Features

Direct path #8482;- Eliminate banging and clicks

-On eliminates output DC blocking capacitors

--3- V to 3.6-V power supply voltage

low noise and THD

--1 × gain signal-to-noise ratio gt; 105 db

--vn lt; 20 Hz to 20 kHz, –1 × gain (typical value)

—Thd+n lt; 0.003%, load is 10-kΩ, and the gain is -1 ×

2-vRMS output voltage to 600Ω load

single-end input and single-end output

× gain value

Edible mute, attenuation exceeds 80 dB

short circuit and heat protection

± 8-kv HBM ESD protective output

Application

Plasma display and LCD TV

DVD player

micro and and and and the miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature and and miniature. Micro combination system

sound card

Description

DRV612

is a single-end, 2-vRMS stereo sound line drive, aiming to reduce Number of components, circuit board space and cost. For single -power electronic devices for size and cost is the ideal choice for the single power supply electronic equipment of key design parameters.

DRV612 does not require a power supply greater than 3.3V to generate its 5.6-VPP output, nor does it need to be railled.

The DRV612 device is designed with DirectPath technology of the TI patent. This technology integrates the charge pump to generate a negative power rail and provide a clean, non -POP ground bias output. DRV612 can drive 2 virtual machines into 600Ω load. DirectPath technology also allows removal of expensive output DC blocking capacitors.

The device has a fixed gain single -end input and gain selection pin. Use a resistor on this pin. The designer can choose from the 13 internal programmable gain settings to make the line driver match with the output level of the codec. The device also reduces the number of components and circuit board space.

The output of the line has a protection of ± 8-KV HBM ESD to achieve a simple ESD protection circuit. DRV612 has a built -in active and mute control, with an attenuation of more than 80 decibels,Can achieve no mute switch control.

DRV612 has 14 stitches TSSOP and 16 -pin VQFN. For stereo headphones drivers with both encapsulation shapes, see TPA6139A2.

Equipment information

(1), please refer to the appointment appendix at the end of the data table.

Function box diagram

Typical features

vdd 3.3 V, TA 25 ° C, RL 2.5 k #8486 ;,, CPUMP C (VSS) 1 μF, gain --2 v/v (unless there is another instructions).

Parameter measurement information All parameters are measured according to the conditions described in the specification.

Detailed instructions

Overview

DRV612 is a direct path stereo line drive. It does not require output DC blocking capacitors, and can transmit 2 VRMs to 600Ω load. The device has a built -in POP inhibitory circuit, which can completely eliminate the POP noise when booting and shutting down. The amplifier output has short circuit protection.

DRV612 gain is controlled by the external resistor RGAIN. The recommended value is set to the gain setting.

DRV612 is powered from a 3-V to 3.6-V, because it uses a built-in charge pump to generate a negative voltage source for the line drive.

Function box diagram

Feature description

line driver amplifier

Single -electric source line driver amplifier usually needs DC blocking Capacitor. The above figure in FIG. 8 illustrates the connection between the traditional line drive amplifier and the load and output signal.

The value of the DC closed lock capacitor is usually very large. In the process of power, a quiet circuit is required to minimize the clicks and banging sounds as much as possible. Output capacitors and mute circuits consume PCB area, increase assembly costs, and reduce the preservation of audio output signals.

Direct channel amplifier structure runs from a single power supply, but uses internal charge pumps to provide negative voltage tracks.

Combined with the positive track provided by the user and the negative IC, the equipment runs in an effective division mode.

The output voltage is now concentrated in zero, which can swing to the right or negative. Combined with the built -in clicks and pop -up reduction circuits, the direct path releases large instruments without output DC blocking capacitors.

The bottom box diagram and waveform of FIG. 8 illustrates the ground reference line driver architecture. This is the body of DRV612The system structure.

Equipment function mode

Internal under voltage detection

DRV612 contains an internal accurate band -reference voltage and a comparator used to monitor the VDD of the power supply voltage. The internal VDD monitor is set to 2.8 V, lagging behind 200 MV.

