{"license":"Free for any use with attribution link to rfid-datasheet.com","citation":"RFID-Datasheet.com Chip Database — Roxtron","source":"https://rfid-datasheet.com/chip/em4205-em4305","methodology":"https://rfid-datasheet.com/methodology","data_notes":"Includes automated enrichment. Null means unknown; last_checked is link availability, not technical review. Manufacturer documents govern specifications.","generated_at":"2026-11-02T00:54:20.573Z","chip":{"id":"6fbf8d09-eab5-4645-a4ff-d46e5193497f","slug":"em4205-em4305","name":"EM4205 / EM4305","manufacturer":"EM Microelectronic","frequency_category":"LF 125 kHz","short_description":"512-bit R/W multi-purpose transponder","manufacturer_url":"https://www.emmicroelectronic.com/sites/default/files/products/datasheets/4205-4305-DS-01.pdf","frequency":"125 kHz (100 to 150 kHz range)","protocol":"ISO 11784 / 11785 Standard Compliant, compatible with EM4469/EM4569 communication protocol","memory":"512 bit EEPROM organized in 16 words of 32 bit (288 bits user free in words 5-13), 32 bit unique identifier (UID), 32 bit password","interface":"RF (contactless)","temp_range":"-40°C to +85°C","form_factor":"EMDFN02 (2.2 x 1.78 x 0.76 mm), EMDFN403 (1.1 x 1.4 x 0.46 mm), die/wafer form available","security":"32 bit password read and write protection, lock feature converts EEPROM words into read-only","use_cases":["animal-identification","access-control","asset-tracking"],"engineering_brief":"The EM4205/4305 is a 125 kHz LF read/write RFID transponder with 512 bits of EEPROM organized as 16×32-bit words, compliant with ISO 11784/11785 for animal identification. It features a factory-programmed 32-bit UID, 32-bit password protection, configurable data rates (RF/8 to RF/64), and supports both Manchester and Bi-phase encoding. The chip includes on-chip rectifier, voltage limiter, integrated resonant capacitor (210pF, 250pF, or 330pF versions), and operates without external supply buffer capacitor across industrial temperature range.","enriched":true,"url_status":"ok","link_status":"invalid","last_checked":"2026-11-01T03:31:28.371+00:00","last_status_code":200,"last_content_type":"text/html; charset=UTF-8","created_at":"2026-06-14T16:30:56.111445+00:00","manufacturer_id":"64ce2a57-06a6-425b-84dc-f4bd9eec0c36","chip_type":"tag_ic","dual_interface":false,"is_family_hub":false,"meta_description":"EM4205/4305 125 kHz R/W RFID tag IC with 512-bit EEPROM, 32-bit password protection, ISO 11784/11785 compliant for animal ID and access control.","faq":[{"a":"The EM4205 has 512 bits of EEPROM organized as 16 words of 32 bits each, with 288 bits available as user-free memory in words 5-13. It also includes a factory-programmed 32-bit unique identifier (UID).","q":"What is the memory capacity of the EM4205 chip?"},{"a":"Yes, the EM4205/4305 is fully compliant with ISO 11784/11785 standards for animal identification. It is also compatible with the EM4469/EM4569 communication protocol.","q":"Is the EM4205 compatible with ISO 11784/11785 animal identification standards?"},{"a":"The EM4305 provides 32-bit password protection for both read and write operations. It also includes a lock feature that can convert EEPROM words into read-only mode for permanent data protection.","q":"What security features does the EM4305 offer?"},{"a":"The EM4205 operates at 125 kHz with a working range of 100 to 150 kHz, making it a low-frequency (LF) RFID transponder chip.","q":"What is the operating frequency range of the EM4205?"},{"a":"The EM4205 includes an integrated resonant capacitor available in 210pF, 250pF, or 330pF versions and operates without requiring an external supply buffer capacitor.","q":"Does the EM4205 require external capacitors?"},{"a":"The EM4305 supports both Manchester and Bi-phase encoding formats with configurable data rates ranging from RF/8 to RF/64.","q":"What data encoding formats does the EM4305 support?"}],"standards":["iso-11784-11785"],"alternatives":["3d5557e0-57db-43d5-81b6-19e1b2a93cab","a9e71908-817a-43b2-a0ce-0d180be72f27","de787ff0-5b24-47b3-b28b-3d404e2eda36"],"no_direct_competitor":false,"long_form_html":null,"og_image_url":null,"canonical_url":"https://rfid-datasheet.com/chip/em4205-em4305"}}