The HD resistor series from Alpha Electronics offers their ultra-precision resistor capabilities in a hermetically sealed package. With a resistance range from 1Ω up to 120kΩ all in a small through-hole package with a pin pitch of 5.08 ±0.25mm. By utilising Alpha’s Bulk Metal® foil resistor technology, they are able to produce resistors with low temperature coefficients and excellent long-term stability.
Ultra-precision hermetically sealed resistor
Available in any resistance between 1Ω and 120kΩ
Through-hole package with a pin pitch of 5.08 ±0.25mm
Tight tolerance options as low as ±0.005% available for resistances between 30Ω and 120kΩ
Tight TCR options available of ±1 ppm/°C (from 0°C up to +65°C, between 30Ω and 120kΩ) or ±2.5 ppm/°C (from -55°C up to +125°C, between 30Ω up to 120kΩ)
Maximum working voltage of 300V
Power rating of 0.3W (at +125°C)
Maximum rated operating temperature +125°C
Temperature range from -65°C up to +150°C
The Alpha Electronics HD hermetically sealed ultra-precision resistor series have been designed with longer leads to ensure the correct clearance from the PCB is achieved when soldering. It is advised that the resistors are kept over 10mm away from the board surface by using an insulating tube.
The below table gives a summary of the specifications available for each resistor model including the Alpha HD series:
* Symbols parenthesized are for part number composition
✝ Resistance figures are the values obtained by measuring the leads at point 12.7±3.2mm away from the base for type HC and HD, but, in case of resistance below 10Ω, the value at 1.6 ±0.6mm away from the base for all types
** Temperature characteristic Z is applicable for temperature range between 0°C and +60°C
Alpha Manufacturing and Product Information
Alpha Electronics manufacturing process, adjustment of resistance value construction, and temperature characteristics of resistance information
We are pleased to provide you with a range of videos, please see below for the latest content available:
VIDEOS
Resistor Stability Put to the Test (Demo Video)
In this video, our host Richard Zuratt puts the stability of the three major resistor technologies — foil, thin, and thick film — to the test. Each resistor type is subjected to an overload pulse and its change in resistance value is recorded. Due to the homogeneous nature of the VPG Bulk Metal® Foil resistor, it is the only of the three to experience no change from the high power pulse. This demonstrated performance makes foil resistors the technology of choice for critical applications where long-term stability and survivability are paramount.
Advantages of Using Bulk Metal® Foil Resistors in High-Humidity Environments
All resistors that are based on nichrome, which is a category that includes both thin film devices and Bulk Metal Foil resistors, are susceptible to electro-chemical corrosion or etching when placed in a high humidity environment and powered with a very low wattage. But since the nichrome element of a Bulk Metal Foil resistor is hundreds of times thicker than the element in a thin film device with the same value, it will last much longer under these conditions. This video shows the actual etching process and survival times for thin film and foil nichrome resistive elements as they are tested in 100% humidity conditions.
Comparison Testing of Chip Resistor Technologies Under High Vibration
Surface-mount resistors suffer physical stresses when exposed to high vibration or thermally unstable environments. Failure modes commonly occur in welds, solder joints, connectors, and terminations, ultimately resulting in circuit failure. In this demonstration, vibration-table-mounted boards are subjected to ±2° deflection 25 times per second and monitored for any ΔR > 0.1%. All the chip resistors failed in 2 to 12 minutes (8K to 16K cycles). But the Alpha MPP molded Bulk Metal® Z-Foil resistor with flexible terminations experienced over a million cycles with no change in resistance.
VIDEOS
Resistor Stability Put to the Test (Demo Video
In this video, our host Richard Zuratt puts the stability of the three major resistor technologies — foil, thin, and thick film — to the test. Each resistor type is subjected to an overload pulse and its change in resistance value is recorded. Due to the homogeneous nature of the VPG Bulk Metal® Foil resistor, it is the only of the three to experience no change from the high power pulse. This demonstrated performance makes foil resistors the technology of choice for critical applications where long-term stability and survivability are paramount.
Advantages of Using Bulk Metal® Foil Resistors in High-Humidity Environments
All resistors that are based on nichrome, which is a category that includes both thin film devices and Bulk Metal Foil resistors, are susceptible to electro-chemical corrosion or etching when placed in a high humidity environment and powered with a very low wattage. But since the nichrome element of a Bulk Metal Foil resistor is hundreds of times thicker than the element in a thin film device with the same value, it will last much longer under these conditions. This video shows the actual etching process and survival times for thin film and foil nichrome resistive elements as they are tested in 100% humidity conditions.
Surface-mount resistors suffer physical stresses when exposed to high vibration or thermally unstable environments. Failure modes commonly occur in welds, solder joints, connectors, and terminations, ultimately resulting in circuit failure. In this demonstration, vibration-table-mounted boards are subjected to ±2° deflection 25 times per second and monitored for any ΔR > 0.1%. All the chip resistors failed in 2 to 12 minutes (8K to 16K cycles). But the Alpha MPP molded Bulk Metal® Z-Foil resistor with flexible terminations experienced over a million cycles with no change in resistance.
Alpha HC, HD and HG Series Ordering Info
Below will contain available parts / ordering information for the product