AD5933YRSZ Analog Devices Inc, AD5933YRSZ Datasheet - Page 33

• Manufacturer Part Number: AD5933YRSZ
• Description: IC NTWK ANALYZER 12B 1MSP 16SSOP
• Manufacturer: Analog Devices Inc

Specifications of AD5933YRSZ

• Resolution (bits): 12 b
• Master Fclk: 16.776MHz
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 16-SSOP
• Supply Voltage Range: 2.7V To 5.5V
• Operating Temperature Range: -40°C To +125°C
• Digital Ic Case Style: SSOP
• No. Of Pins: 16
• Frequency Max: 0.1MHz
• Termination Type: SMD
• Pin Count: 16
• Screening Level: Automotive
• Package Type: SSOP
• Filter Terminals: SMD
• Rohs Compliant: Yes
• Communication Function: Network Analyzer
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: EVAL-AD5933EBZ - BOARD EVALUATION FOR AD5933
• Tuning Word Width (bits): -
• Lead Free Status / Rohs Status: Compliant
• Other names: AD5933BRSZ; Q2204656A

BIOMEDICAL: NONINVASIVE BLOOD IMPEDANCE
MEASUREMENT
When a known strain of a virus is added to a blood sample
that already contains a virus, a chemical reaction takes place
whereby the impedance of the blood under certain conditions
changes. By characterizing this effect across different frequencies,
it is possible to detect a specific strain of virus. For example, a
strain of the disease exhibits a certain characteristic impedance
at one frequency but not at another; therefore, the requirement
is to sweep different frequencies to check for different viruses.
The AD5933, with its 27-bit phase accumulator, allows for
subhertz frequency tuning.
the blood sample via a probe. The response signal is analyzed,
and the effective impedance of the blood is tabulated. The
AD5933 is ideal for this application because it allows the user
to tune to the specific frequency required for each test.
The AD5933 can be used to inject a stimulus signal through
PROBE
Figure 42. Measuring a Blood Sample for a Strain of Virus
0.1µF
7V
10µF
RFB
1
2
3
4
5
6
7
8
2
(Not to Scale)
AD5933
TOP VIEW
ADR43x
4
16
15
14
13
12
11
10
9
6
(Not to Scale)
ADuC702x
TOP VIEW
Rev. C | Page 33 of 44
SENSOR/COMPLEX IMPEDANCE MEASUREMENT
The operational principle of a capacitive proximity sensor is
based on the change of a capacitance in an RLC resonant
circuit. This leads to changes in the resonant frequency of the
RLC circuit, which can be evaluated as shown Figure 43.
It is first required to tune the RLC circuit to the area of
resonance. At the resonant frequency, the impedance of the
RLC circuit is at a maximum. Therefore, a programmable
frequency sweep and tuning capability is required, which is
provided by the AD5933.
An example of the use of this type of sensor is for a train
proximity measurement system. The magnetic fields of the
train approaching on the track change the resonant frequency
to an extent that can be characterized. This information can be
sent back to a mainframe system to show the train location
on the network.
Another application for the AD5933 is in parked vehicle detec-
tion. The AD5933 is placed in an embedded unit connected to
a coil of wire underneath the parking location. The AD5933
outputs a single frequency within the 80 kHz to 100 kHz
frequency range, depending upon the wire composition. The
wire can be modeled as a resonant circuit. The coil is calibrated
with a known impedance value and at a known frequency. The
impedance of the loop is monitored constantly. If a car is parked
over the coil, the impedance of the coil changes and the
AD5933 detects the presence of the car.
Figure 43. Detecting a Change in Resonant Frequency
FREQUENCY
RESONANT
FREQUENCY (Hz)
F
O
TO APPROACHING
RESONANCE DUE
CHANGE IN
OBJECT
AD5933