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DEM-ADS7804 / 05C

EVALUATION FIXTURE

DEM-ADS7804 / 05C
EVALUATION FIXTURE
FEATURES
q 100kHz 12-BIT ADS7804P AND 16-BIT ADS7805P INCLUDED q 16-BIT BUFFERED PARALLEL OUTPUT q CONNECTOR FOR ALL DIGITAL I / O PINS q CRYSTAL OSCILLATOR BASED 100kHz CONVERT COMMAND GENERATOR q EXTERNAL CONVERT COMAND CONNECTOR q PROTOTYPE AREA
DESCRIPTION
The DEM-ADS7804 / 05C Evaluation Fixture is a fully assembled printed circuit board used to evaluate ADS7804P and ADS7805P. This device incorporates an analog input amplifier (with provisions to bypass this amplifier), a parallel digital output buffer, a crystal oscillator based 100kHz convert command generator, an external convert command connector and a 2.3" x 1.2" breadboard area. The DEM-ADS7804 / 05C achieves full converter performance on a two-layer board. This fixture requires only a single +5V power supply. An optional bipolar power supply connector is provided for the input amplifier and breadboarding.
APPLICATIONS
q EVALUATE ADS7804P AND ADS7805P PERFORMANCE q BREADBOARD COMPLETE ANALOG SYSTEM q EVALUATE SIMPLE TWO-LAYER PCB LAYOUT q INCOMING INSPECTION TEST FIXTURE
· Tucson, AZ 85734 · Street Address: 6730 S. Tucson Blvd. · Tucson, AZ 85706 Telex: 066-6491 · FAX: (602) 889-1510 · Immediate Product Info: (800) 548-6132 LI-448 Printed in U.S.A. November, 1993
TABLE OF CONTENTS
How to Use This Manual .............................................................. 2 PCB Legend ........................................................................ 3 Factory Settings ................................................................... 3-5 Step-by-Step Basic Operations ......................................................... 6 Device ........................................................................ 6 Input Amplifier ................................................................. 6 Offset / Gain Adjust ............................................................... 6 Convert Command Generator ...................................................... 6 Output Format.................................................................. 7 Power Supplies ................................................................. 7 Other Options .................................................................. 7 Pin-Out for Output Connectors......................................................... 7 Wiring Diagram ..................................................................... 8 PCB Component Side ............................................................... 10 PCB Solder Side ................................................................... 11 Installed Component List............................................................. 12 Packing List ....................................................................... 12
HOW TO USE THIS MANUAL
A table and diagrams are included in the "Factory Settings" section showing how the board is configured from the factory. A listing of other components, which are shipped with the board, is also included. The Step-by-Step Basic Operations section describes all of the options. At the end of each step, a figure illustrates factory settings. Items installed are highlighted in those figures. For further details on the OPA671, ADS7804P, ADS7805P, or any other device on the DEM-ADS7804 / 05C, refer to the specific product data sheet.
DEM-ADS7804 / 05
FIGURE 1. PCB Legend.
FACTORY SETTINGS
MAKE SELECTION FOR EACH STEP (1) 1. Device 2. Input Amplifier 3. Offset Adjust Gain Adjust 4. Convert Command 5. Output Format 6. Power Supplies
Buffered full parallel can be read from P6. The following is a listing of "factory settings".
FACTORY SETTINGS ADS7805P installed. OPA671 bypassed. Trim circuit not installed. Trim circuit not installed. On-board 100kHz convert command generator connected to R / C. 12 / 16-bit buffered full-parallel output (P6) 2-pin power block (P2) ready for +5V.
NOTE: (1) Each of these steps is explained in detail in the Step-by-Step Basic Operations section.
TABLE I. Quick Reference to Factory Settings and Other Options.
DEM-ADS7804 / 05
FACTORY SETTINGS (CONT)
Hardware P1 P2 P3 P4 P5 P6 U1 U2 J1-J3 J4 Installed Yes Yes Yes Yes Yes Yes Yes Yes Yes No Comments 3-Pin Power Block 2-Pin Power Block PCB Mount BNC Connector PCB Mount BNC Connector 20 X 2 Header 20 X 2 Shrouded Header 28-Pin Socket for ADS7804P or ADS7805P 8-Pin Socket for OPA671 3 x 1 Headers Refer to Step-by-Step Basic Operations, Step 4B.
