EVAL-CN0335-PMDZ [ADI]

PMOD BOARD 12BIT 300KSPS ADC;
EVAL-CN0335-PMDZ
型号: EVAL-CN0335-PMDZ
厂家: ADI    ADI
描述:

PMOD BOARD 12BIT 300KSPS ADC

文件: 总8页 (文件大小:210K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
Circuit Note  
CN-0335  
Devices Connected/Referenced  
Precision, Low Noise, Dual CMOS, Rail-  
to-Rail Input/Output Op Amp  
AD8606  
Circuits from the Lab® reference designs are engineered and  
tested for quick and easy system integration to help solve today’s  
analog, mixed-signal, and RF design challenges. For more  
information and/or support, visit http://www.analog.com/CN0335.  
AD7091R  
ADuM5401  
1 MSPS, Ultralow Power, 12-Bit ADC  
Quad-Channel, 2.5 kV Isolators with  
Integrated DC-to-DC Converter  
12-Bit, 300 kSPS, Single-Supply, Fully Isolated, Data Acquisition System  
for 10 V Inputs  
The system processes 10 V input signals using a single 3.3 V  
supply. The total error after room temperature calibration is less  
than 0.1% FSR over a 10°C temperature change, making it  
ideal for a wide variety of industrial measurements.  
EVALUATION AND DESIGN SUPPORT  
Circuit Evaluation Boards  
CN0335 Circuit Evaluation Board (EVAL-CN0335-PMDZ)  
SDP/PMD Interposer Board (SDP-PMD-IB1Z)  
System Demonstration Platform (EVAL-SDP-CB1Z)  
Design and Integration Files  
The small footprint of the circuit makes this combination an  
industry-leading solution for data acquisition systems where the  
accuracy, speed, cost, and size play a critical role. Both data and  
power are isolated, thereby making the circuit robust to high  
voltages and also ground-loop interference often encountered  
in harsh industrial environments.  
Schematics, Layout Files, Bill of Materials  
CIRCUIT FUNCTION AND BENEFITS  
The circuit shown in Figure 1 is a completely isolated 12-bit,  
300 kSPS data acquisition system utilizing only three active devices.  
U1B  
1/2 AD8606  
C11  
DNP  
U2  
VREF  
ADuM5401  
(C-GRADE)  
R1  
52.3kΩ  
R2  
12kΩ  
+3.3V  
+3.3V  
V
V
+3.3V_IN  
GND  
ISO  
DD1  
GND  
GND1  
TP1  
ISO  
+3.3V  
+0.1V TO +2.4V  
REF  
V
V
V
SS  
CS  
SCLK  
OUT  
U3  
DD  
OA  
IA  
U1A  
1/2 AD8606  
GND_ISO  
R3  
51Ω  
V
V
SCK  
OB  
IB  
V
V
V
CONVST  
MISO  
CONVST  
SDO  
IN  
OC  
IC  
AD7091R  
C9  
4.7nF  
V
V
ID  
OD  
+3.3V  
V
RC  
OUT  
V
GND REGCAP  
SEL  
GND_ISO  
DRIVE  
INPUT  
GND  
GND1  
GND  
ISO  
R4  
R5  
–10V TO +10V  
GND_ISO  
C8  
1µF  
52.3kΩ  
12kΩ  
ISOLATION  
PMOD CON  
12-PIN  
J1  
VREF  
2.5V  
1
2
GND_ISO  
C10  
DNP  
R6  
10kΩ  
GND_ISO  
CON  
J2  
GND_ISO  
GND_ISO  
Figure 1. 10 V Single Supply Data Acquisition System with Isolation (All Connections and Decoupling Not Shown)  
Rev. A  
Circuitsfromthe Lab®reference designsfrom Analog Deviceshave been designedandbuilt by Analog  
Devices engineers. Standard engineering practices have been employed in the design and  
construction of each circuit, and their function and performance have been tested and verified in a lab  
environment at room temperature. However, you are solely responsible for testing the circuit and  
determining its suitability and applicability for your use and application. Accordingly, in no event shall  
Analog Devices be liable for direct, indirect, special, incidental, consequential or punitive damages due  
toanycausewhatsoeverconnectedtotheuseofanyCircuitsfromtheLabcircuits. (Continuedonlastpage)  
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.  
Tel: 781.329.4700  
Fax: 781.461.3113  
www.analog.com  
©2014 Analog Devices, Inc. All rights reserved.  
 
