PIC32MX270F256BT-I/SO - 256KB Flash 40MHz 32-bit MCU | Microchip
MPN： PIC32MX270F256BT-I/SO ✓ 啟用中PIC32MX270F256BT-I/SO 概覽
A 32-bit microcontroller is a microprocessor with on-chip Flash program memory, SRAM, and peripherals sized for embedded control. PIC32MX2XX parts scale the MIPS32 M4K core up to 256 KB Flash and 64 KB SRAM while adding Peripheral Pin Select (PPS) for flexible pin remapping, multiple DMA channels, and separate PLLs for the CPU and USB clocks. Within the broader product hierarchy, a PIC32MX MCU sits below general-purpose 32-bit MCUs but above 8-bit PIC16/PIC18 parts in compute, memory, and peripheral integration. The PIC32MX270F256BT-I/SO is one of the higher-density variants in this family.
Key features include hardware DMA with automatic data size detection, an on-chip temperature measurement diode with 1 ns high-resolution time-measurement capability, mTouch capacitive-touch support, an integrated Real-Time Clock (RTCC) with calendar, and configurable Watchdog Timer with on-chip Low-Power RC oscillator. The 28-pin SOIC package allows hand-soldering and breadboarding for prototype work, while the same die is also offered in QFN-28, QFN-36, and 44-pin variants for layout flexibility.
Typical applications include USB HID peripherals (keyboards, mice, game controllers), capacitive-touch user interfaces, audio playback devices, low-resolution graphics with PMP-driven TFT panels, and industrial sensor hubs requiring deterministic USB connectivity. The combination of USB 2.0 FS OTG, mTouch, and PMP in a 28-pin package makes the part well suited for cost-sensitive consumer and industrial HMI products.
When designing with this MCU, follow the datasheet guidance on decoupling (typically 0.1 uF and 10 uF near each power pin) and ensure the USB VUSB pin has the correct 3.3V rail conditioning. The PPS peripheral mapping lets the designer reassign digital peripherals to alternative I/O pins, which simplifies PCB routing when remapping UART, SPI, or I2C channels is needed late in development.
直接替換替代品，適用於 PIC32MX270F256BT-I/SO — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： PIC32MX270F256BT-I/SO （相同外形與佔位） — 差異在於 ADC, Package, DMA Channels, Operating Temperature, USB.
PIC32MX270F256B-I/SO
✅ 直接替換聯絡詢價
查看資料表 →PIC32MX170F256BT-I/SO
✅ 直接替換聯絡詢價
查看資料表 →PIC32MX250F256BT-I/SO
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
PIC32MX254F128BT-I/SO
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →PIC32MX150F128BT-I/SO
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →PIC32MX270F256BT-I/SO 最大額定值與電氣特性
| Core Architecture | MIPS32 M4K |
| Core Frequency | 40 MHz (50 MHz extended) |
| DMIPS Performance | 83 DMIPS |
| Program Flash | 256 KB |
| SRAM | 64 KB |
| Operating Voltage | 2.3 V to 3.6 V |
| Active Current | 0.5 mA/MHz (typical) |
| 工作溫度 | -40C to +85C (Industrial) |
| ADC | 10-bit, up to 1.28 Msps |
| USB | USB 2.0 Full-Speed OTG |
| UART | 2 |
| I2C | 2 |
| SPI / I2S | 2 (SPI with I2S mode) |
| DMA Channels | Up to 4 with auto data-size detection |
| Parallel Master Port (PMP) | Yes |
| Peripheral Pin Select (PPS) | Yes |
| mTouch Capacitive Touch | Yes |
| RTCC | Yes (calendar/alarm) |
| Watchdog Timer | Yes, with on-chip LPRC oscillator |
| PLL | Separate PLLs for CPU and USB |
| On-chip Temperature Sensor | Yes |
| 封裝 | 28-SOIC (7.50 mm body width) |
| 安裝類型 | Surface Mount |
| RoHS 狀態 | Compliant |
| Packaging Form | Tape & Reel ("BT" suffix) |
PIC32MX270F256BT-I/SO 腳位配置
| 腳位 1 | MCLR — Master Clear (reset) input, active-low |
| 腳位 2 | PGED1/AN0/CVD1/RPB0 — Programming data / Analog input 0 / CVD cap touch |
| 腳位 3 | PGEC1/AN1/CVD2/RPB1 — Programming clock / Analog input 1 / CVD cap touch |
| 腳位 4 | AN2/CVD3/RPB2 — Analog input 2 / CVD cap touch |
| 腳位 5 | AN3/CVD4/RPB3 — Analog input 3 / CVD cap touch |
