — Analog Input, CVD Touch, I/O. |
| Pin 20 | AN8/CVD4/RPB8/PMD8/RA8 — Analog Input, CVD Touch, I/O. |
| Pin 21 | VSS — Ground reference. |
| Pin 22 | VDD — Positive supply voltage. |
| Pin 23 | AN9/CVD5/RPB9/PMD9/RA9 — Analog Input, CVD Touch, I/O. |
| Pin 24 | CVDRP/CVD11/RPB10/PMD10/RPB10 — CVD Reference, I/O. |
| Pin 25 | AN10/CVD12/RPB11/PMD11/RPB11 — Analog Input, CVD Touch, I/O. |
| Pin 26 | AN11/CVD13/RPB12/PMD12/RPB12 — Analog Input, CVD Touch, I/O. |
| Pin 27 | CVDRP/CVD14/RPB13/PMD13/RPB13 — CVD Reference, I/O. |
| Pin 28 | AN12/CVD15/RPB14/PMD14/RPB14 — Analog Input, CVD Touch, I/O. |
Typical Applications
PIC32MX270F256B-I/SS is suitable for 6 applications: USB Audio Peripheral (Headset / DAC Interface), Capacitive Touch Human-Interface Device, Low-Cost Graphics Terminal (PMP Display), Industrial CAN Node / Sensor Hub, Battery-Powered IoT Edge Node, USB Barcode / Magnetic-Stripe Reader.
USB Audio Peripheral (Headset / DAC Interface)
The PIC32MX270F256B-I/SS is a strong fit for USB audio peripherals such as USB headphones, USB DACs, and USB microphones because of its integrated Full-Speed USB 2.0 OTG with on-chip transceiver and dual I2S/SPI modules for codec interfacing. With 256 KB Flash and 64 KB SRAM it runs USB audio class 1.0 device firmware up to 96 kHz / 24-bit plus a custom DSP filter chain. Place the device on a 3.3 V rail with decoupling close to VDD/VSS pairs and route D+/D- as a 90 ohm impedance USB 2.0 differential pair. The integrated PHY removes the need for an external USB transceiver, reducing BOM and PCB area versus discrete MCU + external PHY designs.
Recommended
Capacitive Touch Human-Interface Device
The PIC32MX270F256B-I/SS is ideal for capacitive touch human-interface devices including touch buttons, sliders, and proximity sensors, thanks to its built-in mTouch capacitive touch library support and on-chip temperature sensor. The Peripheral Pin Select (PPS) subsystem lets touch channels be remapped to nearly any I/O pin, simplifying PCB layout when buttons are added or relocated. The 256 KB program Flash stores touch libraries, gesture decoding, and connectivity stacks. Charge current at 0.5 mA/MHz lets battery-powered touch devices achieve weeks of standby by duty-cycling the touch scan loop.
Recommended
Low-Cost Graphics Terminal (PMP Display)
The PIC32MX270F256B-I/SS fits low-cost graphics terminals using its Parallel Master Port (PMP) interface to drive small TFT or OLED displays directly without an external graphics controller. PMP supports 8/16-bit data plus dedicated control signals to displays up to QVGA resolution, while the 64 KB SRAM holds frame buffers and font tables. Compared to designs requiring an external display controller, the integrated PMP cuts BOM cost and PCB area. Designers can use Microchip's MPLAB Harmony graphics library for rapid prototyping and run display refresh plus USB touch input on the same 40 MHz MIPS32 M4K core.
Recommended
Industrial CAN Node / Sensor Hub
The PIC32MX270F256B-I/SS is well suited as an industrial CAN 2.0B sensor node because it integrates CAN hardware and the 256 KB Flash stores CANopen or DeviceNet protocol stacks plus application code. The on-chip 10-bit ADC reads sensor signals while CAN bus interfaces the network. Industrial temperature grade (-40 C to +85 C) lets it operate in factory automation cabinets. Pair the MCU with an external CAN transceiver such as the MCP2552 I/O for bus-level signaling. The integrated 1 ns time measurement module supports precise event timestamping for distributed control loops.
Recommended
Battery-Powered IoT Edge Node
The PIC32MX270F256B-I/SS is a good fit for battery-powered IoT edge nodes thanks to its 0.5 mA/MHz active current consumption and sub-microamp sleep modes with full 64 KB SRAM retention. The on-chip temperature sensor plus 10-bit ADC read environmental sensors, while UART/SPI ports interface external radios such as Sub-GHz transceivers. The Peripheral Pin Select (PPS) routes radio interrupts to any pin, simplifying PCB layout. Designers can duty-cycle the MCU for sub-1 mA average consumption, extending coin-cell battery life to months in low-duty applications.
