green-techZONE Products for the week of May 31, 2004
Power Miser: Philips's GreenChip Power Supply
Controller Delivers High Efficiency, Low Standby Power, And Lower Cost
Royal Philips Electronics has expanded its industry-leading family
of energy efficient GreenChip power ICs with the introduction of a highly
integrated off-line flyback control IC. Featuring multiple modes of operation,
the chip enables manufacturers of applications such as printers and other
adapters, LCD monitors, set-top boxes and DVD recordable drives to reduce
power and increase efficiency.
With the proliferation of power-intensive devices in the home, there is a need for more energy efficient solutions to lower power costs for the consumer and help sustain a greener environment. Philips' GreenChip family meets this need with a range of solutions to enable efficient power usage in today's consumer electronic devices, both in standby mode and while in use.
"The customer demand for Philips' GreenChip ICs is huge," said Edwin Kluter, marketing manager, Integrated Power for Philips Semiconductors, Nijmegen. "This underscores the market acceptance for this product and its qualities. Worldwide, as of today, Philips has sold over 100 million GreenChip ICs that are being applied in all kinds of applications ranging from TV power supplies to notebook adapters."
Meeting customer demand for more integrated, cost-effective power solutions, the TEA1532 is unique in that it combines both QR and CCM modes of operation into one IC with a footprint of SO8 and DIP8. During QR mode operation, the TEA1532 offers true valley switching resulting in improved EMI performance. During CCM operation, it offers the highest power efficiency possible and low standby power levels. In addition to previous GreenChip ICs, the TEA1532 also features a versatile protection pin, brown-out protection and slope compensation, preventing sub-harmonic oscillation in CCM operation. The TEA1532 features easy design, less external components and a high protection level.
Philips TEA1532 offers all of the advantages of the rest of the GreenChip
family including over temperature and over voltage protection for safety,
demagnetization detection, reduced power frequency during standby (less
than 3W), universal mains supply operation (from 70 to 276V AC) and can
be used for power ranges up to 250W. The TEA1532 also offers maximum switching
frequency set to 63kHz and cycle skipping for low standby power levels.
One additional feature is the built-in High Voltage start-up current source
that provides current when needed and which is switched off during normal
operation. With this function, the current level is independent of the input
voltage.
analogZONE Says...
Eliminating unproductive loads such as excessive standby power is one
of the easiest ways to conserve energy, something that benefits both your
customer's bottom line and the environment. The TEA1532 is the latest addition
to the Philips line of "GreenChip" power supply products that
gives designers an easy, cost-effective solution for reducing the standby
load of high-powered printers, set-top boxes, and other products drawing
up to 250 W. This is significant, since current estimates are that up to
10% of domestic electricity is wasted on keeping TVs, VCRs, microwave ovens,
and other devices ready for the one or two hours a day that they are used.
The market issues for high-efficiency supplies are becoming compelling, with reduced operating costs of increasing interest to end users. European sales of some products will only be possible if they meet recently-approved requirements for efficiency and standby power. But even where these mandatory standards don't apply, consumers are becoming much more interested in buying products which meet the efficiency specifications of voluntary eco-labels (EnergyStar, Blue Angel) that are rapidly becoming "must-have" features in consumer goods.
Philips also contends that a "green" supply can save money for a manufacturer. This is because a properly-sized supply is are able to use smaller, less costly inductors, capacitors, diodes, MOSFETs, and other components since they don't have to handle the extra waste energy generated by an inefficient supply.
Like most switching supplies, Philips' GreenChip products offer high efficiency (90% or better) at their rated load, but they also incorporate several clever design features that improve overall power consumption, and add reliability to your product. For starters, all GreenChip devices have a high-voltage startup circuit that gets rid of the inefficient "bleeder" circuit that's usually used to power the supply itself. It also has a somewhat mis-named "power factor pre-conditioner" that uses a pre-boost converter to reduce the amounts of harmonics (generated by the actual switching supply) that are fed back into the power grid. A load sensing circuit reduces the supply's switching frequency when load falls to below 3 W for improved efficiency. In its lowest-power standby mode, it can deliver up to 500 mW to an idling printer, modem, or other product while drawing well under 1 W total. Some devices in the product line can actually switch off their pre-conditioner in a no-load condition to achieve an impressive 300 mW standby power level.
The TEA1532 featured in this review is specifically targeted at the needs of printers, and set top boxes. It can supply up to 250 W to meet the needs of the most power-hungry laser printers. It can also handle lower power levels of smaller printers of 40-60 W. Efficiency varies by output voltage, with around 87% at 12 V and 90%+ at 24 V and above. Other offerings in the product line cover the specific needs of CRTs and TVs, LCD-based TVs and monitors, printers, set top boxes, VCRs/DTRs, and other consumer electronics products. You should note, however, that there are a few applications where these devices are not appropriate. This includes really high-power applications such as home theaters that have extremely "spiky" power demands where transient peak demands can outstrip the baseline load by a factor of 5x or more.
Although it's a bit tangential to this review, I'd like to congratulate Philips on its commitment to actually building sustainable practices into the core of its business, both in the products it offers, and the way it manufactures them. Their GreenChip power supply circuits are only one of a growing number of products that Philips is developing that meet their stringent definition of "green" which reads:
Philips Semiconductors' eco-design policy means that 'green products' can only be called green if they offer one or more of the following: lower energy consumption, use less environmentally hazardous materials, use fewer materials, are easier to recycle and dispose of, or use less packaging.
This is part their overall strategy to run a business that puts green back into our environment, as well as their bottom line. Hopefully you can leverage some of their expertise to do the same for your company with your next power supply design.
The TEA1532 is in production priced at $0.50 10-k piece lots.
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