WM8962B datasheet(198/295 Pages) WOLFSON

198 / 295 page

WM8962

198

Rev 4.3

THERMAL SHUTDOWN

The WM8962 incorporates a temperature sensor on each of the headphone circuit and the speaker

circuit. These detect when the device temperature is within normal limits, or the device is approaching

a hazardous temperature condition (above 125ºC and below 145ºC), or if the device has exceeded a

hazardous temperature condition (>145ºC). The temperature sensors can be configured to

automatically disable the audio outputs of the WM8962 in response to an over-temperature condition

(approximately 145ºC) on either the headphone or the speaker circuits.

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

Input/Output (GPIO)

” section. The temperature sensor can also be used to generate Interrupt events,

as described in the “Interrupts” section.

The temperature sensors are enabled on the headphone and the speaker circuits by setting the

TEMP_ENA_HP and the TEMP_ENA_SPK register bits respectively.

Temperature warnings are flagged at 125ºC by asserting the TEMP_WARN_HP (headphones) and

TEMP_WARN_SPK (speakers) register bits. Potentially hazardous over-temperature conditions are

flagged by the setting of the TEMP_ERR_HP (headphones) and TEMP_ERR_SPK (speakers)

registers.

When the THERR_ACT register is also set, then a device over-temperature condition in either sensor

(TEMP_ERR_HP or TEMP_ERR_SPK asserted) will cause the speaker outputs (SPKOUTL and

SPKOUTR) to be disabled by setting SPKL_ENA and SPKR_ENA to 0, and the headphone outputs to

be disabled by setting CP_ENA to 0. This response is likely to prevent any damage to the device

attributable to the large currents of the output drivers. Note that headphone and speaker audio outputs

are both disabled when either of the TEMP_ERR_HP or TEMP_ERR_SPK register bits is set.

When the audio circuits are disabled by THERR_ACT after reaching a temperature of 145ºC, they will

be reset to their previous setting once the temperature drops again.

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

R23 (17h)

Additional

control(1)

THERR_ACT

[15:0]

Speaker and Headphone

over-temperature shutdown enable.

0 = Disabled

1 = Enabled

Note that TEMP_ENA_HP or

TEMP_ENA_SPK or both must be

enabled for Automatic Shutdown to work

R47 (2Fh)

Thermal

Shutdown

Status

TEMP_ERR_

Headphone temperature error status

(triggered at 145°C)

0 = Not triggered

1 = Triggered

Note that this is a Read Only field

TEMP_WARN

_HP

Headphone temperature warning status

(triggered at 125°C)

0 = Not triggered

1 = Triggered

Note that this is a Read Only field

TEMP_ERR_

SPK

Speaker temperature error status

(triggered at 145°C)

0 = Not triggered

1 = Triggered

Note that this is a Read Only field

TEMP_WARN

_SPK

Speaker temperature warning status

(triggered at 125°C)

0 = Not triggered

1 = Triggered

Note that this is a Read Only field

R48 (30h)

TEMP_ENA_

Headphone temperature sensor enable

0 = Disabled

1 = Enabled

WM8962B Datasheet(PDF) 198 Page - Wolfson Microelectronics plc

WM8962B Datasheet(HTML) 198 Page - Wolfson Microelectronics plc

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 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL