AD7853 Analog Devices, AD7853 Datasheet - Page 11

• Manufacturer Part Number: AD7853
• Description: 3 V to 5 V Single Supply, 200 kSPS, 12-Bit, Serial Sampling ADC
• Manufacturer: Analog Devices

Specifications of AD7853

• Resolution (bits): 12bit
• # Chan: 1
• Sample Rate: 200kSPS
• Interface: Ser,SPI
• Analog Input Type: Diff-Uni,SE-Uni
• Ain Range: (Vref) p-p,Uni (Vref)
• Adc Architecture: SAR
• Pkg Type: DIP,SOIC

REV. B
STATUS REGISTER
The arrangement of the status register is shown below. The status register is a read-only register and contains 16 bits of data. The
status register is selected by first writing to the control register and putting two 1s in RDSLT1 and RDSLT0. The function of the
bits in the status register are described below. The power-up status of all bits is 0.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Bit
Mnemonic
ZERO
BUSY
ZERO
ZERO
ZERO
ZERO
PMGT1
PMGT0
RDSLT1
RDSLT0
2/3 MODE
X
CALMD
CALSLT1
CALSLT0
STCAL
MSB
RDSLT1
ZERO
Comment
This bit is always 0.
Conversion/Calibration Busy Bit. When this bit is 1, it indicates that there is a conversion or calibration in
progress. When this bit is 0, no conversion or calibration is in progress.
These four bits are always 0.
Power Management Bits. These bits, along with the SLEEP pin, will indicate whether or not the part is in a
power-down mode. See Table VI in Power-Down Section for description.
Both of these bits are always 1, indicating it is the status register that is being read. See Table II.
Interface Mode Select Bit. With this bit at 0, the device is in Interface Mode 2. With this bit at 1, the device
is in Interface Mode 1. This bit is reset to 0 after every read cycle.
Don’t care bit.
Calibration Mode Bit. A 0 in this bit indicates a self-calibration is selected; a 1 in this bit indicates a system
calibration is selected (see Table III).
Calibration Selection Bits and Start Calibration Bit. The STCAL bit is read as a 1 if a calibration is in
progress and as a 0 if no calibration is in progress. The CALSLT1 and CALSLT0 bits indicate
which of the calibration registers are addressed for reading and writing (see section on the Calibration
Registers for more details).
RDSLT0
BUSY
Figure 6. Flowchart for Reading the Status Register
2/3 MODE
ZERO
Status Register Bit Function Descriptions
WRITE TO CONTROL REGISTER
ZERO
SETTING RDSLT0 = RDSLT1 = 1
READ STATUS REGISTER
X
–11–
START
CALMD
ZERO
CALSLT1
ZERO
CALSLT0
PMGT1
AD7853/AD7853L
PMGT0
STCAL
LSB