WM1811A datasheet(138/328 Pages) WOLFSON

Part #	WM1811A

Description	Multi-Channel Audio Hub CODEC for Smartphones

PDF	328 Pages

Scroll/Zoom	100%

Manufacturer	WOLFSON [Wolfson Microelectronics plc]

Direct Link	http://www.wolfsonmicro.com

Logo

138 / 328 page

WM1811A

Production Data

PD, November 2013, Rev 4.1

138

The measurement accuracy of the microphone detect function is assured whenever the connected

load is within the applicable limits specified in the “Electrical Characteristics”. Note that a 2.2k

 (2%)

resistor must also be connected between MICDET and MICBIAS2.

Note that the connection of a microphone will change the measured impedance on the MICDET pin;

see “Applications Information” for recommended components for typical applications.

The measurement time varies between 100

s and 500s according to the impedance of the external

load. A high impedance will be measured faster than a low impedance.

The timing of the microphone detect function is illustrated in Figure 42. Two different cases are

shown, according to whether MICBIAS2 is enabled periodically by the impedance measurement

function (MICB2_ENA=0), or is enabled at all times (MICB2_ENA=1).

Figure 42 Microphone Detect Timing

WM1811A Datasheet(PDF) 138 Page - Wolfson Microelectronics plc