ZHCSBC3F July 2013 – February 2020 TAS5760M
PRODUCTION DATA.
For systems which do not require the added flexibility of the I²C control port or do not have an I²C host controller, the TAS5760M can be used in Hardware Control Mode. In this mode of operation, the device operates in its default configuration and any changes to the device are accomplished via the hardware control pins, described below. The audio performance between Hardware and Software Control mode is identical, however more features and functionality are available when the device is operated in Software Control mode. The behavior of these Hardware Control Mode pins is described in the sections below.
Several static I/O's are present on the TAS5760M which are meant to be configured during PCB design and not changed during normal operation. Some examples of these are the GAIN[1:0] and PBTL/SCL pins. These pins are often referred to as being tied or pulled LOW or tied or pulled HIGH. A pin which is tied or pulled LOW has been connected directly to the system ground. The TAS5760M is configured such that the most popular use cases for the device (that is BTL mode, 768-kHz switching frequency, and so forth) require the static I/O lines to be tied LOW. This ensures optimum thermal performance as well as BOM reduction.
Device pins that need to be tied or pulled HIGH should be connected to DVDD. For these pins, a pull-up resistor is recommended to limit the slew rate of the voltage which is presented to the pin during power up. Depending on the output impedance of the supply, and the capacitance connected to the DVDD net on the board, slew rates of this node could be high enough to trigger the integrated ESD protection circuitry at high current levels, causing damage to the device. It is not necessary to have a separate pull-up resistor for each static digital I/O pin. Instead, a single resistor can be connected to DVDD and all static I/O lines which are to be tied HIGH can be connected to that pull-up resistor. This connectivity is shown in the Typical Application Circuits. These pullup resistors are not required when the digital I/O pins are driven by a controlled driver, such as a digital control line from a systems processor, as the output buffer in the system processor will ensure a controlled slew rate.