Suppression devices have SD memory cards covered

Edited by the Electronicstalk editorial team Jan 25, 2005

The latest addition to the Semtech EMIClamp family of transient voltage suppression devices is specifically designed to protect interfaces for Secure Digital (SD) memory card designs.

The latest addition to the Semtech EMIClamp family of transient voltage suppression devices is specifically designed to protect interfaces for Secure Digital (SD) memory card designs.

The EClamp2357N features six lines of combined protection from electromagnetic interference (EMI), radio frequency interference (RFI) and electrostatic discharge (ESD).

It also includes an additional four lines of dedicated ESD protection for power and high-speed I/O lines.

"Expanding our successful EClamp family to support SD Memory Card interfaces was an easy choice, because the growth of this format has been so dramatic", said Tom Dugan, Semtech's Director of Protection Products.

"The EClamp2357N offers designers a true, cost-effective alternative complete with small size, excellent protection, and industry preferred packaging".

The SD Memory Card has quickly become the standard for high-capacity consumer device storage thanks to its high-speed data transfer capabilities.

While designed for SD Memory Card interfaces, the EClamp2357N can also be used in touch screen display, mobile phone handset, colour LCD and multimedia colour interface applications.

The EClamp2357N sits on a board between the SD memory connector and the baseband controller and protects the controller from transient electrical events.

The EClamp replaces up to 28 discrete devices on a board with just one 3 x 3mm, 16-pin quad flat no-lead (QFN) that can be integrated into most assembly processes.

In addition, the device's easy layout increases filter and ESD performance through reduced trace inductance.

Each of the six circuits on the EClamp2357N comprises a pi filter circuit that includes TVS diodes for ESD protection, and a resistor capacitor network for EMI/RFI filtering.

The device also features four lines of TVS diodes for dedicated ESD protection of power lines or high-speed I/O lines.

A series resistor value of 100ohm and a component capacitance value of 10pF are used to achieve 20dB minimum attenuation from 1.0 to 3GHz.

All the TVS diodes provide effective suppression of ESD voltages in excess of 15kV (air discharge) and 8kV (contact discharge) per the IEC61000-4-2, level 4 specification.

The EClamp2357N is available immediately in production quantities and is priced at $0.55 each in 1000 piece lots.

The device comes in a lead-free, 16-pin QFN package.

Semtech offers comprehensive design assistance, including field- and factory-based support.