Power Struggles and the Benefits of 6-Pin SMPS Controllers

Do more with less. It’s a common directive, even when it comes to power  supplies. Whether the assignment is to improve power density and keep costs down or to push even farther to make power supplies smaller, lighter and in line with stringent energy efficiency standards, it usually comes down to a trade-offs.

For example, one approach that IC designers have taken to meet power challenges is to move away from AC-DC controllers in 8-pin packages to smaller 6-pin options. Despite the power advantages, it’s widely believed that moving from 8-pin to 6-pin controllers results in the loss of the protection functionality available on 8-pin solutions.

This and other vexing demands of power are no longer an issue with a move to NXP’s next-generation TEA1833. This 6-pin controller, part of the acclaimed GreenChip family of power  ICs, is a popular solution in medium power systems. The TEA1833 fixed frequency flyback controller enables compact and cost-efficient power supplies for designs up to 65 W. It also overcomes the potential function drawbacks of 6-pin designs and the challenges of the most demanding energy efficiency standards.

Knocking down the pins without losing protection
The TEA1833 comes in an industry-standard 6-pin TSOP6 (or SOT223-6) package. To ensure no functionality normally found on an 8-pin package is lost, the device employs pin functionality multiplexing.

• It offers integrated and accurate Over Voltage Protection (OVP) via the ISENSE pin and with Over Power Protection (OPP) the power supply can handle an overpower situation up to 200 % for a limited amount of time.
• Adjustable high/low line compensation is delivered by measuring the Bulk capacitor voltage via pin PROTECT while the offset is generated via pin ISENSE.
• Brown-in and brown-out function is offered via pin PROTECT while external Over Temperature Protection (OTP) and/or OVP can be easily implemented using a minimal number of external components.

Improving power consumption at no-load
As part of the ongoing trend to improve energy efficiency and no-load standby performance, external power supply designs must comply with the latest versions of the EU Code of Conduct (CoC). The imminent introduction of a CoC Tier 2 requirement means all new designs must achieve no-load standby consumption of < 75 mW (Pout > 49W). The TEA1833 meets this with ease, delivering one of the industry’s lowest ratings of around 65 mW – a significant achievement for such a small controller IC. Of course, all performance characteristics are top class.

Less fuss and less plastic
Thanks to multiplexing over 6 pins, the TEA1833 meets the needs of designers who want full functionality along with the opportunity to save board space. Designers can also enjoy ease of design-in – for example the device’s wide supply voltage range, up to approximately 40 V, affords excellent flexibility. Furthermore the TEA1833 meets the demands of the latest energy standards.