| 腳位 6 | VDD — Positive supply for I/O logic |
| 腳位 7 | VSS — Ground reference for I/O logic |
| 腳位 8 | AN4/RPB4 — Analog input 4 |
| 腳位 9 | AN5/RPB5 — Analog input 5 |
| 腳位 10 | VREF+/CVREF+/AN6+ — ADC voltage reference positive |
| 腳位 11 | VREF-/CVREF-/AN7- — ADC voltage reference negative |
| 腳位 12 | AN8/RPB8 — Analog input 8 |
| 腳位 13 | AN9/RPB9 — Analog input 9 |
| 腳位 14 | AN10/RPB10 — Analog input 10 |
| 腳位 15 | AN11/RPB11 — Analog input 11 |
| 腳位 16 | VSS — Ground reference for core logic |
| 腳位 17 | VDD — Positive supply for core logic |
| 腳位 18 | PGED2/RPB12 — Programming data alternate / GPIO |
| 腳位 19 | PGEC2/RPB13 — Programming clock alternate / GPIO |
| 腳位 20 | AN12/RPB14 — Analog input 12 |
| 腳位 21 | AN13/RPB15 — Analog input 13 |
| 腳位 22 | VUSB3V3 — USB internal transceiver 3.3V supply |
| 腳位 23 | D+/RB6 — USB D+ data line |
| 腳位 24 | D-/RB7 — USB D- data line |
| 腳位 25 | OSCI/RPC6 — Crystal oscillator input |
| 腳位 26 | OSCO/RPC7 — Crystal oscillator output |
| 腳位 27 | SOSCI/RPC8 — Secondary oscillator input (RTCC) |
| 腳位 28 | SOSCO/RPC9 — Secondary oscillator output (RTCC) |
典型應用
PIC32MX270F256BT-I/SO 適用於 6 應用s: USB HID Peripherals (Keyboards, Mice, Gamepads), Capacitive Touch User Interfaces (mTouch), Audio Playback Devices (I2S Codec Interface), Low-Resolution Graphics (PMP-driven TFT), Industrial Sensor Hubs with USB Diagnostics, Home Automation and IoT Edge Devices.
USB HID Peripherals (Keyboards, Mice, Gamepads)
The PIC32MX270F256BT-I/SO is purpose-built for USB HID applications including USB keyboards, mice, HID-class gamepads, and custom HID peripherals. Its integrated USB 2.0 Full-Speed OTG transceiver with dedicated USB PLL eliminates the need for an external USB PHY, reducing BOM cost. The 256 KB Flash holds the Microchip USB stack plus HID report descriptor and application code, while 64 KB SRAM supports HID report FIFOs. The 40 MHz MIPS32 M4K core at 83 DMIPS handles HID polling within the USB 1 ms frame, leaving CPU headroom for LED animation or sensor fusion.
推薦
Capacitive Touch User Interfaces (mTouch)
The PIC32MX270F256BT-I/SO integrates Microchip's mTouch capacitive-touch hardware acquisition module, making it a strong fit for capacitive-touch user interfaces such as appliance control panels, IoT buttons, and slider-based HMI controls. The 10-bit ADC with up to 1.28 Msps sample rate captures capacitive discharge waveforms at high speed, allowing robust touch decoding in noisy environments. 256 KB Flash holds the touch decoding library and a graphical UI; 64 KB SRAM supports button/slider state buffers. The CTMU peripheral provides fine temperature-compensated touch measurement.
推薦
Audio Playback Devices (I2S Codec Interface)
The PIC32MX270F256BT-I/SO supports audio playback devices through its two I2S/SPI modules, which can interface directly to I2S audio DACs and codecs such as the Microchip MCP4921 or external 24-bit audio DACs. DMA with automatic data size detection offloads audio sample movement from the CPU, allowing 48 kHz stereo playback at low MIPS cost. 256 KB Flash holds compressed audio decoders (ADPCM, WAV) while 64 KB SRAM serves as an audio sample buffer. The 40 MHz core can sustain compressed audio decode without audible dropouts.
推薦
Low-Resolution Graphics (PMP-driven TFT)
The PIC32MX270F256BT-I/SO is well suited for low-resolution graphics applications driven through its Parallel Master Port (PMP), which can interface directly to small TFT LCD panels up to 8-bit parallel data width. The peripheral supports Intel 8080 and Motorola 6800 modes and can DMA-frame buffer data, offloading the CPU. 64 KB SRAM is enough to hold small framebuffers for 3.5-inch QVGA panels with reduced color depth. The 40 MHz core handles light graphics drawing operations in firmware.
