CS1820 - EMI Filter for T-Flash/MicroSDXC Interfaces


  • ±12kV ESD protection
  • Bidirectional EMI/RFI filter arrays and line termination with integrated ESD protection
  • (IEC 61000-4-2, contact discharge)
  • TVS working voltage: 5V
  • Termination resistors: 40Ω
  • Pull Up Resistors: 25kΩ
  • Typical capacitance per line: 18pF (VR= 2.5V)
  • Protection and termination for six lines + Vcc
  • uDFN package with0.40mmlead pitch:
  • 16-lead,3.30mm×1.35mm×0.50mmfootprint
  • RoHS-compliant, Lead-free packaging
  • Device meets MSL 1 requirements


The CS1820 is a combination EMI filter and line termination device with integrated electrostatic discharge (ESD) protection for use on Multimedia Card interfaces. The CS1820 has been optimized for protection of T-Flash/MicroSD interfaces in mobile phones and other portable devices.

The CS1820 consists of six circuits that include series impedance matching resistors and pull-up resistors as required by the SD specification. TVS diodes are included on each line for ESD protection. An additional TVS diode connection is included for protection of the voltage (Vcc) bus. Termination resistor value of 40Ω is provided on the DATA0, DATA1, DATA2, DATA3, CMD, and CLK lines. Pull up resistors of 25kΩ are included on DAT0, DAT1, DAT2, DATA3, and CMD lines. These may be configured for devices operating in SD or SPI mode. The integrated ESD protection diodes provide robust ESD protection of ±12kV (contact) under IEC 61000-4-2.

The CS1820 comes in space saving, low profile,0.40mmpitch uDFN package and is available in lead-free packaging.


· T-Flash / MicroSD Interfaces

· MMC Interfaces

· CDMA, GSM,3GCell Phones