RXC101 Datasheet, PDF (29/33 Pages) RF Monolithics, Inc – Multi-channel High data rate Programmable

Battery Detect Threshold and Clock Output Register [POR=C200h]
Bit Bit Bit Bit Bit Bit Bit Bit
Bit
Bit
Bit
Bit
Bit
Bit
Bit
Bit
15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
1
1
0
0
0
0
1
0 CLK2 CLK1 CLK0 LBD4 LBD3 LBD2 LBD1 LBD0
The Battery Detect Threshold and Clock Output Register configures the following:
• Low Battery Detect Threshold
• Output Clock frequency
The Low Battery Threshold is programmable from 2.2V to 5.3V using the following equation:
VT = (LBD[4..0] / 10) + 2.2 (V)
where LBD[4..0] is the decimal value 0 to 31.
Bit [15..8] - Command Code: These bits are the command code that is sent serially to the processor that
identifies the bits to be written to the Battery Detect Threshold and Clock Output Register.
Bit [7..5] – Clock Output Frequency: These bit set the output frequency of the on-board clock that may
be used to run an external host processor. See Table 15 below.
TABLE 15.
Output Clock Frequency (MHz)
1
1.25
1.66
2
2.5
3.33
5
10
CLK2
0
0
0
0
1
1
1
1
CLK1
0
0
1
1
0
0
1
1
CLK0
0
1
0
1
0
1
0
1
Bit [4..0] – Low Battery Detect Value: These bits set the decimal value as used in the equation above to
calculate the battery detect threshold voltage value. When the battery level falls 50mV below this value,
the LBD bit (5) in the status register is set indicating that the battery level is below the programmed
threshold. This is useful in monitoring discharge sensitive batteries such as Lithium cells.
The Low Battery Detect can be enabled by setting the LBDEN bit (2) of the Power Management Register
and disabled by clearing the bit.
The Clock Output can be enabled by setting the CLKEN bit (0) of the Power Management Register and
disabled by clearing the bit.
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