推薦
Industrial Sensor Hubs with USB Diagnostics
The PIC32MX270F256BT-I/SO fits industrial sensor hub designs that aggregate multiple sensor inputs and expose them over USB to a host PC or industrial controller. Up to 4 hardware DMA channels with automatic data size detection move sensor samples without CPU intervention, supporting high-throughput I2C sensor arrays. USB 2.0 FS OTG enables diagnostics over a standard USB cable, simplifying field service. The industrial -40C to +85C operating range suits factory floor deployment, and the separate USB PLL maintains low-jitter USB signaling under noisy conditions.
推薦
Home Automation and IoT Edge Devices
The PIC32MX270F256BT-I/SO is a strong fit for home automation and IoT edge devices that bridge wired sensors to a USB-attached host or wireless gateway. The 256 KB Flash supports TLS stacks plus application logic, while the 64 KB SRAM holds message buffers and TLS scratch state. PPS lets designers remap UART/I2C pins late in PCB layout, simplifying routing in dense enclosures. The mTouch module adds button/slider UI to wall switches and dimmers, and the on-chip RTCC enables scheduled tasks and calendar-based automation without external RTC chips.
推薦
推薦產品摘要
工程參考資料，適用於 PIC32MX270F256BT-I/SO — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | PIC32MX270F256B-I/SO | PIC32MX170F256BT-I/SO | PIC32MX250F256BT-I/SO | PIC32MX254F128BT-I/SO | PIC32MX150F128BT-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same |
| Program Flash | 256 KB | 256 KB | 256 KB | 256 KB | 128 KB | 128 KB |
| SRAM | 64 KB | 64 KB | 64 KB | 64 KB | 32 KB | 32 KB |
| Core Frequency | 40 MHz | 40 MHz | 40 MHz | 50 MHz | 40 MHz | 40 MHz |
| USB 2.0 OTG | Yes (Full-Speed) | Yes (Full-Speed) | No | No | Yes (Full-Speed) | No |
| PPS (Peripheral Pin Select) | Yes | Yes | Yes | Yes | Yes | No |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| mTouch Cap Touch | Yes | Yes | Yes | Yes | Yes | Yes |
主要差異化特點
- Integrated USB 2.0 Full-Speed OTG with dedicated USB PLL (對比PIC32MX170F256BT-I/SO)
- Full 256 KB Flash and 64 KB SRAM in 28-pin package (對比PIC32MX254F128BT-I/SO)
- Higher-density same-pin-count upgrade over 128 KB Flash siblings (對比PIC32MX150F128BT-I/SO)
設計說明
Provide two decoupling capacitors per the PIC32MX1XX/2XX datasheet guidance: a 0.1 uF ceramic as close as practical to each VDD/VSS pair (pins 6/7 and 16/17 on the 28-SOIC), plus a bulk 10 uF ceramic or tantalum nearby. The VUSB3V3 pin (pin 22) requires a separate regulated 3.3 V rail or a filtered USB-derived rail; never tie VUSB3V3 directly to VDD if the system draws more than the USB suspend budget. Estimated: at 40 MHz active core and full USB, total current draw is approximately 25 mA plus peripheral load, well inside the 500 mA USB budget.
Place the 0.1 uF decoupling capacitor within 1-2 mm of each VDD/VSS pin pair and keep the trace short and wide (>= 0.25 mm). Keep the 28-SOIC land pattern compliant with IPC-7351 SOIC nominal density. For USB signal integrity, route D+/D- (pins 23, 24) as a 90 ohm differential pair with matched length and no splits; place the USB common-mode choke and ESD protection within 5 mm of the connector. Minimize stubs on the crystal traces (pins 25, 26) and place load capacitors within 3 mm of the OSCI/OSCO pins.
Do not drive VUSB3V3 directly from an external 3.3V regulator in designs that may enter USB suspend, as the USB specification requires the device to source less than 2.5 mA on VBUS during suspend and the internal USB transceiver regulator handles this transition. Always configure the unused I/O pins as digital outputs (not analog) to avoid ADC reference contention when scanning analog channels. The PPS peripheral mapping must be configured before peripheral enable; once a peripheral is enabled, remapping its pins can cause transient glitches on the I/O. Estimated: a single bit-banged PPS remap inside an ISR adds 6-8 instruction cycles of latency.
Keep analog input traces (AN0-PG1-AN11 on pins 2-15) away from digital switching traces, particularly the high-speed USB D+/D- pair, to minimize ADC crosstalk. Provide a quiet analog ground island if the application samples low-amplitude analog signals (< 1 mV); this island should connect to the main ground at a single point near the VREF- pin. Keep the trace between VREF+/CVREF+ (pin 10) and the bypass capacitor short (less than 5 mm) for ADC reference stability.
合規資訊
RoHS and REACH compliant per Microchip product page. Industrial temperature grade only - not AEC-Q100 qualified. For AEC-Q100 automotive designs, contact Microchip for PIC32 variants in the automotive grade program.
