THAT5171 - High-Performance Digital Preamplifier Controller

	THAT5171 Block Diagram

The THAT5171 is a digital gain controller for low-noise, analog, differential, current-feedback audio preamplifiers such as the THAT1570. When used in conjunction with an appropriate analog gain block, the 5171 can set gain to 5.6dB, or any gain from 13.6dB to 68.6dB in 1dB steps, while preserving low noise and distortion. It operates from ±5V to ±17V supplies, supporting input signal levels as high as +22 dBu (at 5.6dB gain, and ±17V supplies) in combination with the 1570 (without an external input pad). The 5171 includes a differential servo and zero-crossing detector to minimize dc offsets and glitches (zipper noise) during gain adjustments.

The 5171 is controlled via an addressable serial-peripheral interface (SPI) port. Four General Purpose Outputs (GPOs) can be controlled via this interface. The GPOs may be connected to input pads, analog switches, mute circuits, LEDs, etc. The SPI bus supports read-back so that host software can verify proper operation.

The 5171 was designed to mate perfectly with the THAT1570 Differential Audio Preamplifier IC. Together, these two ICs provide a best-of-class solution for digitally-controllable audio preamplifier applications. However, for designers who prefer a more customized solution, the 5171 may also be used to control a discrete preamplifier.

Fabricated in a high-voltage CMOS process, the 5171 integrates an astonishing amount of circuitry within a very small package. It comes in a small (7x7 mm) 32-pin QFN package, making it suitable for small portable devices.

Features Ideal mate for THAT1570 preamplifier Wide gain range: +13.6 to +68.6dB in 1dB steps and +5.6dB Wide supply range: ±5V to ±17V Wide output swing:+27dBu (±17V sup.) Wide input swing: +22dBu (±17V sup.) Low THD+N: 0.0003% @ 22dB gain Integrated differential servo minimizes output offset Zero-crossing detector minimizes switching noise Flexible, addressable SPI interface Four general-purpose digital outputs Small 7mm x 7mm QFN32 package

Applications Digitally controlled microphone preamplifiers Digitally-controlled instrumentation amplifiers Digitally-controlled differential amplifiers Audio mixing consoles PC audio breakout boxes Audio distribution systems Digital audio snakes Portable audio recorders

For complete specifications, download a copy of the 5171 Datasheet. Datasheets are provided in Adobe's PDF format. You need to have Adobe Acrobat Reader installed on your computer to view the file. To obtain a free copy of Acrobat Reader follow the link at right.

Model	Package	Pricing (1000)	Part Number	Min Order Quantity	Reference
5171	32 Pin QFN	$6.70 USD	5171N32-U	46	Datasheet RoHS Info
	32 Pin QFN Tape and Reel	**	5171N32-UR	2000

All 5171 parts are RoHS compliant.
Minimum Order Quantity is one tube full. Parts must be ordered in multiples of the MOQ.
Samples are available for qualified applicants.
Pricing is subject to change.

**All models are available on tape and reel for a modest increase in price and require an extended lead time. Tape and reel parts have a 2000 piece minimum and must be ordered in multiples of 2000. Please contact our sales department for pricing and delivery.

The THAT5171 is designed to mate perfectly with THAT's 1570 Low-Noise Differential Preamplifier IC to create an optimized, Digitally Controlled Audio Preamplifier. A demonstration system is available for this 1570/5171 combination. The THAT Digitally-Controlled Mic Preamp Demo Board allows developers to evaluate the performance of the THAT1570 / THAT5171 ICs in a typical application. The demo board provides a balanced audio input on a Neutrik "combo" connector with 48V phantom power, and a balanced audio output on XLR and ¼" TRS connectors. The supplied graphical user interface (GUI) controls all functions in the 5171 chip via USB. A prototyping area is available for adding new circuitry, or modifying existing circuitry. For more information open the 1570/5171-Demo User's Guide or contact sales at the address below.

For questions, samples or further pricing information, please contact us directly by telephone: +1(508)634-9922, fax:+1(508)634-6698, or email: sales@thatcorp.com.