Chipcon CC1000, Manual

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CC1000
SWRS048A Page 41 of 55
CURRENT Register (09h)
REGISTER NAME Default
value
Active Description
CURRENT[7:4] VCO_CURRENT[3:0] 1100 - Control of current in VCO core for TX and RX
0000 : 150
µ
A
0001 : 250
µ
A
0010 : 350
µ
A
0011 : 450
µ
A
0100 : 950
µ
A, use for RX, f= 400 – 500 MHz
0101 : 1050
µ
A
0110 : 1150
µ
A
0111 : 1250
µ
A
1000 : 1450
µ
A, use for RX, f<400 MHz and f>500
MHz; and TX, f= 400 – 500 MHz
1001 : 1550
µ
A, use for TX, f<400 MHz
1010 : 1650
µ
A
1011 : 1750
µ
A
1100 : 2250
µ
A
1101 : 2350
µ
A
1110 : 2450
µ
A
1111 : 2550
µ
A, use for TX, f>500 MHz
CURRENT[3:2] LO_DRIVE[1:0] 10 Control of current in VCO buffer for LO drive
00 : 0.5mA, use for TX
01 : 1.0mA , use for RX, f<500 MHz*
10 : 1.5mA,
11 : 2.0mA, use for RX, f>500 MHz *
* LO_DRIVE can be reduced to save current in
RX mode. See
Table 10
for details
CURRENT[1:0] PA_DRIVE[1:0] 10 Control of current in VCO buffer for PA
00 : 1mA, use for RX
01 : 2mA, use for TX, f<500 MHz
10 : 3mA
11 : 4mA, use for TX, f>500 MHz
FRONT_END Register (0Ah)
REGISTER NAME Default
value
Active Description
FRONT_END[7:6] - 00 - Not used
FRONT_END[5] BUF_CURRENT 0 - Control of current in the LNA_FOLLOWER
0 : 520uA, use for f<500 MHz
1 : 690uA, use for f>500 MHz *
*BUF_CURRENT can be reduced to save
current in RX mode. See
Table 10
for details.
FRONT_END[4:3] LNA_CURRENT
[1:0]
01 - Control of current in LNA
00 : 0.8mA, use for f<500 MHz *
01 : 1.4mA
10 : 1.8mA, use for f>500 MHz *
11 : 2.2mA
*LNA_CURRENT can be reduced to save
current in RX mode. See
Table 10
for details.
FRONT_END[2:1] IF_RSSI[1:0] 00 - Control of IF_RSSI pin
00 : Internal IF and demodulator, RSSI inactive
01 : RSSI active, RSSI/IF is analog RSSI output
10 : External IF and demodulator, RSSI/IF is
mixer output. Internal IF in power down mode.
11 : Not used
FRONT_END[0] XOSC_BYPASS 0 - 0 : Internal XOSC enabled
1 : Power-Down of XOSC, external CLK used