U1 P3 P5 B A J1 U2 J2 B A BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 P1 OPTIONAL POWER -V GND +V
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
GND +5 P2 POWER P4
ANALOG INPUT
EXTERNAL R / C
DIGITAL I / O GND
J3 INT EXT R / C SELECT 2 P6 40
J4 Not included
1 PARALLEL OUTPUT 39
FIGURE 2. Hardware Installed.
Jumpers for: J1, J2 J3
Setting "A" "INT"
Comments U2 (Input Amplifier Socket) bypassed Crystal On-Board Convert Command Generator Selected (Outputs 100kHz to R / C) CS Tied LOW BYTE Tied LOW
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
P5 B A J1 J2 B A BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15
Pin 37 to 38 Pin 33 to 34
DIGITAL I / O GND
J3 INT EXT R / C SELECT
J4 Not included
FIGURE 3. Jumpers Installed.
DEM-ADS7804 / 05
FACTORY SETTINGS (CONT)
ICs ADS7804P ADS7805P OPA671 U3 U4 U5, U6 U7 Installed No Yes Yes Yes Yes Yes Yes Comments Included in Package Plugged into 28-Pin Socket (U1) Plugged into 8-Pin Socket (U2) 4-Bit Decade Counter Hex Schmit Inverters 8-Bit Latch 1.000MHz Crystal Oscillator
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
FIGURE 4. ICs Installed.
Resistors R2 R3 R5 R1 R4 R6-R8 R9 Pots RV1, RV2 Capacitors C1, C2, C5, C7-C11 C3, C4 C6
Installed No No No Yes Yes Yes Yes Installed No Installed Yes Yes Yes
C7 R5 R6 R7 C1 R8 C2 OA RV1 GA R1 R2 R3 R4 C4 C3
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
RV2 C5
NOTE: (1) Included in Package.
C8 U7 C9 C10
FIGURE 5. Resistors and Capacitors Installed.
DEM-ADS7804 / 05
STEP-BY-STEP BASIC OPERATIONS
STEP 1 - ADS7804P OR ADS7805P A) To test the ADS7804P, install an ADS7804P in U1. B) To test the ADS7805P, install an ADS7805P in U1. Factory Setting: C3, C4, C5, C6 and 28-pin socket (U1) soldered to the board. ADS7805P plugged into U1.
-V GND P1 OPTIONAL POWER P3 R6 R7 B A J1 C1 U2 J2 R8 C2 B A OA RV1 GA R1 R2 R3 R4 C4 +V
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
RV2 PIN 1 C3 C5
GND +5 P2 POWER
-V GND P1 +V
P4 P5 C6 BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
RV2 GA C2 B OA RV1 R1 R2 R3 R4 C4 PIN 1
GND +5 P2 POWER P4 C5 P5 C6 BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 EXTERNAL R / C R9
ANALOG INPUT R5
EXTERNAL R / C R9
ANALOG INPUT R5
OPTIONAL POWER P3 R6 R7 B A J1 C1 U2 J2 R8
DIGITAL I / O GND
RV2 GA R1 R2 R3 R4 RV1
J3 INT
EXT R / C SELECT 40
U5 U6 J3 INT C9 C10 P6 EXT R / C SELECT 40
PARALLEL OUTPUT
C11 1 PARALLEL OUTPUT 39
-V GND P1
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
RV2 GA C2 B OA RV1 R1 R2 R3 R4 C4 PIN 1 C3 C5
GND +5 P2 POWER P4 P5 C6 BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15
OPTIONAL POWER P3 R6 R7 B A J1 C1 U2 J2 R8
-V GND
EXTERNAL R / C R9
ANALOG INPUT R5
P1 OPTIONAL POWER
-V GND P1 +V
DIGITAL I / O GND
J3 INT
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
RV2 GA C2 B OA RV1 R1 R2 R3 R4 C4 PIN 1
GND +5 P2 POWER P4 C5 P5 C6 BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 EXTERNAL R / C R9
OPTIONAL POWER R8 R6 R7 B A C1 U2 J1 J2
ANALOG INPUT R5
U7 2 J4 C11 1 PARALLEL OUTPUT 39 P6 40
FIGURE 7. Factory Settings for Step 2.
