LF 125 kHzEM Microelectronic

EM4205 / EM4305

Name: EM Microelectronic EM4205 / EM4305
Brand: EM Microelectronic

The EM Microelectronic EM4205 / EM4305 is an LF 125 kHz RFID tag IC, with 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, operating at 125 kHz (100 to 150 kHz range), under ISO 11784 / 11785 Standard Compliant compatible with EM4469/EM4569 communication protocol.

512-bit R/W multi-purpose transponder

Official Datasheet ↗

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

Full Specifications

Manufacturer	EM Microelectronic
Frequency Category	LF 125 kHz
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)
Temperature 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

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.

Typical Applications

Standards & Compliance

ISO 11784 / 11785 (Animal ID)

Frequently Asked Questions

What is the memory capacity of the EM4205 chip?

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).

Is the EM4205 compatible with ISO 11784/11785 animal identification standards?

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.

What security features does the EM4305 offer?

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.

What is the operating frequency range of the EM4205?

The EM4205 operates at 125 kHz with a working range of 100 to 150 kHz, making it a low-frequency (LF) RFID transponder chip.

Does the EM4205 require external capacitors?

The EM4205 includes an integrated resonant capacitor available in 210pF, 250pF, or 330pF versions and operates without requiring an external supply buffer capacitor.

What data encoding formats does the EM4305 support?

The EM4305 supports both Manchester and Bi-phase encoding formats with configurable data rates ranging from RF/8 to RF/64.

Explore

Manufacturer

All EM Microelectronic chips →

Standards

ISO 11784 / 11785 (Animal ID)

Applications

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