CN-0335  
Circuit Note  
Galvanic isolation is provided by the ADuM5401 (C-Grade)  
quad channel digital isolator. In addition to the isolated output  
data, the ADuM5401 also provides isolated 3.3 V for the circuit.  
The ADuM5401 is not required for normal circuit operation  
unless isolation is needed. The ADuM5401 quad-channel,  
2.5 kV isolators with integrated dc-to-dc converter, is available  
in a small 16-lead SOIC. Power dissipation of the ADuM5401  
with a 7 MHz clock is approximately 140 mW.  
CIRCUIT DESCRIPTION  
The circuit consists of an input signal conditioning stage, an  
ADC stage, and an output isolation stage. The 10 V input  
signal is level shifted and attenuated by the U1A op amp that is  
one-half of the dual AD8606. The output of the op amp is 0.1 V  
to 2.4 V, which matches the input range of the ADC (0 V to  
2.5 V) with 100 mV headroom to maintain linearity. The  
buffered voltage reference (VREF =2.5 V) from the ADC is used  
to generate the required offset. Resistor values can be modified  
to accommodate other popular input ranges as described later  
in this circuit note.  
The AD7091R requires a 50 MHz serial clock (SCLK) to achieve  
a 1 MSPS sampling rate. However, the ADuM5401 (C-grade)  
isolator has a maximum data rate of 25 Mbps that corresponds  
to a maximum serial clock frequency of 12.5 MHz. In addition,  
the SPI port requires that the trailing edge of the SCLK clock  
the output data into the processor, therefore the total round-trip  
propagation delay through the ADuM5401 (120 ns maximum)  
limits the upper clock frequency to 1/120 ns = 8.3 MHz.  
The circuit design allows single supply operation. The minimum  
output voltage specification of the AD8606 is 50 mV for a 2.7 V  
power supply and 290 mV for 5 V power supply with 10 mA  
load current, over the temperature range of −40°C to +125°C. A  
minimum output voltage of 45 mV to 60 mV is a conservative  
estimate for a 3.3 V power supply, a load current less than  
1 mA, and a narrower temperature range.  
Even though the AD7091R is a 12-bit ADC, the serial data is  
formatted into a 16-bit word to be compatible with the processor  
serial port requirements. The sampling period, TS, therefore  
consists of the AD7091R 650 ns conversion time plus 58 ns  
(extra time required from data sheet, t1 delay + tQUIET delay) plus  
16 clock cycles for the SPI interface data transfer.  
Considering the tolerances of the parts, the minimum output  
voltage (low limit of the range) is set to 100 mV to allow a safety  
margin. The upper limit of the output range is set to 2.4 V in  
order to give 100 mV headroom for the positive swing at the  
ADC input. Therefore, the nominal output voltage range of the  
input op amp is 0.1 V to 2.4 V.  
TS = 650 ns + 58 ns + 16 × 120 ns = 2628 ns  
fS = 1/TS = 1/2628 ns = 380 kSPS  
The second half of the AD8606 (U1B) is used to buffer the  
internal 2.5 V voltage reference of the AD7091R (U3) ADC.  
In order to provide a safety margin, a maximum SCLK of  
7 MHz and a maximum sampling rate of 300 kSPS is  
recommended. The digital SPI interface can be connected to the  
microprocessor evaluation board using the 12-pin Pmod-  
compatible connector (Digilent Pmod Specifications).  
The AD8606 is chosen for this application because of its low offset  
voltage (65 μV maximum), low bias current (1 pA maximum)  
and low noise (12 nV/√Hz maximum). Power dissipation is  
only 9.2 mW on a 3.3 V supply.  
Circuit Design  
The circuit shown in Figure 2 attenuates and level shifts the −10 V  
to +10 V input signal to the ADC input range of 0.1 V to 2.4 V.  
A single-pole RC filter (R3/C9) follows the op amp output stage  
to reduce the out-of-band noise. The cutoff frequency of the RC  
filter is set to 664 kHz. An optional second order filter (R4, C10,  
andR1,R2, C11) can be added to reduce the filter cutoff frequency  
even further in case of low frequency industrial noise. In such  
case, the sampling rate of the AD7091R can be reduced because  
of the lower signal bandwidth.  
R1  
52.3kΩ  
R2  
12kΩ  
+3.3V  
U1A  
1/2 AD8606  
OUTPUT  
+0.1V TO +2.4V  
GND_ISO  
The AD7091R 12-bit 1 MSPS SAR ADC is chosen because of its  
ultralow power 349 μA at 3.3 V (1.2 mW) which is significantly  
lower than any competitive ADC currently available in the market.  
The AD7091R also contains an internal 2.5 V reference with  
4.5 ppm/oC typical drift. The input bandwidth is 7.5 MHz,  
and the high speed serial interface is SPI compatible. The  
AD7091R is available in a small footprint 10-lead MSOP.  
GND_ISO  
INPUT  
R4  
52.3kΩ  
R5  
12kΩ  
–10V TO +10V  
GND_ISO  
VREF  
2.5V  
1
R6  
2
10kΩ  
GND_ISO  
GND_ISO  
Figure 2. Input Voltage Signal Conditioning Circuit  
The total power dissipation of the circuit (excluding the  
ADuM5401 isolator) is approximately 10.4 mW when  
operating on a 3.3 V supply.  
Rev. A | Page 2 of 8  
 
