Tr i p ath Technol ogy, I n c. - Techni cal I n for m ati on

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RB-TK2051 – Rev. 1.0/06.02

JUMPER SETTINGS

There is a 3-pin header for the MUTE control of the TK2051. With the jumper placed in the G5 position the

system is un-muted. When the jumper is placed in the V5 position the mute pin is pulled high (5V) and the

amplifiers are muted. Please refer to the Board Connection Diagram for the connector locations on the

RB-TK2051.

OUTPUT OFFSET NULL

There are six potentiometers that are used to manually trim the output offset to 0Vdc. Please refer to the

Board Connection Diagram for the potentiometer locations on the RB-TK2051. The Evaluation board is

shipped with the offsets nulled within +/-10mV.

GAIN SETTING

The gain of the RB-TK2051 Rev 2.2 is set to 15V/V. The gain of the TK2051 is the product of the TC2000

(control stage) gain and the TP2051 (power stage) gain. The control stage gain is set to unity. Before

changing the gain of the RB-TK2051, please refer to the Amplifier Gain section of the TK2051 Data Sheet.

Performing Measurements on the EB-TK2051 Rev 1.3:

The TK2051 operates by generating a high frequency switching signal based on the audio input. This

of the switching pattern is spread spectrum in nature and typically varies between 100kHz and 1MHz,

which is well above the 20Hz – 20kHz audio band. The pattern itself does not alter or distort the audio

input signal, but it does introduce some inaudible components.

The measurements of certain performance parameters, particularly noise related specifications such as

THD+N, are significantly affected by the design of the low-pass filter used on the output as well as the

bandwidth setting of the measurement instrument used. Unless the filter has a very sharp roll-off just

beyond the audio band or the bandwidth of the measurement instrument is limited, some of the inaudible

noise components introduced by the TK2051 amplifier switching pattern will degrade the measurement by

including out of band (audio) energy.

One feature of the TK2051 is that it does not require large multi-pole filters to achieve excellent

performance in listening tests, usually a more critical factor than performance measurements. Though

using a multi-pole filter may remove high-frequency noise and improve THD+N type measurements (when

they are made with wide-bandwidth measuring equipment), these same filters degrade frequency

response. The RB-TK2051 has a simple two-pole output filter with excellent performance in listening

tests.

(See Application Note 4 for additional information on bench testing)