audio/videoZONE Products for the week of July 2, 2007

National Semiconductor Says . . .
LM49100: Analog Drives Video Experience in Handheld Multimedia Devices
Seven New Display, Audio and Power Management Products Deliver Long-Lasting Video Experience, Superior Sound Quality

Seven new display, audio and power management products from National Semiconductor Corporation enable energy-efficient video in handheld devices such as mobile phones, portable media players and new converged devices that feature phone and media playback functions. The new products perform the "magic" of converting digital data into captivating real-world sights and sounds in the critical subsystems that enable video playback.

In-Stat anticipates growing demand for handheld multimedia devices. By 2011, the market research firm expects the video-enabled handheld device market to grow to 1 billion units from around 300 million in 2006.

Enhancing the Display
The display is the centerpiece of the video experience. National's low-power Mobile Pixel Link (MPL) family of products stream large quantities of data (seen by the user as images, video and graphics) to the display while maximizing battery life. MPL serializes the data to reduce the wire count, which decreases the size of the connector and flexible printed circuit board (flex). MPL reduces electro-magnetic interference (EMI), and its power consumption is roughly half that of competing products. In addition, MPL handles the voltage-level translation between the host and the display, eliminating the need for an external level shifter.

The newest member of National's MPL family, the LM2512 is a high-speed serial host device that supports a video mode interface bridge between the processor and the display. Offered in a 49-bump UFBGA package, the LM2512 is highly programmable, with a unique built-in look-up table that allows for color correction, enabling the designer to optimize the viewing experience in displays offered from multiple manufacturers. The LM2512 also includes a dithering function, which allows 24-bit video to be displayed with high quality on 18-bit displays, preserving the lower power consumption associated with 6-bit RGB data converters.

National's new FPD95120, a high-performance Low Temperature Polycrystalline Silicon (LTPS) display driver, is the narrowest glass-mounted device available for half-VGA format. Just 0.9 millimeters wide, the FPD95120 lets manufacturers maximize the active area of the display glass. The highly integrated driver provides an MPL deserializer, a high-efficiency inductive DC-DC switcher and random access memory (RAM) to enable standby, low-power display capabilities. It also features EEPROM that allows the same device to be used across multiple display manufacturers by storing module calibration data to match color and flicker parameters and the capability to program unique product identification.

Available now, the FPD95120 is offered as Chip-on-Glass (COG) and is $3.40 each in 1,000-unit quantities. The LM2512 is offered in a 40-bump LLP and 49-bump FBGA and is $2.40 each.

Improving Display Backlighting and Color
To optimize the display, backlighting is critical. National's new RGB LED drivers provide better colors on the display and lower power consumption compared to white LEDs. Available in a 25-bump micro SMD package, the LP5520 offers a small and simple solution without the need for optical feedback, producing a true white light over a wide temperature range while improving the color gamut from 70 percent up to 100 percent of the National Television System Committee (NTSC) standard. In adaptive mode, the circuitry in the driver automatically adjusts the output voltage for the lowest possible power consumption. The LP5521, LP5522 and LP55281 color management products feature an assortment of low-power color LED drivers for a variety of handheld lighting applications.

Available now, the LP5520, LP5521, LP5522 and LP55281 range in price from 90 cents to $1.85 each in 1,000-unit quantities.

Generating High-Quality Audio
Superior audio makes a great display even better. National's new LM49100 audio subsystem allows routing of mono voice or stereo music signals to a mono speaker driver or stereo ground-referenced headphone amplifiers (or both) through simple selection of pre-set modes. In addition, it provides layout flexibility through its headphone ground-sensing function. The noise rejection improvement provided by this feature allows designers room to move in space-constrained systems. To maximize battery life, the LM49100 consumes the industry's lowest quiescent current of devices in its class -- less than 5 mA, with all channels active.