Recommended
USB Barcode / Magnetic-Stripe Reader
The PIC32MX270F256B-I/SS suits USB barcode or magnetic-stripe readers thanks to its integrated USB device controller and 64 KB SRAM for HID class firmware plus decoding buffers. Designers implement USB HID keyboard or vendor-specific class firmware to host PCs without installing drivers on modern operating systems. The 256 KB Flash supports scanner decoding libraries and USB stacks. Place the MCU near the USB-C connector, route D+/D- as a 90 ohm differential pair, and add ESD protection on the USB data lines. Same MCU can drive a small OLED via I2C plus a buzzer via PWM for the user feedback.
Recommended
Recommended Products Summary
Engineering reference data for PIC32MX270F256B-I/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC32MX270F256BT-I/SS | PIC32MX270F128B-I/SS | PIC32MX230F256B-I/SS | PIC32MX130F256B-I/SS | PIC32MX150F128B-I/SS |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SSOP | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same |
| Core | MIPS32 M4K 32-bit | MIPS32 M4K 32-bit - same | MIPS32 M4K 32-bit - same | MIPS32 M4K 32-bit - same | MIPS32 M4K 32-bit - same | MIPS32 M4K 32-bit - same |
| Clock Speed | 40 MHz (50 MHz max) | 40 MHz - same | 40 MHz - same | 40 MHz - same | 40 MHz - same | 40 MHz - same |
| Flash | 256 KB | 256 KB - same | 128 KB (-50%) | 256 KB - same | 256 KB - same | 128 KB (-50%) |
| SRAM | 64 KB | 64 KB - same | 64 KB - same | 64 KB - same | 64 KB - same | 32 KB (-50%) |
| USB OTG | Full-Speed with on-chip transceiver | Full-Speed with on-chip transceiver | Full-Speed with on-chip transceiver | Not present | Not present | Not present |
| CAN 2.0B | Yes | Yes | Yes | Not present | Not present | Not present |
| PMP | Yes | Yes | Yes | Yes | Yes | Yes |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
Key Differentiators
- Full-Speed USB 2.0 OTG with integrated PHY transceiver (vs PIC32MX230F256B-I/SS)
- Higher Flash density with same package (vs PIC32MX270F128B-I/SS)
- CAN 2.0B for industrial networking (vs PIC32MX130F256B-I/SS)
Design Notes
Decouple every VDD/VSS pair on the PIC32MX270F256B-I/SS with a 100 nF ceramic capacitor placed within 1-3 mm of each VDD pin, plus a bulk 4.7 uF to 10 uF tantalum or ceramic capacitor at the device supply. The MCU can glitch at 0.5 mA/MHz during active operation; insufficient bulk causes supply droop during core or USB transitions. For USB bus-powered designs, add a ferrite bead between the VBUS-derived 3.3 V regulator output and the VDD pins.
Ensure the MCLR pin (pin 1) is pulled up to VDD via a 10 kOhm resistor and has a 0.01 uF to 0.1 uF capacitor to VSS for noise immunity; an open or floating MCLR causes intermittent resets. The ICSP programming pins PGED1/PGEC1 (or PGED2/PGEC2) must be accessible for in-circuit programming. If unused I/O pins can float, configure them as outputs or enable internal pull-ups to avoid phantom interrupts.
Route USB D+ and D- on the PIC32MX270F256B-I/SS as a 90 ohm differential pair with continuous reference plane on the layer immediately below. The on-chip transceiver is rated for Full-Speed USB 2.0 only; do not exceed 12 Mbps. Add ESD protection (such as USBLC6-2SC6) near the USB connector to protect the MCU's VDD/USB pins from ESD strikes during cable insertion. Keep trace length matched within 150 mil.
The 28-SSOP package's 0.65 mm pitch requires careful PCB design: use 0.4 mm drill / 0.20 mm annular ring if your PCB fab supports it, and apply solder mask defined (SMD) pads rather than non-solder mask defined (NSMD) to reduce solder joint stress in thermal cycling. Provide a copper pour under the SSOP body for thermal relief and to lower ground impedance. The exposed pad is not present on SSOP-28, but a small copper area under the body improves thermal performance by a few percent.
Estimated: at 40 MHz active operation and 0.5 mA/MHz typical current, the PIC32MX270F256B-I/SS consumes ~20 mA plus peripheral current at 3.3 V. Power dissipation is approximately 66 mW, which is well below the SSOP-28 thermal limit of roughly 1000 mW. No external heatsink is required. In enclosed industrial enclosures above 60 C ambient, ensure adequate copper pours above to keep junction temperature rise modest.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified - choose AEC-Q100 qualified PIC32 variants for automotive use. Lead-free and halogen-free migration in industrial temp grade.
