IDT92HD90B0X5NLGXYAX IDT, Integrated Device Technology Inc, IDT92HD90B0X5NLGXYAX Datasheet - Page 23

• Manufacturer Part Number: IDT92HD90B0X5NLGXYAX
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of IDT92HD90B0X5NLGXYAX

• Lead Free Status / RoHS Status: Compliant

92HD90
SINGLE CHIP PC AUDIO SYSTEM, CODEC+SPEAKER AMPLIFIER+CAPLESS HP+LDO
IDT CONFIDENTIAL
©2009 INTEGRATED DEVICE TECHNOLOGY, INC.
2.14. EAPD
The EAPD pin (pin 47) is a dedicated, bi-directional control pin. Although named External Amplifier
Power Down (EAPD) by the HD Audio specification, this pin operates as an external amplifier power
up signal. The EAPD value is reflected on the EAPD pin; a 1 causes the external amplifier to power
up (equivalent to D0), and a 0 causes it to power down (equivalent to D3.) When the EAPD value =
1, the EAPD pin must be placed in a state appropriate to the current power state of the associated
Pin Widget even though the EAPD value (in the register) may remain 1. The default state of this pin
is 0 (driving low.) The pin defaults to an open-drain configuration (an external pull-up is recom-
mended.)
Per the HD Audio specification and HDA015-B, multiple ports may control EAPD. The EAPD pin
assumes the highest power state of all the the EAPD bits in all of the pin complexes. The default
value of EAPD is 1 (powered on), but the FG power state will override and the pin will be low. A port
will request External Amp Power Up when its power state is active (FG and pin widget power state is
D1 or D0) or (Analog PC_Beep is enabled and port is enabled as an output) and the port’s EAPD bit
is set to 1. The state of the EAPD pin (unless configured as an input or held low by an external circuit
when configured as an open drain output) will be the logical OR of the external amp power up
requests from all ports.
By default, the EAPD pin also functions as the Mute#/ShutDown# input for the internal BTL amplifier.
In this mode, a low value at the pin (either due to internal EAPD being 0, or to an external entity forc-
ing the pin low) will cause the internal BTL amplifier to mute or enter a low power state depending on
the amplifier configuration. (See below)
Vendor specific verbs are available to configure this pin. These verbs retain their values across link
and single function group resets but are set to their default values by a power on reset:
[6:4]
[3:0]
[7:4]
[3:0]
BitsPerSmpl
NmbrChan
Strm
Ch
Table 8: Mult-channel
23
Bits per Sample
000= 8 bits (not supported)
001= 16 bits
010= 20 bits
011= 24 bits
100-111= Reserved
Number of Channels
Number of channels for this stream in each “sample
block” of the “packets” in each “frame” on the link.
0000=1 channel (not supported)
0001 = 2 channels
1111= 16 channels.
Software-programmable integer representing link
stream ID used by the converter widget. By conven-
tion stream 0 is reserved as unused.
Integer representing lowest channel used by con-
verter.
0 and 2 are valid Entries
If assigned to the same stream, one ADC must be
assigned a value of 0 and the other ADC assigned a
value of 2.
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92HD90