Datasheet

Data Sheet AD5933
Rev. E | Page 23 of 40
REGISTER MAP
Table 8.
Register Name Register Data Function
0x80 Control D15 to D8 Read/write
0x81
D7 to D0
Read/write
0x82 Start frequency D23 to D16 Read/write
0x83 D15 to D8 Read/write
0x84 D7 to D0 Read/write
0x85 Frequency increment D23 to D16 Read/write
0x86 D15 to D8 Read/write
0x87
D7 to D0
Read/write
0x88 Number of increments D15 to D8 Read/write
0x89 D7 to D0 Read/write
0x8A Number of settling time cycles D15 to D8 Read/write
0x8B D7 to D0 Read/write
0x8F Status D7 to D0 Read only
0x92 Temperature data D15 to D8 Read only
0x93 D7 to D0 Read only
0x94
Real data
D15 to D8
Read only
0x95 D7 to D0 Read only
0x96 Imaginary data D15 to D8 Read only
0x97 D7 to D0 Read only
CONTROL REGISTER (REGISTER ADDRESS 0x80,
REGISTER ADDRESS 0x81)
The AD5933 has a 16-bit control register (Register Address 0x80
and Register Address 0x81) that sets the AD5933 control
modes. The default value of the control register upon reset is
as follows: D15 to D0 reset to 0xA000 upon power-up.
The four MSBs of the control register are decoded to provide
control functions, such as performing a frequency sweep,
powering down the part, and controlling various other
functions defined in the control register map.
The user may choose to write only to Register Address 0x80 and
not to alter the contents of Register Address 0x81. Note that the
control register should not be written to as part of a block write
command. The control register also allows the user to program
the excitation voltage and set the system clock. A reset command
to the control register does not reset any programmed values
associated with the sweep (that is, start frequency, number of
increments, frequency increment). After a reset command, an
initialize with start frequency command must be issued to the
control register to restart the frequency sweep sequence (see
Figure 28).
Table 9. Control Register Map (D15 to D12)
D15 D14 D13 D12 Function
0 0 0 0 No operation
0 0 0 1 Initialize with start frequency
0 0 1 0 Start frequency sweep
0 0 1 1 Increment frequency
0 1 0 0 Repeat frequency
1 0 0 0 No operation
1 0 0 1 Measure temperature
1
0
1
0
Power-down mode
1 0 1 1 Standby mode
1 1 0 0 No operation
1 1 0 1 No operation
Table 10. Control Register Map (D10 to D9)
D10 D9 Range No. Output Voltage Range
0 0 1 2.0 V p-p typical
0 1 4 200 mV p-p typical
1
0
3
400 mV p-p typical
1 1 2 1.0 V p-p typical