Crystal CS5521-AP, Общее описание устройства

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CS5521 CS5523
DS317PP2 17
Configuration Register
* R indicates the bit value after the part is reset
D23(MSB) D22 D21 D20 D19 D18 D17 D16 D15 D14 D13 D12
NU NU CFS1 CFS0 NU MC LP RC NU DP2 DP1 DP0
D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
PSS PD PS/R NU RS RV OD OF NU NU NU NU
BIT NAME VALUE FUNCTION
D23-D22 Not Used, NU 00 R* Must always be logic 0.
D21-D20 Chop Frequency Select,
CFS1-CFS0 00
01
10
11
R 256 Hz Amplifier chop frequency.
4,096 Hz Amplifier chop frequency.
16,384 Hz Amplifier chop frequency.
1,024 Hz Amplifier chop frequency.
D19 Not Used, NU 0 R Must always be logic 0.
D18 Multiple Conversion, MC 0
1 R Perform single channel conversions. MC bit is ignored during calibrations.
Perform multiple conversions on logical channels in the channel-setup
register by issuing only one command with MSB = 1.
D17 Loop, LP 0
1 R Don’t loop. LP bit is ignored during calibrations.
The conversions on the single channel (MC = 0) or multiple channels (MC
= 1) are continuously performed.
D16 Read Convert, RC 0
1 R Don’t wait for user to finish reading data before starting new conversions.
The RC bit is used in conjunction with the LP bit when the LP bit is set to
logic 1. If LP = 0, the RC bit is ignored. If LP = 1, the ADC waits for user to
read data conversion(s) before converting again. The RC bit is ignored
during calibrations. Refer to Calibration Protocol for details.
D15 Not Used, NU 0 R Must always be logic 0.
D14-D12 Depth Pointer, DP2-DP0 000
.
.
111
R When writing or reading the CSRs, these bits (DP2-DP0) determine the
number of CSR’s to be accessed. They are also used to determine how
many logical channels are converted when MC=1 and a command byte
with its MSB = 1 is issued. Note that the CS5521 has two CSRs and the
CS5523 has four CSRs.
D11 Power Save Select, PSS 0
1 R Standby Mode (Oscillator active, allows quick power-up).
Sleep Mode (Oscillator inactive).
D10 Pump Disable, PD 0
1 R Charge Pump Enabled.
For PD = 1, the CPD pin goes to a Hi-Z output state.
D9 Power Save/Run, PS/R 0
1 R Run.
Power Save.
D8 Not Used, NU 0 R Must always be logic 0.
D7 Reset System, RS 0
1 R Normal Operation.
Activate a Reset cycle. To return to Normal Operation write bit to zero.
D6 Reset Valid, RV 0
1
R
No reset has occurred or bit has been cleared (read only).
Bit is set after a Valid Reset has occurred. (Cleared when read.)
D5 Oscillation Detect, OD 0
1 R Bit is clear when an oscillation condition has not occurred (read only).
Bit is set when an oscillatory condition is detected in the modulator.
D4 Overrange Flag, OF 0
1 R Bit is clear when an overrange condition has not occurred (read only).
Bit is set when input signal is more positive than the positive full scale,
more negative than zero (unipolar mode), or when the input is more neg-
ative then the negative full scale (bipolar mode).
D3-D0 Not Used, NU 0000 R Must always be logic 0.
Table 4. Configuration Register