Abov MC97F60128 - Programmable Gain Controller

296
MC97F60128
ABOV Semiconductor Co., Ltd.
11.15.5 Programmable Gain Controller
There are 11 selectable step in the programmable gain controller. The steps are -30dB, -24dB, -18dB, -12dB, -6dB,
0dB, +6dB, +12dB, +18dB, +24dB and +30dB. The gain is selected by the programmable gain register (PGSR).
The gain controller converts the value of the DACDR[15:0] by the following procedure.
− Get the value of the D/A converter data register (DACDR[15:0])
− Change the data into a 16-bit signed format
− Adjust the data by a selected gain
− Modify the data into a 16-bit binary format
− Write the data to the D/A converter buffer register (DACBR[15:0])
FFFFH
8000H
0000H
DACDR[15:0]
FFFFH
8000H
0000H
DACBR[15:0]
FFFFH
8000H
0000H
DACBR[15:0]
FFFFH
8000H
0000H
DACBR[15:0]
PGSR = 05H [0dB] PGSR = 06H [+6dB]
PGSR = 04H [-6dB] PGSR = 07H [+12dB]
DACDR[15:0] = DACBR[15:0]
Figure 11.85 The DACBR[15:0] Value by a Selected Gain