 
Circuit Note  
CN-0335  
In the actual circuit the nearest available standard resistor  
values were chosen for R4 and R5. The values selected were R4  
= 52.3 kΩ and R5 = 12 kΩ. Note that R1 = R4 and R2 = R5.  
The transfer function is obtained from the superposition principle:  
R5 R6  
R4 R6  
R2  
R2  
VOUT = V IN  
1+  
+V REF  
1+  
=
If these values are chosen carefully, the overall error due to  
substituting standard value resistors can be made less than a few  
percent. However, use Equation 1 to recalculate the U1A op  
amp output for 10 V inputs to ensure that the required  
headroom is preserved.  
R4 + R5 R6   
R1   
R5 + R4 R6   
R1   
R
R0  
= V IN  
k +V REF  
k = V IN GAIN + OFFSET  
R4 + R  
R5 + R0  
(1)  
The absolute accuracy in this type of circuit is primarily  
determined by the resistors, and therefore gain and offset  
calibration is required to remove the error due to standard value  
substitution and resistor tolerances.  
where:  
R = R5 R6 =  
R5R6  
R4R6  
,
(2)  
(3)  
R0 = R4 R6 =  
R5 + R6  
R4 + R6  
Calculation of Resistor Values for Different Input Ranges  
R2  
and  
k = 1+  
For input ranges other than 10 V complete the following  
calculation steps.  
R1   
Calculation of the Gain, Output Offset, and the Resistor  
Values  
Define the input span, the output span, and the offset:  
(11)  
(12)  
VIN =VIN _ MAX VIN _ MIN  
VOUT =VIOUT _ MAX VOUT _ MIN  
VOUT  
For input voltage range 10 V, the calculations are as follows.  
The gain of the circuit is:  
VOUT  
V IN  
2.4 V 0.1 V  
2.3 V  
(4)  
(5)  
(13)  
Offset =  
+VOUT _ MIN  
GAIN =  
=
=
= 0.115  
2
+10V (10 V) 20 V  
Calculate the gain:  
VOUT  
and according to the transfer function:  
(14)  
GAIN =  
R5 R6  
R2  
R
VIN  
GAIN =  
1+  
=
k
R4 + R5 R6   
R1 R4 + R  
Calculate the offset:  
The output offset of the circuit is:  
VOUT  
2
(15)  
(16)  
Offset =  
+VOUT _ MIN  
2.4 V 0.1 V  
OFFSET = VOUT (V IN = 0 V) = 0.1 V +  
= 1.25 V  
Choose the value for the parameter k:  
2
(6)  
R2  
k = 1+  
and according to the transfer function:  
R1   
R4 R6  
R2  
R0  
Calculate the ratio R4/R, using:  
OFFSET = V REF  
1+  
= V REF  
k
R5 + R4 R6   
R1   
R5 + R0  
R
(17)  
(18)  
GAIN =  
k
(7)  
R4 + R  
From Equation 4, for k =1.23 (this value can vary, depending on  
the value of the standard value resistors R1 and R2), the ratio  
R4/R can be calculated:  
Calculate the ratio R5/R0, using:  
R0  
Offset = V REF  
k
R5 + R0  
(8)  
R4 = 9.696 R  
Replace R and R0 in Equation 17 and Equation 18 with the  
values defined in Equation 2, and solve both equations find the  
ratio R4/R6.  
From Equation 7, for VREF = 2.5V and k =1.23 the ratio R5/R0  
