CS5501-BS Cirrus Logic Inc, CS5501-BS Datasheet - Page 52

• Manufacturer Part Number: CS5501-BS
• Description: A/D Converter (A-D) IC
• Manufacturer: Cirrus Logic Inc

Specifications of CS5501-BS

• Peak Reflow Compatible (260 C): No
• No. Of Bits: 16 Bit
• Leaded Process Compatible: No
• Mounting Type: Surface Mount
• Interface Type: Serial
• Package / Case: 20-SOIC
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Oscilloscope Monitoring of SDATA
The output data from either the CS5501 or the
CS5503 can be observed on a dual trace oscillo-
scope with the following hook-up. Set the
evaluation board to operate in the SSC mode.
Connect scope probes to TP9 (SCLK) and TP10
(SDATA). Use a third probe connected to TP8
(DRDY) to provide the external trigger input to
the scope (use falling edge of DRDY to trigger).
With proper horizontal sweep, the SDATA output
bits from the A/D converter can be observed.
Note that if the input voltage to the CS5501 is
adjusted to a mid-code value, the converter will
remain stable on the same output code. This illus-
trates the low noise level of the CS5501. The
CS5503 will exhibit a few LSB’s of noise in its
observed output in agreement with its noise speci-
fications.
52
Evaluation Board Component Layout and
Design Considerations
Figure 7 is a reproduction of the silkscreen com-
ponent placement of the PC board.
The evaluation board includes design features to
insure proper performance from the A/D con-
verter chip. Separate analog and digital ground
planes have been used on the board to insure
good noise immunity to digital system noise.
Decoupling networks (R6, C7, and R7, C9 in Fig-
ure 6) have been used to eliminate the possibility
of noise on the power supplies on the digital sec-
tion from affecting the analog part of the A/D
converter chip.
The RC network (R10, C16 and C19) on the
output of the LT1019-2.5 reference may not be
needed in all applications. It has been included to
insure the best noise performance from the refer-
ence .
CDB5501/CDB5503
DS31DB3