ak4648 AKM Semiconductor, Inc., ak4648 Datasheet - Page 74

• Manufacturer Part Number: ak4648
• Description: Stereo Codec With Mic/hp/spk-amp
• Manufacturer: AKM Semiconductor, Inc.

<Connection with mono headphone>
The AK4648 can be connected with mono headphone by using Headphone-Amp power management bit and HPZ bit. As
right channel of mono headphone is usually connected to GND, the right channel of Headphone-Amp must be Hi-Z. Here
are the power up sequence in Single-ended Mode and Pseudo Cap-less Mode.
1. Single-ended Mode
2. Pseudo Cap-less Mode
MS0625-E-01
(1) Power-down Headphone-amp: PMHPL=PMHPR=HPZ bits = “0”
(2) Power-up left channel of Headphone-amp: PMHPL = “1”
(3) Change pull-down resistor of right channel of Headphone-amp: HPZ bit = “1”
(4) Release mute of Headphone-amp: HPMTN bit: “0”
(1) Power-down of Headphone-amp: PMHPL=PMHPR=PMHPC=HPZ bits = “0”
(2) Power-up left channel and common buffer of Headphone-amp: PMHPL = PMHPC bits = “1”
(3) Change pull-down resistor of right channel of Headphone-amp: HPZ bit = “1”
(4) Release mute of Headhone-amp: HPMTN bit: “0”
HPL/HPR pins output VSS2.
Left channel of Headphone-amp is powered-up and HPL pin outputs VSS2.
HPR pin is pulled-down by 200k Ω (typ.) to VSS2.
HPL pin outputs the signal and HPR pin is pulled-down by 200k Ω (typ.) to VSS2.
HPL/HPR/HVCM pins output VSS2.
Left channel and common buffer of Headphone-amp are powered-up and they output VSS2.
HPR pin is pulled-down by 200k Ω (typ.) to VSS2.
HPL pin outputs the signal. HPR pin is pulled-down by 200k Ω (typ.) to VSS2 and outputs HVCM voltage.
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[AK4648]
2007/06