Powering Digital Processors
Before video can be displayed, it must be decoded and processed by the application processor. Video processing consumes substantial energy, a major factor limiting battery life on mobile terminals. National's innovative PowerWise technology enables intelligent energy management of the processor using adaptive voltage scaling (AVS). Using National's PowerWise intellectual property integrated onto the processor along with compatible power management ICs such as the LP5552 reduces energy consumption up to 70 percent, extending the life of the battery.

National's LP5552 is an advanced power management IC that supports AVS to enable the processor to adaptively adjust its supply voltage to the minimum level needed, greatly reducing its energy consumption. Offered in a 36-bump micro SMD package, the LP5552 includes two 800 mA buck regulators and five low-dropout regulators (LDOs).

For powering baseband functions, National offers the highly integrated LP3919 power management IC. Offered in a 49-bump micro SMD package, the LP3919 is the smallest integrated power management IC on the market that features high-efficiency switching regulators, LDOs and a battery charger. The LP3919 powers the baseband processor as well as other support circuitry in the system.

Available now, the LP5552 is $4.50 and the LP3919 is $2.35 each in 1,000-unit quantities.

EN-Genius Says...

This is a very sweeping news release, intended to show National's focus on the business of portable products and the new era of video that everyone seems to want displayed on them. The release doesn't really succeed in that business message, because it is neither fish nor fowl to either end of the spectrum of those who want to know. For the investment community there is too much technical information, for the engineering community there is not enough. But within the release there are two products that stand out as deserving of our attention: the LM2512 high-speed serial host which my colleague, Lee Goldberg, will write about shortly, and the LM49100 Boomer amplifier, which I will talk about here.

Before I do, however, (and it is relatively easy to pick holes in the majority of news releases) I have to pull National up on "…producing a true white light over a wide temperature range while improving the color gamut from 70 percent up to 100 percent of the National Television System Committee (NTSC) standard" used in the description of the RGB LED drivers. I have no idea what the intended meaning was, but it is gibberish. A true white light can only be "true" if it is at the defined temperature system standard; there appears to be no understanding of what color gamut is; it was the National Television Standards Committee; there is no NTSC standard -- 525-line color television is defined only by one drawing showing the position of the color burst, and other sync timings, and is more correctly known as RS-170A, replacing the earlier monochrome RS-170.

But on to the LM49100. This is a combination (in National terms "integrated") monophonic speaker amplifier and a stereo headphone amplifier. The story here is that this is the first, I believe, of the combination amplifiers from National to include their "True-Ground" technology on the headphone amplifier. Kudos for first using a charge pump to provide a safe ground for headphone connections goes to the Maxim MAX4410 DirectDrive headphone amplifier that won an analogZONE Product of the Year Award in 2002. That family now lists ten products. The first True-Ground headphone amplifier from National was, I believe, the LM4917 in late 2004 and the family now also includes the LM4982, LM4920 and the LM48821.

The 8 Ω loaded mono speaker amplifier is rated at 1.1 W (1% THD with a 5-V rail) and the 32 Ω loaded stereo headphone amplifier is rated at 30 mW per channel. Gain adjustments for the speaker channel and the two mono channels are separate and controlled on the I2C interface. Each channel has a range from -59 dB to +18 dB, in 32 steps, but the mono channel has an additional 6 dB attenuation before the gain stage. The stereo input is balanced while the mono channels are single-ended. Source modes can be selected after the gain stages and before the final gain stages. The loudspeaker Class-AB stage has a fixed +6 dB gain, while the headphone drivers offer switched 0 dB, -12 dB, -18 dB and -24 dB settings.

National includes its usual pop and click suppression circuits as well as thermal overload protection. The no-load supply current depends on operating mode and the supply rail but the maximum is about 5 mA while shutdown current is about 100 nA. PSRR varies with operational mode, from about 80 dB to 90 dB. CMRR at the magic 217 Hz is a typical 64 dB on the headphone lines and 58 dB on the speaker.

The move to totally safe headphone outputs is to be welcomed in the combined headphone/speaker driver and the market will also embrace it. The LM49100 will do extremely well -- and I applaud its pricing.

The LM49100 is in production in 25 bump GR micro-array priced at $3.35 in 1000-piece lots.

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