Single SPDT Analog Switch Saves Space in Portable Consumer and Medical Devices

Date
10/16/2017

 PDF
Device Offers -3 dB Bandwidth of 700 MHz and Power Down Protection in New Ultra Compact μDFN6 Package

MALVERN, Pa. — Vishay Intertechnology, Inc. introduced a new single SPDT analog switch that is the company's first device in the new ultra compact μDFN6 package. Ideal for analog and digital signal switching in portable consumer and medical devices, the Vishay Siliconix DG3257 achieves low resistance of 5 Ω at 4.2 V while delivering improved high bandwidth, reduced parasitic capacitance, and a power-down protection feature.

Measuring just 1 mm by 1 mm by 0.35 mm, the device released today is 29 % smaller and 36 % thinner than switches in the mQFN6 package. This allows the DG3257 to save valuable PCB space in smartphones, tablets, and e-readers; wearable devices such as smart watches and fitness trackers; portable medical instrumentation; cameras and audio devices; IoT applications; computers and peripherals; and data storage devices.

While previous generation devices offer -3 dB bandwidth of 300 MHz, the DG3257 achieves extremely high bandwidth of over 700 MHz. This 5 Ω SPDT device features break-before-make switching with a 17 ns turn-on time and an ultra low 100 ps propagation delay. The switch features ‑32 dB crosstalk at 240 MHz — a 10 dB improvement over competing solutions — and -33 dB off-isolation. The device is fabricated with a high density sub-micron CMOS process to deliver 50 % lower parasitic capacitance CD(ON) of 9 pF and CS(OFF) of 3 pF.

The DG3257 handles bidirectional signal flow with minimal distortion and can be powered directly from a one-cell Li-ion battery. Designed to operate from 1.65 V to 5.5 V, the DG3257 guarantees less than 1 μA of leakage current in the power-down condition. This feature prevents excessive current from feeding into the switch when the power supply is removed. The device has a 1.4 V logic threshold to ensure low voltage TTL/CMOS compatibility. When interfacing with low voltage MCUs, the switch offers guaranteed maximum power consumption of 1.5 μA, which is 90 % lower than competing devices.

The RoHS-compliant device offers ESD tolerance > 6 kV (human body model) and latch up current of 300 mA per JESD78.

www.vishay.com

RELATED

 


-->