{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"ATTINY45-20SU","brand":"Microchip Technology","brandSlug":"microchip","productSlug":"ATTINY45-20SU","canonicalUrl":"https://icboms.com/microchip/ATTINY45-20SU","factsUrl":"https://icboms.com/api/mcp/products/ATTINY45-20SU","rawCanonicalId":null},"summary":{"shortDescription":"Microchip AVR® ATtiny, Functional Safety (FuSa) series, ATTINY45-20SU, 8-Bit MCU, 20MHz, 4KB FLASH, 256 x 8 RAM, 256 x 8 EEPROM, 8-SOIC, -40°C~85°C.","salesMarkdown":"## 20 MHz 8-bit AVR in an 8-SOIC — small-package control for industrial and battery applications The Microchip ATTINY45-20SU is an 8-bit AVR microcontroller from the ATtiny family, qualified under the Functional Safety (FuSa) initiative. It runs at 20 MHz from an internal oscillator, with 4 KB of Flash program memory, 256 bytes of SRAM, and 256 bytes of EEPROM — a memory footprint sized for single-purpose control loops, state machines, and sensor conditioning. The 8-SOIC package keeps board area small, and the six general-purpose I/O lines (shared with the 4-channel 10-bit ADC and the Universal Serial Interface) handle basic switch sensing, PWM generation, and serial communication without external glue logic. Brown-out detect and power-on reset are integrated, so a simple decoupling cap on the supply pin is enough for reliable startup. At 20 MHz the AVR core executes most instructions in a single clock cycle, giving roughly 20 MIPS throughput. That is enough for 10 kHz to 50 kHz control loops with headroom for ADC conversions and USI-based serial polling. ## Memory map and field-update reality The 4 KB Flash is self-programmable via the bootloader section, so firmware updates over the USI or a custom protocol are possible — but 4 KB fills fast with a bootloader plus application code. The 256 bytes of EEPROM are useful for calibration constants and fault logs that survive power cycles; endurance is rated for 100k writes per byte in the AVR architecture. With only 256 bytes of SRAM, stack depth and interrupt nesting need careful budgeting — a deep function-call tree or large local arrays will overflow silently.","metaTitle":"ATTINY45-20SU AVR 8-bit MCU, 20 MHz, 4 KB Flash, 8-SOIC","metaDescription":"Microchip ATTINY45-20SU 8-bit AVR MCU with 20 MHz core, 4 KB Flash, 256 B SRAM, 256 B EEPROM, 10-bit ADC, 6 I/O, -40°C to 85°C. Active lifecycle.","metaKeywords":null},"attributes":{"series":"AVR® ATtiny, Functional Safety (FuSa)","packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Microcontrollers & Processors (MCU / MPU / DSP)"],"specifications":{"Mfr":"Microchip Technology","Speed":"20MHz","Series":"AVR® ATtiny, Functional Safety (FuSa)","Package":"Tube","RAM Size":"256 x 8","Core Size":"8-Bit","EEPROM Size":"256 x 8","Peripherals":"Brown-out Detect/Reset, POR, PWM, WDT","Connectivity":"USI","Mounting Type":"Surface Mount","Number of I/O":"6","Core Processor":"AVR","Package / Case":"8-SOIC (0.209\\\", 5.30mm Width)","Product Status":"Active","Data Converters":"A/D 4x10b","Oscillator Type":"Internal","lifecycle_stage":"eol_hot","Base Product Number":"ATTINY45","Program Memory Size":"4KB (2K x 16)","Program Memory Type":"FLASH","Operating Temperature":"-40°C~85°C(TA)","Supplier Device Package":"8-SOIC","Voltage - Supply (Vcc/Vdd)":"2.7V ~ 5.5V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.6600","priceTiers":[{"qty":1,"price":"$1.47000","currency":"USD"},{"qty":25,"price":"$1.35720","currency":"USD"},{"qty":100,"price":"$1.21900","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/e886a731351a5f5ffba7407b7da95a58.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/ATTINY45-20SU/alternatives.json"},"ai":{"faq":[{"question":"What is the replacement or equivalent for ATTINY45-20SU?","answer":"Microchip does not list a direct pin-compatible replacement for the ATTINY45-20SU. The newer ATtiny3224 series (ATTINY3224-XUR) offers a 20 MHz core with 12 I/O and more memory, but in a different package — verify footprint compatibility before substituting."},{"question":"Can ATTINY45-20SU be programmed with Arduino?","answer":"Yes — the ATtiny45 is supported by the Arduino IDE via the ATTinyCore or MicroCore board packages. Programming uses an ISP (SPI) interface through a standard Arduino board or a dedicated programmer like the USBasp."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/microchip/ATTINY45-20SU","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/microchip/ATTINY45-20SU when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-20T14:34:45.345Z","lastPublished":"2026-07-20T14:34:45.345Z","indexable":true}}