can be calculated:  
(9)  
R5 =1.46 R0  
Choose a value for the resistor R6. Calculate R4 using the ratio of  
R4/R6. Knowing the values for R4 and R6, calculate R5 using  
Equation 2 and the R4/R6 ratio. Calculate R2 and R1 using  
Equation 16. It is reasonable to choose R1 = R4 and calculate R2.  
Using Equation 2 for the resistors R and R0, and the ratios in  
Equation 8 and Equation 9, the ratio R4/R6 can be calculated:  
(10)  
R4 = 5.346 R6  
From Equation 8, Equation 9, and Equation 10, the resistors R4,  
R5, and R6 can be calculated. For example choosing R6 = 10 kΩ  
leads to R4 = 53.46 kΩ, and R5 =12.3 kΩ.  
Rev. A | Page 3 of 8  
CN-0335  
Circuit Note  
Effect of Resistor Temperature Coefficients on Overall  
Error  
Test Data Before and After Two-Point Calibration  
To perform the two-point calibration, −10 V is first applied to  
the input, and the ADC output code is recorded as Code_1.  
Then +10 V is applied to the input, and the ADC output code is  
recorded as Code_2. The gain factor is calculated by  
Equation 1 shows that the output voltage is a function of five  
resistors: R1, R2, R4, R5, and R6. The sensitivity of the full-scale  
output voltage at TP1 to small changes in each of the five  
resistors was calculated using a simulation program. The input  
voltage to the circuit was +10 V. The individual sensitivities  
20 V  
GF =  
Code_2 Code_1  
calculated were SR1 = 0.19, SR2 = 0.19, SR4 = 0.39, SR5 = 0.11, SR6  
=
0.50. Assuming the individual temperature coefficients combine  
in a root-sum-square (rss) manner, then the overall full-scale  
drift using 100 ppm/°C resistors is approximately:  
The input voltage can now be calculated corresponding to any  
output code, Code_x, using the equation:  
.
V IN = −10 V + GF (Code_x Code_1)  
Full scale drift =  
The error before calibration is obtained by comparing the ideal  
transfer function calculated using the nominal values of the  
components, and real circuit transfer function without  
calibration. The tested circuits have been built with resistors  
having 1% tolerance. The test results do not include  
temperature changes.  
2
=100 ppm/°C √(SR12 + SR22 + SR42 + SR52 + SR6  
)
=100 ppm/°C √(0.192 + 0.192 + 0.392 + 0.112 + 0.502)  
= 69 ppm/°C  
The full scale drift of 69 ppm/°C corresponds to 0.0069%  
FSR/°C. Using 25 ppm/°C resistors reduces the drift error to  
0.25 × 69 ppm/°C = 17 ppm/°C, or 0.0017% FSR/°C.  
The graph in Figure 3 shows test results for percent error (FSR)  
before and after calibration at ambient temperature. As it is shown,  
the maximum error before calibration is about 0.23% FSR.  
After calibration, the error decreases to 0.03% FSR, which  
