AK2401 Datasheet, PDF (83/103 Pages) Asahi Kasei Microsystems – Direct Conversion Transceiver

[AK2401]
LNA_TGT_H[5:0]: LNA Gain Mode Switching Threshold (High)
LNA_TGT_L[5:0]: LNA Gain Mode Switching Threshold (Low)
Set LNA gain mode switching threshold of when LNA_AGCOFF bit= “0”<Address0x20>. Threshold
setting corresponds to each PGA gain settings. The setting values must be LNA_TGT_H >
LNA_TGT_L. In case of setting values such as LNA_TGT_H ≤ LNA_TGT_L, the same value set to
LNA_TGT_L will be set to LNA_TGT_H. The difference between LNA_TGT_H and LNA_TGT_L should
be bigger than LNA gain that is decreased by changing to Low gain mode. Here, LNA_TGT_H and
LNA_TGT_L mean PGA gain threshold (dB) not register values.
LNA_TGT_H, LNA_THT_L
[5]
[4]
[3]
[2]
[1]
[0]
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
1
0
0
0
0
0
1
1
・・・
0
1
1
0
1
1
0
1
1
1
0
0
0
1
1
1
0
1
0
1
1
1
1
0
0
1
1
1
1
1
1
0
0
0
0
0
1
0
0
0
0
1
1
0
0
0
1
0
・・・
1
0
1
1
1
1
1
1
0
0
0
0
1
1
0
0
0
1
1
1
0
0
1
0
1
1
0
0
1
1
1
1
0
1
0
0
1
1
0
1
0
1
1
1
0
1
1
0
1
1
0
1
1
1
1
1
1
X
X
X
(X: Do not care)
AGCKP_MODE[1:0]: AGC KEEP Function Operation
Select the operation mode of AGC KEEP function.
Refer to “13.8.9 AGC_KEEP” for details.
PGA Gain
Threshold
Unit
28
27
26
25
・・・
1
0
-1
-2
-3
-4
-5
-6 (default, LNA_TGT_H) dB
・・・
-18 (default, LNA_TGT_L)
-19
-20
Do not use
017003093-E-00
83
2017/3