TAS2020 datasheet(22/79 Pages) TI2

22 / 79 page

Table 6-17. Class-D output edge rate control

CLASSD_OUTPUT_EDGERATE

_CTRL[1:0]

Configuration

Class-D output edge rate of

0.5V/ns

Class-D output edge rate of

1.0V/ns

Reserved

11(default)

Class-D output edge rate of

2V/ns

The class-D amplifier has over current protection on each of the output power FETs, including the PVDD High

side and the ground power FETs.

The class-D amplifier output impedance can be controlled when the outputs stop switching during Noise gate

mode using CLASSD_HIZ_MODE control register.

Table 6-18. Class-D high-Z mode control

CLASSD_HIZ_MODE

Configuration

0 (default)

Output pulled down with 2.5kΩ

Output pulled down with >13kΩ

6.4.2.4 Supply Tracking Limiters with Brown Out Prevention

TAS2020 monitors class-D supply voltage along with the audio signal to automatically decrease gain when the

audio signal peaks exceed a programmable threshold. This helps prevent clipping and extends playback time

through end of charge battery conditions. The limiter and brown out module calculates the signal attenuation

required based on the condition of the signal level, channel gain and the selected supply voltage.

The Brown Out Prevention (BOP) module provides a priority input to provide a fast response to transient dips

in the battery supply. The BOP feature can be enabled by configuring the register bit BOP_EN high. When

the selected supply dips below the brown-out threshold configured by setting register BOP_THR_LVL[23:0],

the BOP begins reducing gain. The rate of gain reduction (db/sample) can be configured by setting the

BOP_ATK_RATE[23:0] registers. When the supply voltage rises above the brownout threshold, the BOP begins

to release the gain after the programmed hold timer, BOP_HLD_COUNT[23:0]. The BOP feature uses the

LIM_RLS_RATE[23:0] register setting to release after a brown out event. The release rate is rate of gain

increase in db/sample ratio. During a BOP event the limiter updates is paused. This is to prevent a limiter from

releasing during a BOP event.

The device can be configured to hold the gain attenuation once a BOP event is detected by setting the register

bit BOP_INF_HLD high. When the bit is programmed high, the Limiter and BOP module does not release the

gain attenuation and holds the device in the programmed min gain attenuation level until the infinite hold is

cleared by setting the register bit BOP_HLD_CLR high. The hold clearing bit is self clearing and automatically

resets to low state once the hold is cleared.

A hard brownout level can be set to shutdown the device if the BOP gain attenuation cannot mitigate the drop

in battery voltage. The brown out based shutdown of the device is enabled when BOPSD_EN bit is set high

and shuts down when the battery voltage falls below the voltage threshold set by BOSD_THR_LVL[23:0] register

bits.

A maximum level of attenuation applied by the limiters and brown out prevention feature is configurable via the

LIM_MAX_ATN register. This attenuation limit is shared between the features. For instance, if the maximum

attenuation is set to 6dB and the limiters have reduced gain by 4dB, the brown out prevention feature is only

able to reduce the gain further by another 2dB. If the limiter or brown out prevention feature is attacking and

reaches the maximum attenuation, gain is not reduced any further.

TAS2020

SLASFD4A – AUGUST 2024 – REVISED JULY 2026

www.ti.com

Submit Document Feedback

Product Folder Links: TAS2020

TAS2020 Datasheet(PDF) 22 Page - Texas Instruments

TAS2020 Datasheet(HTML) 22 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79

Datasheet Download

Link URL