Circuit & System Protection


Clamping diodes

28 April 2010 Circuit & System Protection

The PolyZen family of clamping diodes from Tyco Electronics offers designers the simplicity of a traditional clamping diode while obviating the need for significant heatsinking.

This single device solution helps protect against damage resulting from the use of improper power supplies and also provides transient suppression, reverse bias protection and protection from damage caused by over-current events.

The device’s micro-assembly incorporates a stable Zener diode for crisp voltage clamping and a resistively non-linear polymeric positive temperature coefficient (PPTC) layer. The PPTC layer responds to either diode heating or over-current events by transitioning from a low- to a high-resistance state. In the event of a sustained high-power over-voltage condition, the tripped PPTC element limits current and generates a voltage drop to help protect both the Zener and the follow-on electronics – effectively increasing the diode’s power handling capability.

The PolyZen is particularly effective at clamping and smoothing inductive voltage spikes. In response to an inductive spike, the Zener diode element shunts current to ground until the voltage is reduced to the normal operating range. In the case of power supply of the incorrect voltage, the device clamps the voltage, shunts excess power to ground, and eventually locks out the incorrect supply. The relatively flat voltage versus current response of the device helps clamp the output voltage, even when input voltage and source currents vary. The PolyZen offers power handling on the order of 30 W and available hold currents up to 2,3 A.

For more information contact Jeva Narian, Arrow Altech Distribution, +27 (0)11 923 9600, [email protected], www.arrow.altech.co.za



Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Altron celebrates 60th birthday with a call to rebuild Johannesburg
Altron Arrow News
Altron is celebrating its 60th birthday by honouring Johannesburg’s heritage and encouraging business, government and civil society to come together and respond to our President’s call to rebuild Johannesburg.

Read more...
Reference board for cardio monitoring
Altron Arrow Telecoms, Datacoms, Wireless, IoT
The STDES-ESP01 reference board from STMicroelectronics demonstrates the capability of the ST1VAFE6AX and ST1VAFE3BX biosensors to detect ECG and SCG signals.

Read more...
ST MCUs extend ultra-low power innovation
Altron Arrow DSP, Micros & Memory
STMicroelectronics has introduced new STM32U3 microcontrollers with cutting-edge power-saving innovations that ease deployment of smart connected tech, especially in remote locations.

Read more...
Multicell battery monitoring
Altron Arrow Power Electronics / Power Management
The LTC6811 from Analog Devices is a multicell battery stack monitor that measures up to 12 series connected battery cells with a total measurement error of less than 1,2 mV.

Read more...
Clearing the Static: Conductive foot, heel and shoe grounders
Actum Electronics Circuit & System Protection
Conductive foot, heel and shoe grounders are used in electrostatic discharge protected areas to provide a path to ground for static electricity.

Read more...
Innovative satellite navigation receiver
Altron Arrow Telecoms, Datacoms, Wireless, IoT
STMicroelectronics has released an innovative satellite navigation receiver to democratise precise positioning for automotive and industrial applications.

Read more...
LED driver for industrial power supply indication
Altron Arrow Editor's Choice Circuit & System Protection
A simple and small solution for driving an LED to provide visual feedback in the presence/absence of a system’s power using a chip not originally designed for this purpose.

Read more...
High-voltage step-down DC-DC converter
Altron Arrow Power Electronics / Power Management
The MAX17793 is a high-efficiency, high-voltage, synchronous step-down DC-DC converter with integrated MOSFETs operating over an input voltage range of 3 to 80 V.

Read more...
Clearing the Static: Cleaning in an ESD-protected area
Actum Electronics Circuit & System Protection
Cleaning in a protected electrostatic discharge area is a critical task to maintain the integrity of sensitive electronic components and prevent damage caused by static electricity.

Read more...
High-speed SAR ADC simplifies design
Altron Arrow Analogue, Mixed Signal, LSI
The ADI AD4080 simplifies data converter integration by integrating a low drift reference buffer, low dropout regulators and a 16K result data FIFO buffer.

Read more...