approximately corresponds to 1 LSB error of the ADC.  
0.25  
Effect of Active Component Temperature Coefficients on  
Overall Error  
The dc offsets of the AD8606 op amps and the AD7091R ADC  
are eliminated by the calibration procedure.  
The offset drift of the ADC AD7091R internal reference is  
4.5 ppm/°C typical and 25 ppm/°C maximum.  
0.20  
0.15  
0.10  
0.05  
0
ERROR BEFORE CALIBRATION  
The offset drift of the AD8606 op amp is 1μV/°C typical and  
4.5μV/°C maximum.  
The error due to the U1A input AD8606 is referenced to the  
2.3 V output range and is therefore 2 ppm/°C. The error due to  
the U1B reference buffer is referenced to 2.5 V and is also  
approximately 2 ppm/°C.  
ERROR AFTER CALIBRATION  
The total drift error is summarized in Table 1. These errors do  
not include the 1 LSB integral nonlinearity error of the AD7091R.  
–0.05  
Note that resistor drift is the largest contributor to total drift if  
50 ppm/°C or 100 ppm/°C resistors are used, and the drift due  
to active components can be neglected.  
–10  
–5  
0
5
10  
INPUT VOLTAGE (V)  
Figure 3. Circuit Test Error Before and After Room Temperature Calibration  
PCB Layout Considerations  
Table 1. Error Due to Temperature Drift  
In any circuit where accuracy is crucial, it is important to consider  
the power supply and ground return layout on the board. The  
PCB should isolate the digital and analog sections as much as  
possible. The PCB for this system was constructed in a simple  
2-layer stack up, but a 4-layer stack up gives better EMS. See the  
MT-031 Tutorial for more information on layout and grounding  
and the MT-101 Tutorial for information on decoupling  
techniques. Decouple the power supply to AD8606 with 10 μF  
and 0.1 μF capacitors to properly suppress noise and reduce ripple.  
Place the capacitors as close to the device as possible with the  
0.1 μF capacitor having a low ESR value. Ceramic capacitors are  
advised for all high frequency decoupling. Power supply lines  
should have as large trace width as possible to provide a low  
impedance path and to reduce glitch effects on the supply line.  
Error Source  
Total Error  
Resistors (1%, 100 ppm/°C)  
AD7091R (∆VVREF/∆T = 25 ppm/°C)  
AD8606, U1A (∆VOS/∆T= 4.5 μV/°C), 2  
ppm/°C, Referenced to 2.3 V  
AD8606, U1B (∆VOS/∆T= 4.5 μV/°C), 2  
ppm/°C, Referenced to 2.5 V  
Total FSR Error Temperature Coefficient  
(100 ppm/°C Resistors)  
Total % FSR Error for ∆T= 10°C (100 ppm/°C  
Resistors)  
Total % FSR Error for ∆T= 10°C (25 ppm/°C  
Resistors)  
0.0069% FSR/°C  
0.0025% FSR/°C  
0.0002% FSR/°C  
0.0002% FSR/°C  
0.0098% FSR/°C  
0.098% FSR  
0.046% FSR  
Rev. A | Page 4 of 8  
 