DIGITAL I / O GND
EXT R / C SELECT
EXTERNAL R / C R9
J3 INT EXT R / C SELECT 40
Step 3 - Offset / Gain Adjust Offset Adjust A) To adjust offset, install RV1 (50k) and R3 (33.2k), ground the input, then adjust RV1. See Figure 8 for location of RV1 and R3.
J4 C11 1 PARALLEL OUTPUT 39
C7 U7 J4 C11
FIGURE 9. Factory Settings for Step 4.
DEM-ADS7804 / 05
Step 5 - Parallel or Byte-Reading Output
-V GND P1 OPTIONAL POWER P3 R6 R7 B A J1 C1 U2 J2 R8 C2 B A OA RV1 GA R1 R2 R3 R4 C4 +V
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
RV2 PIN 1 C3 C5
GND +5 P2 POWER P4 P5 C6 BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15
ANALOG INPUT R5
EXTERNAL R / C R9
A) P5 outputs byte-reading and full parallel data - See Figure 10. B) P6 outputs buffered full parallel data-See Figure 11. A rising edge pulse will be output on pin 33 (Data Valid) of P6 signifying the end of a conversion and that data is valid. Data will be from the most recently completed conversion. Be sure to tie pin 33 of P5 to pin 34 of P5 with a jumper. This puts the MSB on pin 1 of P6. Factory Setting: Pin 33 jumpered to pin 34 (P5), P5, P6, U4, U5, U6, C8, C9 and C10 soldered to the board (See Figures 10, 11, and 12).
BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 MSB (04P and 05P) D8 LSB (05P) D9 D10 D11 D12 LSB (04P) D13 D14 D15
DIGITAL I / O GND
J3 INT EXT
R / C SELECT 40
PARALLEL OUTPUT
P5 BUSY CS R / C BYTE D0 LSB (05P) D1 D2 D3 D4 LSB (04P) D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 MSB (04P and 05P)
-V GND P1
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
RV2 GA C2 B OA RV1 R1 R2 R3 R4 C4 PIN 1
GND +5 P2 POWER P4 C5 P5 C6 BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 EXTERNAL R / C R9
OPTIONAL POWER P3 R6 R7 B A J1 C1 U2 J2 R8
DIGITAL I / O GND
ANALOG INPUT R5
DIGITAL I / O GND
J3 INT EXT R / C SELECT 40
PARALLEL OUTPUT
Pin 33 (P5) LOW
Pin 33 (P5) HIGH
FIGURE 10. Location of MSBs and LSBs on P5.
C8 C9 C10
FIGURE 12. Factory Settings for Step 5.
-V GND P1 OPTIONAL POWER P3 R6 R7 B A J1 C1 U2 J2 R8 C2 B A OA RV1 GA R1 R2 R3 R4 C4 +V
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
RV2 PIN 1 C5
GND +5 P2 POWER P4 P5 C6 BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15
ANALOG INPUT R5
EXTERNAL R / C R9
Step 6 - Power Supplies A) A 5V power supply connected to P2 (Power) is all that is required to operate the DEM-ADS7804 / 05C.
DIGITAL I / O GND
J3 INT EXT
R / C SELECT 40
PARALLEL OUTPUT
Pin 33 (P5) LOW 2 P6
-V GND P1
BURR-BROWN CORP. ADS7804 / 05 EVALUATION BOARD
RV2 GA C2 B OA RV1 R1 R2 R3 R4 C4 PIN 1 C5
GND +5 P2 POWER P4 P5 C6 BUSY CS R / C BYTE D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15
GND +5
EXTERNAL R / C R9
OPTIONAL POWER
1 MSB (04P and 05P) Pin 1
PARALLEL OUTPUT LSB (04P) Pin 23 LSB (05P) Pin 31
ANALOG INPUT R5
P2 POWER
Data Valid Pin 33
DIGITAL I / O GND
-V GND
J3 INT
FIGURE 11. Location of MSBs and LSBs on P6.
