{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"CY8C3665LTI-044","brand":"Infineon Technologies","brandSlug":"infineon","productSlug":"CY8C3665LTI-044","canonicalUrl":"https://icboms.com/infineon/CY8C3665LTI-044","factsUrl":"https://icboms.com/api/mcp/products/CY8C3665LTI-044","rawCanonicalId":null},"summary":{"shortDescription":"Cypress PSOC® 3 CY8C36xx series CY8C3665LTI-044, 8-bit 8051 MCU, 67 MHz, 32 KB Flash, 4K x 8 RAM, 1K x 8 EEPROM, 38 I/O, CapSense, USB, 12-bit ADC, -40°C to 85°C, 68-VFQFN Exposed Pad, Tray.","salesMarkdown":"## What this PSoC 3 brings to the board It is a mixed-signal controller — the headline feature is the integrated CapSense block for touch-sensing, plus a 12-bit ADC array (16 channels) and four 8-bit DACs, all on a single die. The 1.71V to 5.5V supply range means you can power it straight from a Li-ion cell or a 5V industrial rail without an extra regulator, which simplifies the power tree on a space-constrained board. ## 67 MHz 8051 — what that means for throughput At 67 MHz, this 8051 core is roughly on par with a mid-range ARM Cortex-M0 in integer math, but the real advantage is the programmable analog and digital blocks. The 12-bit ADC can sample at rates suitable for audio or sensor acquisition while the CPU handles USB traffic and CapSense scanning. If you are coming from a slower 8-bit part, budget for the flash wait state — the PSoC 3's flash accelerator needs a single wait state above about 24 MHz, so the 67 MHz figure is achievable with the right clock configuration. ## CapSense, USB, and the peripheral set This part is built for human-interface and control applications. The CapSense block handles capacitive touch buttons, sliders, and proximity sensing without an external controller — a common choice for appliance front panels, medical keypads, and industrial HMIs. USB connectivity (full-speed, likely) lets it talk directly to a host for configuration or data logging. The DMA engine offloads data movement between the ADC, USB, and memory, which keeps the CPU free for higher-level tasks. ## Package and thermal reality The 68-VFQFN with exposed pad (8x8 mm) is a compact, low-inductance package, but it is not a field-swap-friendly part — you will need a hot-air station or a reflow oven to replace it. Without that, the junction temperature climbs quickly above 400 mA continuous I/O load. MSL 3 out of the bag: bake before reflow if the moisture-barrier bag has been open longer than the floor-life window. It is at home in factory automation panels, outdoor telecom cabinets, automotive cabin modules (non-safety), and any environment where the board sees seasonal temperature swings but not engine-bay extremes. The internal oscillator (no external crystal needed for basic operation) saves a component, though for accurate USB timing you will still want an external resonator or crystal. ## Lifecycle and sourcing posture Cypress (now part of Infineon) lists the CY8C3665LTI-044 as Active in the product lifecycle.","metaTitle":"Cypress CY8C3665LTI-044 PSoC 3 MCU, 8-bit 8051, 67 MHz","metaDescription":"Cypress CY8C3665LTI-044 PSoC 3 MCU: 8-bit 8051 core at 67 MHz, 32 KB Flash, 4K x 8 RAM, CapSense, USB, 12-bit ADC, -40°C to 85°C, 68-QFN.","metaKeywords":null},"attributes":{"series":"PSOC® 3 CY8C36xx","packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Logic ICs"],"specifications":{"Speed":"67MHz","Series":"PSOC® 3 CY8C36xx","Package":"Tray","RAM Size":"4K x 8","Core Size":"8-Bit","EEPROM Size":"1K x 8","Peripherals":"CapSense, DMA, POR, PWM, WDT","Connectivity":"EBI/EMI, I²C, LINbus, SPI, UART/USART, USB","Mounting Type":"Surface Mount","Number of I/O":"38","Core Processor":"8051","Package / Case":"68-VFQFN Exposed Pad","Data Converters":"A/D 16x12b; D/A 4x8b","Oscillator Type":"Internal","lifecycle_stage":"eol_hot","Program Memory Size":"32KB (32K x 8)","Program Memory Type":"FLASH","Operating Temperature":"-40°C ~ 85°C (TA)","Supplier Device Package":"68-QFN (8x8)","Voltage - Supply (Vcc/Vdd)":"1.71V ~ 5.5V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$14.19","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$14.19000","currency":"USD"},{"qty":10,"price":"$13.04100","currency":"USD"},{"qty":25,"price":"$12.50040","currency":"USD"},{"qty":80,"price":"$11.01375","currency":"USD"},{"qty":260,"price":"$10.47319","currency":"USD"},{"qty":520,"price":"$9.79750","currency":"USD"},{"qty":1040,"price":"$8.98667","currency":"USD"}]},"links":{"datasheetUrl":"https://www.infineon.com/cms/en/product/microcontroller/legacy-microcontroller/legacy-8-bit-16-bit-microcontroller/psoc-3/cy8c36xxx/cy8c3666axi-052t/#!?fileId=8ac78c8c7d0d8da4017d0ec73d263e88","sourceUrl":null},"ai":{"faq":[{"question":"What programmer or debugger supports CY8C3665LTI-044?","answer":"The PSoC 3 family uses Cypress's MiniProg3 or MiniProg4 programmer/debugger via the SWD interface. The PSoC Creator IDE handles the toolchain. No special adapter is needed — the 68-QFN package exposes the SWD pins on the outer row."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/infineon/CY8C3665LTI-044","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/infineon/CY8C3665LTI-044 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-17T19:50:00.618Z","lastPublished":"2026-07-17T19:50:00.618Z","indexable":true}}