SA58646 Datasheet, PDF (17/42 Pages) NXP Semiconductors – UHF 900 MHz transceiver IC

NXP Semiconductors
SA58646
UHF 900 MHz transceiver IC
SA58646_1
Product data sheet
Table 9.
Select
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
TX and RX gain
RX_GAIN[4:0] and TX_GAIN[4:0]
Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0
0
0
0
0
0
0
0
0
1
0
0
0
1
0
0
0
0
1
1
0
0
1
0
0
0
0
1
0
1
0
0
1
1
0
0
0
1
1
1
0
1
0
0
0
0
1
0
0
1
0
1
0
1
0
0
1
0
1
1
0
1
1
0
0
0
1
1
0
1
0
1
1
1
0
0
1
1
1
1
1
0
0
0
0
1
0
0
0
1
1
0
0
1
0
1
0
0
1
1
1
0
1
0
0
1
0
1
0
1
1
0
1
1
0
1
0
1
1
1
1
1
0
0
0
1
1
0
0
1
1
1
0
1
0
1
1
0
1
1
1
1
1
0
0
1
1
1
0
1
1
1
1
1
0
1
1
1
1
1
RX and TX gain Earpiece output
(dB)
(dB)
−7.5
−15.0
−7.0
−14.0
−6.5
−13.0
−6.0
−12.0
−5.5
−11.0
−5.0
−10.0
−4.5
−9.0
−4.0
−8.0
−3.5
−7.0
−3.0
−6.0
−2.5
−5.0
−2.0
−4.0
−1.5
−3.0
−1.0
−2.0
−0.5
−1.0
0
0
+0.5
+1.0
+1.0
+2.0
+1.5
+3.0
+2.0
+4.0
+2.5
+5.0
+3.0
+6.0
+3.5
+7.0
+4.0
+8.0
+4.5
+9.0
+5.0
+10.0
+5.5
+11.0
+6.0
+12.0
+6.5
+13.0
+7.0
+14.0
+7.5
+15.0
+8.0
+16.0
The TX and RX audio signal paths each have a programmable gain block. If a TX or RX
voltage gain other than the nominal power-up default is desired, it can be programmed via
the microcontroller interface. The gain blocks can be used during final test of the radio to
electronically adjust for gain tolerances in the radio system. The RX and TX gain have
steps of 0.5 dB covering a dynamic range from −7.5 dB to +8 dB. At the earpiece output,
the RX gain steps are multiplied by 2 due to the expander slope. The volume control
feature for the earpiece amplifier allows for compensation of gain tolerances from −15 dB
to +16 dB. Volume control is preferably done on the earpiece amplifier
(bits EARP_VOL[1:0]).
Rev. 01 — 8 February 2007
© NXP B.V. 2007. All rights reserved.
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