WM1811A datasheet(214/328 Pages) WOLFSON

214 / 328 page

WM1811A

Production Data

PD, November 2013, Rev 4.1

214

THERMAL SHUTDOWN

The WM1811A incorporates a temperature sensor which detects when the device temperature is

within normal limits or if the device is approaching a hazardous temperature condition. The

temperature sensor can be configured to automatically disable the audio outputs of the WM1811A in

response to an overtemperature condition (approximately 150ºC).

The temperature status can be output directly on a GPIO pin, as described in the “General Purpose

Input/Output” section. The temperature sensor can also be used to generate Interrupt events, as

described in the “Interrupts” section. The GPIO and Interrupt functions can be used to indicate either a

Warning Temperature event or the Shutdown Temperature event.

The temperature sensor is enabled by setting the TSHUT_ENA register bit. When the TSHUT_OPDIS

is also set, then a device over-temperature condition will cause the speaker outputs (SPKOUTL and

SPKOUTR) of the WM1811A to be disabled; this response is likely to prevent any damage to the

device attributable to the large currents of the output drivers.

Note that, to prevent pops and clicks, TSHUT_ENA and TSHUT_OPDIS should only be updated

whilst the speaker and headphone outputs are disabled.

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

R2 (0002h)

Power

Management

(2)

TSHUT_ENA

Thermal sensor enable

0 = Disabled

1 = Enabled

TSHUT_OPDIS

Thermal shutdown control

(Causes audio outputs to be disabled

if an overtemperature occurs. The

thermal sensor must also be enabled.)

0 = Disabled

1 = Enabled

Table 131 Thermal Shutdown

WM1811A Datasheet(PDF) 214 Page - Wolfson Microelectronics plc