How do I identify a TVS diode?

TVS diodes will usually be located near the power connector, but not always. Since TVS diodes in HDD applications are surface mounted devices, they will be identified with an abbreviated marking code rather than a full part number. Some common marking codes for 12V diodes are LE, LEM, LEK, BUX, KVP, 13L.

What is a TVS diode array?

Introduction to TVS Diode Arrays. Littelfuse SPA TVS Diode Arrays are designed to protect analog and digital signal lines, such as USB and HDMI, from various transient threats using the lowest possible clamp voltage. They offer broader application use and improved impulse protection performance over conventional diodes …

How to test a hard drive diode?

A TVS diode can be tested on the diode test range of a digital multimeter. It will have a low resistance in the forward direction, and a high resistance in the reverse direction.

Are diodes used in TVS?

TVS Diodes are used to protect semiconductor components from high-voltage transients. Their p-n junctions have a larger cross-sectional area than those of a normal diode, allowing them to conduct large currents to ground without sustaining damage.

Where should a TVS diode be placed?

Place TVS diode near the edge of the PCB. To enable the excessive surge current to be channeled to chassis ground before damaging the transceiver, the placement of the TVS diode is also important. It is a good practice to place TVS diodes as close to the edge of the board as possible.

Does TVS diode have polarity?

The -C and -CA diodes are bidirectional, there is no polarity marker. On unidirectional diodes the color band usually denotes the cathode.

How do TVS diodes work?

TVS diodes are constructed with large cross sectional area junctions for absorbing high transient currents. As a result, the transient current is diverted away from the protected components and shunted through the TVS diode. The voltage across the pro- tected circuit is limited to the clamping voltage of the TVS diode.

How does a BidiRecTionAl TVS diode work?

BidiRecTionAl TVS deViceS During a transient’s positive cycle, the TVS diode D1 is reversed biased while the other diode D2 is forward biased. D1 acts in avalanche mode (similar to a unidirectional diode) as the transient current (I1) flows to ground.

How do you test a Schottky diode?

Connect the red positive test lead to the anode of the Schottky diode and the black common test lead to the cathode of the diode. Listen for a “beep” or a “buzz” from the multimeter. If the Schottky diode responds as expected, the multimeter will sound a tone.

Where are TVS diodes used?

The TVS diodes fast response time and low clamping voltages make them ideal for use as board level protectors for semiconductors and other sensitive components. Applications include data and signal lines, microprocessors & MOS memory, AC power lines, and telecommunication equipment.

What to look for in a TVS diode array?

Find the TVS Diode Arrays you’re looking for by browsing our products below. Littelfuse TVS Diode Arrays (SPA® silicon protection arrays) are designed to protect electronics from very fast and often damaging voltage transients, such as lightning and electrostatic discharge (ESD).

Where are the diodes located on a HDD?

Which is the best diode array for ESD?

Littelfuse TVS Diode Arrays (SPA ® family of devices) are an ideal choice for suppressing ESD and other electrical transients as their speed and clamping levels are essential to protect today’s integrated circuits.

When did TVS diodes start appearing in HDDs?

TVS diodes started appearing in HDDs in the early to mid 2000s. 7/ What other protection devices does a HDD have? Some drives (eg 2.5″ laptop HDDs) will have a 2A or 4A fuse , others will have a polyswitch , and still others (eg Western Digital) will have a zero-ohm resistor.