Frequently Asked Questions
How is a Bias power supply different from other switching power supplies?
First, there are very few AC/DC switching power supplies available in the 0.5, 1 and 2 watt power ratings. Second, there are no competing designs of these power ratings and physical size which are isolated. Third, there are no competing designs of these power ratings and physical size which do not need external filtering to meet EMI specifications.
Why do you say that a Bias supply does not require any external filtering?
Bias products incorporate a proprietary technology which greatly reduces the generation of EMI. The levels achieved are within the limits specified in FCC Part 15 and EN 55022, Class B.
I have always used an external power supply to avoid UL approvals of our products. How would an internal Bias supply help in this process?
All Bias modules are UL Component Recognized to 60950 and a CB report is available. Contact us for more details.
We’ve always designed our own low-power supplies on-board. Why should I consider using a Bias supply instead?
A variety of considerations are appropriate.
- The design is complete, you need not invest any time in design so you can spend more time designing product features valuable to your customers.
- If your designs are space constrained, no other technically comparable designs are as small.
- Bias modules have an application flexibility difficult to achieve with other designs. Contact Bias for details.
- Instead of needing to source a variety of components and maintaining inventory on each, you have just one module to deal with.
- Bias products are UL Component Recognized (see above) simplifying your process.
How is it that Bias can help me meet Energy Star requirements?
Many Energy Star requirements, and specifically those for appliances, specify standby power of 1 watt or less. Generally, this has required a significant re-design of an existing power supply. The use of the Bias module can often reduce the design time to accomplish these requirements.
I have a low-power application requiring peak power that is more than two watts. Will a Bias supply work?
Yes! There are two approaches.
- Bias supplies can easily handle highly capacitive loads. Adding capacitance on the output may be capable of providing the peak power required.
- Bias supplies can be connected in parallel without additional circuitry. Simple parallel or N+X designs can be accomplished.
For low-power applications, I’ve always used simple linear power supplies. Why should I consider switchers like the Bias supplies?
Efficiency, Efficiency, Efficiency!
Can I run two Bias power supplies in parallel?
Yes, and without any load-sharing circuitry or droop resistors.
I’m a bit confused about exactly what is coming out of the multiple outputs on some of your supplies. Can you explain?
All current Bias supplies develop a single DC output. This output, while well regulated at either 8 VDC or 14 VDC develops ripple at either 100Hz or 120Hz as load is increased. In many applications, this ripple is acceptable. For some applications, some smoothing is required. External capacitors can provide a reduction in this ripple, as can the use of a linear regulator. For supplies with part numbers ending in -50, Bias provides an internal linear regulator. The input to this regulator is the 8 VDC supply.
The instrument I’m designing will be used worldwide with different line voltages and frequencies. What should I know about how a Bias power supply will work in this situation?
Bias supplies are designed to operate at standard 50Hz and 60Hz line voltages from 85 VAC to 265 VAC. Specific performance specifications are available on the appropriate data sheet.
My circuit requirements are somewhat different than your standard models match up to. Can you customize your product to meet my requirements? If so, what’s the minimum quantity?
Bias will consider special designs where annual quantity commitments exceed 100,000 units. Other requirements may be met without actual product changes. Tell us about your needs.
How do I get samples?
Are Bias power products available through distributors?
A growing list of North American and International distributors carry Bias products. Check the Bias web site under “Where To Buy” for details.
In the past, we used an earlier generation of Bias power supplies with different pin-out configurations. Is there any way that I can match a new supply to our old boards?
Available space and some technical specification differences will determine this. The best approach is to contact Bias.
I don’t see any specification for what switching frequencies you use.
Bias products use a switching frequency slightly less than 100kHz.
My department has been downsized and we really don’t have a power guy here anymore. Can you assist with applications engineering support?
Please call us with details about your specific power, space and environmental requirements.
If you don't see the answer to your question, please contact us!
Thank you for your interst in Bias products!
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