Cirrus Logic CS42L52 - Manual (Page 72)

72 DS680F2
CS42L52
3/1/13
6.37.3 VP Reference
Sets the desired VP reference used for battery compensation.
6.38 VP Battery Level (Address 30h) (Read Only)
6.38.1 VP Voltage Level (Read Only)
Indicates the unsigned VP voltage level.
6.39 Speaker Status (Address 31h) (Read Only)
6.39.1 Speaker Current Load Status (Read Only)
Indicates whether or not any of the speaker outputs is shorted to ground.
VPREF[3:0] Desired VP used to calculate the required attenuation on the speaker output:
(for VA = 1.8 V)
0000 1.5 V
0001 2.0 V
0010 2.5 V
0011 3.0 V
0100 3.5 V
0101 4.0 V
0110 4.5 V
0111 5.0 V
(for VA = 2.5 V)
1000 1.5 V
1001 2.0 V
1010 2.5 V
1011 3.0 V
1100 3.5 V
1101 4.0 V
1110 4.5 V
1111 5.0 V
Application: “VP Battery Compensation” on page 33
7 6 5 4 3 2 1 0
VPLVL7 VPLVL6 VPLVL5 VPLVL4 VPLVL3 VPLVL2 VPLVL1 VPLVL0
VPLVL[7:0] VP Voltage
...
0101 1110 3.0 V (for VA = 2.0 V); apply formula using actual VA voltage to calculate VP voltage.
...
0111 0010 3.7 V (for VA = 2.0 V); apply formula using actual VA voltage to calculate VP voltage.
...
Formula: VP Voltage = (Binary representation of VPLVL[7:0]) * VA / 63.3
7 6 5 4 3 2 1 0
Reserved Reserved SPKASHRT SPKBSHRT SPKR/HP Reserved Reserved Reserved
SPKxSHRT Speaker Output Load
0 No overload detected
1 Overload detected