 
Circuit Note  
CN-0335  
The ADuM5401 isoPower integrated dc-to-dc converter requires  
power supply bypassing at the input and output supply pins. Note  
that low ESR bypass capacitors are required between Pin 1 and  
Pin 2 and between Pin 15 and Pin 16, as close to the chip pads  
as possible. To suppress noise and reduce ripple, a parallel com-  
bination of at least two capacitors is required. The recommended  
capacitor values are 0.1 μF and 10 μF for VDD1 and VISO. The  
smaller capacitor must have a low ESR, for example, use of a  
ceramic capacitor is advised. The total lead length between the  
ends of the low ESR capacitor and the input power supply pin  
must not exceed 2 mm. Installing the bypass capacitor with  
traces more than 2 mm in length may result in data corruption.  
Consider bypassing between Pin 1 and Pin 8 and between Pin 9  
and Pin 16, unless both common ground pins are connected  
together close to the package. For more information, see the  
ADuM5401 datasheet.  
COMMON VARIATIONS  
The circuit is proven to work with good stability and accuracy  
with component values shown. Other precision op-amps and  
other ADCs can be used in this configuration to convert 10V  
input voltage range to digital output and for other various  
applications for this circuit.  
The circuit in Figure 1 can be designed for other than 10 V  
input voltage ranges, following the equations given in the  
Circuit Design section. Table 2 shows the resistor calculations  
for some standard voltage ranges.  
Table 2. Component Values for Standard Voltage Ranges  
Range (V)  
k
1.2  
2
R4 (kΩ)  
R5 (kΩ)  
18.8  
37  
R6 (kΩ)  
5
2
1
40.87  
32.174  
40.87  
20  
20  
20  
4
94  
A complete documentation package including schematics,  
board layout, and bill of materials (BOM) can be found at  
www.analog.com/CN0335-DesignSupport.  
0 to 1  
0 to 2  
0 to 2.5  
0 to 5  
0 to 10  
0 to 24  
4
2
2
2
1
1
14.435  
14.087  
22.609  
65.217  
63.478  
90.174  
830  
405  
520  
750  
365  
216  
20  
20  
20  
20  
20  
10  
High Voltage Capability  
This PCB is designed in adherence with 2500 V basic insulation  
practices. High voltage testing beyond 2500 V is not recommended.  
Take appropriate care when using this evaluation board at high  
voltages, and do not rely on the PCB for safety functions because it  
has not been high potential tested (also known as hipot tested  
or dielectric withstanding voltage tested) or certified for safety.  
In the cases, when the lower range is zero and the upper range is  
greater than the reference voltage the conversion does not need  
gain (k = 1), and the circuit can be simplified. An example is  
shown in Figure 4 for the input range 0 V to 10 V.  
U1B  
1/2 AD8606  
U2  
VREF  
ADuM5401  
(C-GRADE)  
+3.3V  
+3.3V  
V
V
+3.3V_IN  
GND  
ISO  
DD1  
GND  
GND1  
TP1  
0.1V TO 2.4V  
ISO  
+3.3V  
REF  
V
V
V
SS  
CS  
SCLK  
OUT  
U3  
DD  
OA  
IA  
U1A  
1/2 AD8606  
R3  
51Ω  
V
V
SCK  
OB  
IB  
V
V
CONVST  
MISO  
CONVST  
SDO  
V
OC  
IC  
AD7091R  
IN  
C9  
4.7nF  
V
V
ID  
OD  
+3.3V  
V
V
RC  
OUT  
GND REGCAP  
DRIVE  
SEL  
GND_ISO  
INPUT  
GND  
GND1  
GND  
ISO  
R4  
R5  
GND_ISO  
C8  
1µF  
–10V TO +10V  
63.4kΩ  
365kΩ  
ISOLATION  
PMOD CON  
12-PIN  
J1  
1
2
VREF  
GND_ISO  
C10  
DNP  
R6  
20kΩ  
GND_ISO  
CON  
GND_ISO  
GND_ISO  
Figure 4. 0 V to 10 V Single Supply Analog to Digital Conversion with Isolation (All connections and Decoupling Not Shown)  
Rev. A | Page 5 of 8  
 