P1 OPTIONAL POWER
C9 U7 2 J4 C11 1 PARALLEL OUTPUT P6
EXT R / C SELECT 40
FIGURE 13. Factory Settings for Step 6.
DEM-ADS7804 / 05
U3 14 +V 74HCT190 8 4 CLK D / U CTEN LOAD MAX / MIN 15 A B C D RCO INT P4 R4 200 EXT R / C R9 49.9 External R / C U2 2 3 4 C1 + 0.1µF OPA671 6 7 C2 + 0.1µF 13 J3 QD 7 QC 6 QB 2 QA 1 10 +V 9 3 12 5 4 +5V 11 U7 J2 A B R8 4.99k 1.000MHz GND 7 Out
NOTE: This circuit diagram includes the offset and gain circuitry. Refer to pages 3, 4 and 5 for factory settings.
Analog Input
R6 4.99k
FIGURE 14. DEM-ADS7804 / 05C Circuit Diagram.
-V R3 33.2k U1 ADS7805 + VDIG VANA BUSY CS R / C BYTE D0 (LSB) D1 D2 D3 D4 D5 D6 D7 15 D7 16 D6 39 37 1 +V D0 -V D1 D2 D3 D4 D5 D6 D7 D8 +5V +5V +5V +5V +5V D9 D10 D11 D12 D13 D14 D15 2 3 35 33 31 29 27 25 23 21 19 17 15 13 11 9 7 5 3 1 P5 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 D8 D9 D10 D11 D12 D13 D14 D15 2 3 4 5 6 7 8 9 1D 2D 3D 4D 5D 6D 7D 8D 1Q 2Q 3Q 4Q 5Q 6Q 7Q 8Q 19 18 17 16 15 14 13 12 1 11 U5 74HCT574 OE CLK 17 D5 18 D4 19 D3 D0 D1 D2 D3 D4 D5 D6 D7 20 D2 21 D1 22 D0 1 11 23 24 U6 74HCT574 OE CLK 2 3 4 5 6 7 8 9 19 1D 2D 3D 4D 5D 6D 7D 8D 1Q 2Q 3Q 4Q 5Q 6Q 7Q 8Q 18 17 16 15 14 13 12 39 37 35 33 31 29 27 25 23 21 19 17 15 13 11 9 7 5 3 1 P6 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 Parallel Output 25 26 1 2 27 +5V 3 28 U4 74HCT14 4 5 6 13 12 11 10 9 8 C6 + 10µF 1 2 AGND1 REF CAP AGND2 D15 (MSB) D14 D13 D12 D11 D10 D9 D8 DGND 3 4 5 + C3 2.2µF D14 7 8 9 10 11 12 13 14 P1 D13 D12 P2 1 +5V D9 D8 D10 2 D11 + C4 2.2µF D15 6 VIN C5 0.1µF +5V R2 576k RV2 50k +5V R1 33.2k RV1 50k C7 0.1µF C8 0.1µF C9 0.1µF C10 0.1µF C11 0.1µF
DEM-ADS7804 / 05
R7 4.99k
ADS7804P FUNCTION D11(MSB) D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 (LSB) Data Zero Data Zero Data Zero Data Zero BYTE R / C CS BUSY
ADS7805P FUNCTION D15(MSB) D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 (LSB) BYTE R / C CS BUSY
ADS7804 / 05P FUNCTIONS GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND
ADS7804P FUNCTION D11(MSB) D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 (LSB) Data Zero Data Zero Data Zero Data Zero BYTE R / C CS BUSY
ADS7805P FUNCTION D15(MSB) D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 (LSB) BYTE R / C CS BUSY
ADS7804 / 05P FUNCTIONS GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND
TABLE II. Pinout of the Digital I / O Connector (P5). Pin 33 tied to pin 34 on P5 (BYTE is LOW).
TABLE III. Pinout of Buffered Output (P6). Pin 33 tied to pin 34 on P5 (BYTE is LOW).
FIGURE 15. PCB Component Side (Ground Plane).
DEM-ADS7804 / 05
-V GND +V
GND +5
FIGURE 16. PCB Solder Side
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INSTALLED COMPONENT LIST
PACKING LIST
NOTE: (1) For reference only. Equivalent components may be used.
DEM-ADS7804 / 05