CS5522-ASZR Cirrus Logic Inc, CS5522-ASZR Datasheet - Page 25

• Manufacturer Part Number: CS5522-ASZR
• Description: IC ADC 24BIT 2CH 20-SSOP
• Manufacturer: Cirrus Logic Inc

Specifications of CS5522-ASZR

• Number Of Bits: 24
• Data Interface: Serial
• Number Of Converters: 1
• Power Dissipation (max): 14.8mW
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

1.2.4 Serial Port Interface
The CS5521/22/23/24/28’s serial interface consists
of four control lines: CS, SCLK, SDI, SDO.
Figure 10 illustrates the serial sequence necessary
to write to, or read from the serial port’s registers.
CS (Chip Select) is the control line which enables
access to the serial port. If the CS pin is tied low,
the port can function as a three-wire interface.
SDI (Serial Data In) is the data signal used to trans-
fer data to the converters.
SDO (Serial Data Out) is the data signal used to
transfer output data from the converters. The SDO
DS317F8
SCLK
SDO
* td = XIN/OWR clock cycles for each conversion except the
SDI
SCLK
SCLK
first conversion which will take XIN/OWR + 7 clock cycles
SDO
SDI
SDI
CS
CS
Command Time
8 SCLKs
Figure 10. Command and Data Word Timing
Command Time
Command Time
8 SCLKs
8 SCLKs
t *
d
8 SCLKs Clear SDO Flag
Write Cycle
MSB
MSB
Read Cycle
output will be held at high impedance any time CS
is at logic 1.
SCLK (Serial Clock) is the serial bit clock which
controls the shifting of data to or from the ADC’s
serial port. The CS pin must be held low (logic 0)
before SCLK transitions can be recognized by the
port logic. To accommodate opto-isolators SCLK
is designed with a Schmitt-trigger input to allow an
opto-isolator with slower rise and fall times to di-
rectly drive the pin. Additionally, SDO is capable
of sinking or sourcing up to 5 mA to directly drive
an opto-isolator LED. SDO will have less than a
400 mV loss in the drive voltage when sinking or
sourcing 5 mA.
Data Time 24 SCLKs
Data Time 24 SCLKs
MSB
Data Time
24 SCLKs
CS5521/22/23/24/28
Clock Cycles
XIN/OWR
LSB
LSB
LSB
25