Archive Feedback

1W CMOS Power Amplifier In Space Saving Mini SO-8 Package Provides Excellent Sound Quality in Portable Audio Applications

The manufacturer says . . .

ChipCenter's Paul O'Shea says . . .

Fairchild Semiconductor International announces the FAN7023, a CMOS power amplifier for mobile phone, PDA and portable audio systems. The FAN7023 is a monaural power amplifier available in both a space-saving, mini SO-8 and an SO-8 package. When delivering 1.0W of continuous RMS power into an 8ohm speaker at 5V supply, the FAN7023 typically has 0.1% of THD+N (Total Harmonic Distortion plus Noise). The FAN7023 operates from 2.2V to 5.5V supply. The amplifier's superior THD and PSRR (Power Supply Rejection Ratio, typically 65dB) characteristics guarantee high output performance. With low supply current characteristics and shutdown function, as well as low shutdown current consumption (0.1 microamp, typical), the FAN7023 is well suited for battery-powered portable applications requiring energy savings and a long battery life. The FAN7023 features thermal shutdown protection, unity gain stability and external gain configuration capability. Board space is reduced because designs using the FAN7023 do not need an output coupling capacitor, bootstrap capacitor or a snubber network. Complementing the FAN7023 is a broad array of Fairchild's signal path solutions ranging from high-performance, low power operational amplifiers to analog switches that provide optimum performance with a minimum power budget. Fairchild Semiconductor International (NYSE: FCS) is a leading global supplier of high performance products for multiple end markets. With a focus on developing leading edge power and interface solutions to enable the electronics of today and tomorrow, Fairchild's components are used in computing, communications, consumer, industrial and automotive applications. Fairchild's 10,000 employees design, manufacture and market power, analog & mixed signal, interface, logic, and optoelectronics products from its headquarters in South Portland, Maine, USA and numerous locations around the world. Fairchild Semiconductor Customer Support Group; Tel: 888-522-5372, Fax 972-910-8036. Web site: www.fairchildsemi.com.

The trends today for applications like cell phones and PDAs are moving toward miniaturization and better performance with lower power. The FAN7023 helps reduce the board space requirements by further enhancing the existing Fairchild products with the mini-small outline package and the molded leadless package. The FAN7023 is a drop-in replacement for the company's previously released FAN7021 but in a much smaller package size and with improved total harmonic distortion (THD) performance. Initially, Fairchild introduced the FAN 7000 series of audio amps for Discman CD applications in a 10-lead Thin Small Outline Package (TSOP). Since then the company moved to an 8-lead SOP and also an 8-lead mini SOP package. The FAN7021, originally offered for the cordless telephone in the SOP package, is now enhanced with the FAN7023, which improves the noise performance. Both of them are 1 W amps but the FAN7023 comes in a much smaller 10-lead min lead package and offers signal-to-noise ratio, THD, and Power Supply Rejection Ratio improvements over the FAN7021. The FAN7023 also enhances the noise performance compared to the competition. The FAN7023 and the company's other power amp products offer a pin-compatible replacement for many of its competitors. However, this product also provides enhanced noise performance and lower quiescent current, for extended battery life - the driving force for many portable and wireless products. As I was reviewing the data sheet I noticed that the shutdown current in the press release says that it is 0.1 uA but the data sheet says it is 0.01 uA - a significant difference. The company has assured me that the data sheet is correct. That's really low and important because if you look at the speaker amp on cell phones, cordless phones, and PDAs, typically they operate in the shutdown mode when there isn't an audio output. Reducing the power will help extend the battery life, which is a significant advantage of this product. The total harmonic distortion spec states that it is higher with a lower voltage than with a higher voltage. For example the 2.6 V version of the product has a higher THD than the 5 V version. That occurs because there is some noise that is not voltage or performance related. THD is measured compared to output power. If you look at the 3.3 V version of the product it is 0.25 W, and for 2.6 V the measurements are down at 0.2 W. Consequently, there is a fixed amount of noise. Yet, if you compare it to a smaller amount of total output power you will see (as a result of the measurement conditions) that the THD percentage will be higher on the lower voltage amp. Fairchild offers a power supply rejection ratio of 70 dB which is an important spec. It is about 2 or 3 dB better than the competition. Every 3 dB is a factor of 2, so if you look at 67 dB vs. 70 dB it means that it has a 2x better power supply rejection ratio. These are drop-in replacements for many competitive parts with better performance specs. Designers who aren't currently using the FAN7000 series amps will want to make this a second-source part. As part of Fairchild's Customer First eBusiness Program, samples of the FAN7023 may be ordered online directly from the product folder. Price: US $0.57 in 1,000-piece quantities; Availability: Now; Delivery: 8-10 weeks ARO Datasheet

		Click here to get your listing up.