 
CN-0335  
Circuit Note  
Getting Started  
The AD7091 is similar to the AD7091R, but without the voltage  
reference output, and the input range is equal to the power  
supply voltage. The AD7091 can be used with a 2.5 V ADR391  
reference. The ADR391 does not require buffering, therefore a  
single AD8605 can be used in the circuit.  
Load the evaluation software by placing the CN0335 evaluation  
software disc in the CD drive of the PC. You also can download  
the most up to date copy of the evaluation software from  
CN0335 evaluation software. Using "My Computer," locate the  
drive that contains the evaluation software disc and open the  
setup.exe. Follow the on-screen prompts to finish the  
installation. It is recommended to install all software  
components to the default locations.  
The ADR391 is a precision 2.5 V band gap voltage reference,  
featuring low power and high precision (9 ppm/°C of  
temperature drift) in a tiny TSOT package.  
The AD8608 is a quad version of the AD8605 and can be used  
as a substitute for the AD8606, if additional precision op-amps  
are needed.  
Functional Block Diagram  
Figure 5 shows the functional diagram of the test setup.  
Setup  
The AD8601, AD8602 and AD8604 are single, dual, and quad  
rail-to-rail, input and output, single-supply amplifiers featuring  
very low offset voltage and wide signal bandwidth, that can be  
used in place of AD8605, AD8606, and AD8608.  
1. Connect the EVAL-CFTL-6V-PWRZ (+6 V dc power  
supply) to SDP-PMD-IB1Z interposer board via the dc  
barrel jack.  
2. Connect the SDP-PMD-IB1Z (interposer board) to EVAL-  
SDP-CB1Z SDP board via the 120-pin ConA connector.  
3. Connect the EVAL-SDP-CB1Z (SDP board) to the PC via  
the USB cable.  
4. Connect the EVAL-CN0335-PMDZ evaluation board to  
the SDP-PMD-IB1Z interposer board via the 12-pin  
header Pmod connector.  
5. Connect the voltage source (voltage generator) to the  
EVAL-CN0335-PMDZ evaluation board via the terminal  
block J2.  
The AD7457 is a 12-bit, 100 kSPS, low power, SAR ADC, and  
can be used in combination with the ADR391 voltage reference  
in place of AD7091R, when a 300 kSPS throughput rate is not  
needed.  
CIRCUIT EVALUATION AND TEST  
This circuit uses the EVAL-CN0335-PMDZ circuit board, the  
SDP-PMD-IB1Z and the EVAL-SDP-CB1Z system  
demonstration platform (SDP) evaluation board. The  
interposer board SDP-PMD-IB1Z and the SDP board EVAL-  
SDP-CB1Z have 120-pin mating connectors. The interposer  
board and the EVAL-CN0335-PMDZ board have 12-pin Pmod  
matching connectors, allowing quick setup and evaluation of  
the circuit’s performance. The EVAL-CN0335-PMDZ board  
contains the circuit to be evaluated, as described in this note  
and the SDP evaluation board is used with the CN0335  
evaluation software to capture the data from the EVAL-  
CN0335-PMDZ circuit board.  
Test  
Launch the evaluation software. The software communicates to  
the SDP board if the Analog Devices System Development  
Platform drivers are listed in the Device Manager. After USB  
communications are established, the SDP board can be used to  
send, receive, and capture serial data from the EVAL-CN0335-  
PMDZ board. Data can be saved in the computer for various  
values of input voltages. Information and details regarding how  
to use the evaluation software for data capturing can be found  
at CN0335 Software User Guide.  
Equipment Needed  
PC with a USB port Windows® XP or Windows Vista®  
(32-bit), or Windows® 7/8 (64 or 32-bit)  
EVAL-CN0335-PMDZ circuit evaluation board  
EVAL-SDP-CB1Z SDP evaluation board  
SDP-PMD-IB1Z interposer board  
A photo of the EVAL-CN0335-PMDZ board is shown in Figure 6.  
CN0335 evaluation software  
Precision voltage source  
Rev. A | Page 6 of 8  
Circuit Note  
CN-0335  
EVAL-CFTL-6V-PWRZ  
6V WALL WART  
EVAL-SDP-CB1Z  
SDP-B BOARD  
J1  
EVAL-CN0335-PMDZ  
120-PIN  
±10V  
VOLTAGE  
SOURCE  
J1  
PMOD  
J3  
PMOD  
CON A  
USB  
J2  
J4  
SDP-PMD-IB1Z  
INTERPOSER BOARD  
PC  
Figure 5. Test Setup Functional Block Diagram  
Figure 6. Photo of EVAL-CN0335-PMDZ Board  
Rev. A | Page 7 of 8  
 
