SA58646 Datasheet, PDF (21/42 Pages) NXP Semiconductors – UHF 900 MHz transceiver IC

NXP Semiconductors
SA58646
UHF 900 MHz transceiver IC
8.6 Data register 5
Table 15. Data register 5 (address 101h) bit description
Legend: * reset value.
Bit
Symbol
Value Description
15
REG
Internal voltage regulator
0
disable and tied to supply voltage V_CC (in Inactive mode)
1* enable
14
MODE[1:0]
Active mode selection. See details in Table 4 “Activated
blocks”.
00* Inactive mode
01 Inactive mode
10 RX mode
11 Active mode
13
XTAL_H
Crystal high current. In Inactive mode, the crystal
oscillator is a major contributor to the full current
consumption.
0
save current operation yields a full current consumption in
Inactive mode at 230 µA; see details in Section 7.1.3
“Control bits in power saving modes”
1* crystal oscillator current is increased by 100 µA
11 to 7 CAR_DET_LEV[4:0]
Carrier detection threshold programming. When bit
BAT_DET = 0, the carrier detector is enabled and the
signal Carrier detection is routed to the output pin
CDLBD. If RSSI is above the programmed RSSI level, pin
CDLBD = LOW; if not then pin CDLBD = HIGH. The
carrier detector gives an indication if a carrier signal is
present on the selected channel. The nominal value and
tolerance of the carrier detection threshold is given in the
carrier detector specification. If a different carrier
detection threshold value is desired, it can be
programmed through the microcontroller interface. To
scale the carrier detection range, connect an external
resistor from pin RSSI to ground. The value 1 0011
corresponds to RSSI = 0.86 V (typical DC value).
0
For values, see Table 16
0000*
6 to 4 L_BAT_DET[2:0]
000*
Low battery detector voltage. When bit BAT_DET = 1,
the low battery detector is enabled and the signal BDout
is routed to the output pin CDLBD. If the supply voltage is
below the programmed level, pin CDLBD = LOW and if
not, pin CDLBD = V_CC.
3.5 V
001 3.4 V
010 3.3 V
011 3.2 V
100 3.1 V
101 3.0 V
110* 2.9 V
111 2.8 V
SA58646_1
Product data sheet
Rev. 01 — 8 February 2007
© NXP B.V. 2007. All rights reserved.
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