No pop -up power supply

During the rise and decrease of the power supply, it is at a low position by maintaining a mute pin to ensure that there is no pop -up power supply. The pin should be kept at a lower level, until the input AC coupling convergence container is fully charged, and then the mute pin is high, so that the AC coupling can be properly charged, thereby achieving non -pop -up power power. Figure 10 illustrates priority.

Application and implementation

Note

The information in the following application chapters is not part of the TI component specification. TI does not guarantee its accuracy Or integrity. TI's customers are responsible for determining the applicability of the component. Customers should verify and test their design implementation to confirm the system function.

Application information

DRV612 starts its operation by asserting the mute pin as logical 1. When the low mute pin is pulled, the device enters the mute mode. The charge pump generates a negative power supply voltage. The charge pump flying capacitor connected between CP and CN transmits the charge to generate a negative power supply voltage. The output voltage can generate positive and negative voltage fluctuations, and the center is close to 0 volts, and no output capacitor is required. The input coupling container stops any DC bias from the audio source and ensures the maximum dynamic range.

This typical connection diagram emphasizes the external component and system -level connection required for the normal operation of the device in the popular use case. TI can support any design changes through the schematic diagram and layout. Access E2E. If the Texas Instrument needs to design help, please join the audio amplifier discussion forum to obtain more information.

Capacity load

DRV612 can directly drive high capacitance loads up to 220 PF. By adding a 47 or a larger series resistor to the line drive, you can accept a higher capacitance load.

Typical application

Design requirements

Table 1 lists the design parameters of this application instance.

Detailed design program

Part

charge pump flying capacitor and VSS capacitor

charge pump flying capacitor for flying capacitors Transfer charge during the negative power supply voltage. VSS capacitors must be at least equal to the charge pump capacitor to allow maximum charge transfer. Low ESR capacitor is an ideal choice, and 1 μF is a typical value.

Drumpy capacitor

DRV612 is a direct path line driver amplifier, which requires sufficient power supply to ensure that the noise and total harmonic distortion (THD) is low. A good low -equate series resistance (ESR) ceramic capacitor is usually 1 μF, placed at the place where the VDD lead is as close to the device, and the effect is the best. Putting this off -coupled container near DRV612 is important for the performance of the amplifier. In order to filter a low -frequency noise signal, it is also helpful to place a 10μF or larger capacitor near the audio power amplifier, but it does not need it in most applications, because the PSRR of this device is very high.

gain settings

Programming the gain setting with gain pins. The gain is locked during the power -power period. Table 2 lists gain settings.

Note

If the gain of the gain is not connected (open), select the default gain-2 times.

Input the lock -locking capacitor

DC input blocking capacitors need to be connected to the input pin of DRV612 with the audio signal. These capacitors block the DC parts of the audio source and allow DRV612 to input appropriate bias to provide maximum performance. The input blocking capacitor also limits the DC gain to 1 to limit the data offset voltage at the output terminal.

These capacitors and input resistance RIN form high -pass filter. The deadline is calculated with Formula 1. For this calculation, the capacitor used is input blocking capacitors, and the resistance is the input resistance selected from Table 3. When one of the two values u200bu200bis given, the frequency and/or capacitance can be determined.

For the fixed cut -off frequency of 2 Hertz, the size of the input capacitor is as shown in Table 3, and the capacitor fourth houses enter the closest E6 value. For the 20Hz deadline, the capacitance value is only 10; for example, for 1 × gain, 150 nf is required.

Power recommendation

This device is designed at 3V to 3.6V input voltage. Therefore, the output voltage range of the power supply should be within this range , And should be well adjusted. TI recommends placing the decoupled capacitor on the feet of each voltage source. Through these decoupled power containers as close to DRV612 as possible.

Layout

Layout Guide

The ground trajectory is recommended as a star-ground wiring to minimize the buzz interference. VDD and VSS off -coupled capacitors and charge pump power containers must be connected with short trajectories.

Compatible with TPA6139A2

DRV612 stereo line driver and headset amplifier TPA6139A2 pins. Therefore, a single PCB layout can be together with the fill optionUsed for different board configurations.

layout example