 
CN-0335  
Circuit Note  
LEARN MORE  
REVISION HISTORY  
CN0335 Design Support Package:  
3/14—Rev. 0 to Rev. A  
http://www.analog.com/CN0335-DesignSupport  
Change to Circuit Function and Benefits Section ........................1  
Chen, Baoxing, John Wynne, and Ronn Kliger. High Speed  
Digital Isolators Using Microscale On-Chip Transformers,  
Analog Devices, 2003  
2/14—Revision 0: Initial Version  
Chen, Baoxing. iCoupler® Products with isoPower™ Technology:  
Signal and Power Transfer Across Isolation Barrier Using  
Microtransformers, Analog Devices, 2006  
Ghiorse, Rich. Application Note AN-825, Power Supply  
Considerations in iCoupler® Isolation Products, Analog  
Devices  
Krakauer, David. “Digital Isolation Offers Compact, Low-Cost  
Solutions to Challenging Design Problems.”Analog Dialogue.  
Volume 40, December 2006.  
MT-031 Tutorial, Grounding Data Converters and Solving the  
Mystery of "AGND" and "DGND," Analog Devices  
MT-101 Tutorial, Decoupling Techniques, Analog Devices  
Wayne, Scott. “iCoupler  
Digital Isolators Protect RS-232, RS-  
®
485, and CAN Buses in Industrial, Instrumentation, and  
Computer Apps, Analog Dialogue, Volume 39, Number 4,  
2005.  
Data Sheets and Evaluation Boards  
AD8606 Data Sheet  
AD7091R Data Sheet  
ADuM5401 Data Sheet  
(Continued from first page) Circuits from the Lab reference designs are intended only for use with Analog Devices products and are the intellectual property of Analog Devices or its licensors.  
While you may use the Circuits from the Lab reference designs in the design of your product, no other license is granted by implication or otherwise under any patents or other intellectual  
property by application or use of the Circuits from the Lab reference designs. Information furnished by Analog Devices is believed to be accurate and reliable. However, Circuits from the  
Lab reference designs are supplied "as is" and without warranties of any kind, express, implied, or statutory including, but not limited to, any implied warranty of merchantability,  
noninfringement or fitness for a particular purpose and no responsibility is assumed by Analog Devices for their use, nor for any infringements of patents or other rights of third parties  
that may result from their use. Analog Devices reserves the right to change any Circuits from the Lab reference designs at any time without notice but is under no obligation to do so.  
©2014 Analog Devices, Inc. All rights reserved. Trademarks and  
registered trademarks are the property of their respective owners.  
CN11649-0-3/14(A)  
Rev. A | Page 8 of 8  

相关型号:

SI9130DB

5- and 3.3-V Step-Down Synchronous Converters

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9135LG-T1

SMBus Multi-Output Power-Supply Controller

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9135LG-T1-E3

SMBus Multi-Output Power-Supply Controller

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9135_11

SMBus Multi-Output Power-Supply Controller

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9136_11

Multi-Output Power-Supply Controller

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9130CG-T1-E3

Pin-Programmable Dual Controller - Portable PCs

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9130LG-T1-E3

Pin-Programmable Dual Controller - Portable PCs

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9130_11

Pin-Programmable Dual Controller - Portable PCs

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9137

Multi-Output, Sequence Selectable Power-Supply Controller for Mobile Applications

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9137DB

Multi-Output, Sequence Selectable Power-Supply Controller for Mobile Applications

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9137LG

Multi-Output, Sequence Selectable Power-Supply Controller for Mobile Applications

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9122E

500-kHz Half-Bridge DC/DC Controller with Integrated Secondary Synchronous Rectification Drivers

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY