AN-628 APPLICATION NOTE One Technology Way • P.O. Box 9106 • Norwood, MA 02062-9106 • Tel: 781/329-4700 • Fax: 781/326-8703 • www.analog.com ADN2850 Evaluation Kit User Manual By Alan Li 7 STEPS TO EVALUATION KIT SETUP The ADN2850 evaluation kit (EVAL-ADN2850-25) consists of a demonstration board and software for evaluating the ADN2850. It is a user-friendly tool that you can control with your personal computer through the printer port. The driving program is self-contained, so no programming languages or skills are needed. Figure 1 provides an overview of how to set up the kit. 1. INSTALL THE ADN2850 SOFTWARE 2. INSTALL THE DRIVER 6. OPEN THE ADN2850 SOFTWARE AND PROGRAM THE RESISTANCE SETTINGS 3. CONNECT THE PARALLEL PORT CABLE 4. CONFIGURE THE EVALUATION BOARD W1 B1 +5V 7. MEASURE THE RESULT GND 5. APPLY THE POWER SUPPLY Figure 1. Evaluation Kit Setup REV. 0 AN-628 SETTING UP THE ADN2850 EVALUATION BOARD Note: If Windows® displays an error message, such as “Can’t connect to service control manager,” contact the IS department for authority to continue installation. Step 1—Installing the ADN2850 Software To install the ADN2850 software from the Revision G CD, run setup.exe under D:\ADN2850 Evaluation Software Package. During the installation, select Ignore or Yes to bypass error messages if they occur. You may need to install the software a few times to get a successful installation. b. Change the pathname of the driver according to the operating system. • On a Windows 2000 or Window NT® system, enter c:\winnt\system32\drivers\dlportio.sys. • On a Windows XP system, enter Step 2—Installing the Driver for PC Parallel Port Communications In addition to installing the ADN2850 software, you need to install a third-party driver, NTPORT from Upper Canada Technologies (UCT), for access to the PC parallel port. UCT offers a free trial with a nominal license fee after 30 days. c:\windows\system32\drivers\dlportio.sys. c. Click the Install button, then the Start button. If the status message indicates success, the driver is installed and operating. Click OK. 4. Set up the driver for automatic startup. Use the following steps that apply to your operating system. 1. Download the driver from www.uct.on.ca. From the UCT website, download NTPORT.OCX. Save ntport.zip in the default or specified directory. Unzip and extract all the files to the directory. For Windows 2000 and XP Systems a. Go to the Device Manager. • On a Windows 2000 system, click Start → Settings → Control Panel → System → Hardware → Device Manager. 2. Run setup.exe. If the setup procedure indicates file violations during installation, select Ignore to bypass them. • On a Windows XP system, click Start →Control Panel →System → Hardware → Device Manager. 3. Ensure that the driver file, dlportio.sys, is in the correct system directory. a. Run loaddrv.exe under c:\program files\project1 or the specified directory. A dialog box appears. –2– REV. 0 AN-628 b. Locate Non-Plug and Play Drivers and dlportio in the Device Manager. If the Non-Plug and Play Drivers entry is not visible, click the View menu in Device Manager and select Show Hidden Devices to make sure that hidden driver files are listed. If you do not see dlportio, reboot Windows, or rerun loaddrv.exe and then reboot Windows. c. Double-click dlportio in the Non-Plug and Play Drivers list. The dlportio Properties page appears. d. At the Driver tab, select Startup Type as Automatic, click Current status to Start, and click OK. Note: If Startup is not active and you cannot change Type, your computer may be administered by your IS department. You may need to consult them to change your PC administrative setting. REV. 0 –3– AN-628 For Windows NT Systems a. From the Windows NT Control Panel, select the Devices icon. The Devices dialog box appears. • For dual supplies, connect JP15 and JP12 to connect the –5V pin to VSS of U1 and U3. Warning: Apply +2.5 V to Pin +5V and –2.5 V to Pin –5V instead. • Select the states of PR and WP from the DIP switches on the evaluation board. • SDO can be monitored at TPSDO. Step 5—Applying the Power Supply Provide a power supply to the ADN2850 evaluation board according to Step 4 for a single supply or for dual supplies. Step 6—Using the Evaluation Board To open the ADN2850 software program, from Windows click Start → Programs → ADN2850 Rev G. b. Select dlportio and click the Startup button. The device Startup Type dialog box appears. From the option buttons, select Automatic, and then click OK. Figure 2 shows the graphical interface. In the Direct Control pane, on the right, you can move the scroll bars or click the buttons to control the device. In the top pane, you can adjust the bit pattern and then click Run to program the device. In the bottom pane, you can approximate RWA and RWB by first entering the measured RAB after power is applied. Step 7—Measuring the Result Use a multimeter to measure the result of your program applications on the ADN2850 evaluation board. UNINSTALLING SOFTWARE To uninstall the ADN2850 software and NTPORT driver, use Add/Remove Programs in the Control Panel. Step 3—Connecting the Parallel Port Cable Connect the parallel port cable from LPT1 on your PC to the ADN2850 evaluation board. TECHNICAL SUPPORT Due to the variations in computer platforms and configurations, Analog Devices, Inc., cannot guarantee the software described in this application note to work on all systems. If you encounter problems, send email to [email protected] or call 1-408-382-3082 for applications support. If you are interested in the ADN2850 source code, send email to [email protected] for more information. Step 4—Configuring the Evaluation Board Follow these requirements to configure the ADN2850 evaluation board: • For a single supply, connect JP14 and JP13 to ground V SS of U1 and U3. Apply 5 V to Pin +5V. Note: Some boards do not come with jumper caps. You should supply suitable caps or simply short the jumpers for proper operation. –4– REV. 0 AN-628 Figure 2. ADN2850 Software Graphical Interface REV. 0 –5– AN-628 section). Other op amps in PDIP can replace the AD820. For a single-supply, 2.5 V voltage reference, AD1582 can be used to offset the op amp bias point for ac operation. EVALUATION BOARD SCHEMATIC The general-purpose op amp AD820, U3A can be configured as various building block circuits in conjunction with the ADN2850 for various circuit evaluations (see the Applications ADN2850 MAIN CIRCUIT +5 +5V (LOWER TO +2.5V IF DUAL SUPPLIES) R2 10k R3 10k C10 4.7F R4 10k C11 0.1F DGND J1 13 25 12 24 11 23 10 22 9 21 8 20 7 19 6 18 5 17 4 16 3 15 2 14 1 U1A ADN2850CSP 16 15 14 13 TPSDO SDI CLK RDY CS 1 +5 TPCLK S1 LOW 1 8 2 7 3 6 4 5 SW-DIP4 W1 B1 B2 W2 R1 1k TPSDI 12 PR 11 WP 10 VDD 9 A2 SDO 2 GND 3 VSS 4 A1 TP/CS TPRDY TP/PR TP/WP HIGH 5 6 7 8 A1 W1 B1 R_CS 100 R_CLK 100 1 R_SDI 100 CLK SDI SDO GND VSS A1 W1 B1 2 3 4 5 DB25 6 7 8 NOTES SIGNAL GROUND WITH NET DGND POWER GROUND WITH NET AGND 16 RDY CS PR WP VDD A2 W2 B2 15 A2 14 13 12 W2 11 10 9 B2 U1B ADN2850TSSOP JP14 GND HEADER C12 0.1F JP15 C13 4.7F –5V HEADER –5 (LOWER TO –2.5V IF DUAL SUPPLIES) ADDITIONAL OP AMP FOR GENERAL-PURPOSE APPLICATIONS V+ V– VO JP7 JP9 JP5 HEADER JP6 JP8 C5 0.1F +5 JP4 HEADER 2 JP2 HEADER VI_DC 7 1, 5, 8 – U3A AD820AR 6 VO 3 + 4 JP3 HEADER C9 JP10 JP11 JP1 VI_AC U2 AD1582 GND +5 3 C7 0.1F JP12 HEADER 2 VIN 1 VOUT 2.5 VREF JP13 HEADER C6 –5 0.1F C8 0.1F +5 2 7 U3B AD820AN 3 + 1 8 – 4 6 5 REPLACEABLE OP AMP IN PDIP Figure 3. Evaluation Board Schematic –6– REV. 0 AN-628 Table I. ADN2850 24-Bit Serial Data-Word MSB RDAC Instruction Byte 0 C3 C2 C1 C0 0 0 Data Byte 1 0 A0 X EEMEM C3 C2 C1 C0 A3 A2 A1 X X X X Data Byte 0 X LSB D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 A0 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Command bits are C0–C3. Addresses bits are A3–A0. Data bits D0–D9 are applicable to the RDAC wiper register, whereas D0–D15 are applicable to the EEMEM register. Command instruction codes are defined in Table II. Table II. ADN2850 Instruction/Operation Truth Table 1, 2, 3 Instruction Byte 0 Data Byte 1 Instruction B23 • • • • • • • • • • • • • • • • • B16 B15 • • • B8 No. C3 C2 C1 C0 A3 A2 A1 A0 X • • • D9 D8 Data Byte 0 B7 • • • B0 D7 • • • D0 Operation 0 0 0 0 0 X X X X X•••X X X••• X NOP: Do nothing. See Table V. 1 0 0 0 1 0 0 0 A0 X•••X X X••• X Write the contents of EEMEM(A0) to RDAC(A0). This command leaves the device in the read program power state. To return the device to the idle state, perform NOP instruction 0. See Table V. 2 0 0 1 0 0 0 0 A0 X•••X X X••• X Save wiper setting: Write the contents of RDAC(A0) to EEMEM(A0). See Table IV. 34 0 0 1 1 A3 A2 A1 A0 D15 • • • D8 D7• • • D0 Write the contents of serial register data bytes 0 and 1 (total 16-bit) to EEMEM(ADDR). See Table VII. 45 0 1 0 0 0 X•••X X X••• X Decrement 6 dB: Right-shift contents of RDAC(A0), stops at all ”zeros.” 55 0 1 0 1 X X X X X•••X X X••• X Decrement all 6 dB: Right-shift contents of all RDAC registers, stops at all ”zeros.” 65 0 1 1 0 0 X•••X X X••• X Decrement contents of RDAC(A0) by ”one,” stops at all ”zeros.” 75 0 1 1 1 X X X X X•••X X X••• X Decrement contents of all RDAC registers by “one,” stops at all “zeros.” 8 1 0 0 0 0 X•••X X X••• X Reset: Load all RDACs with their corresponding EEMEM previously saved values. 9 1 0 0 1 A3 A2 A1 A0 X•••X X X••• X Write contents of EEMEM(ADDR) to serial register data bytes 0 and 1. SDO activated. See Table VIII. 10 1 0 1 0 0 0 0 A0 X•••X X X••• X Write contents of RDAC(A0) to serial register data bytes 0 and 1. SDO activated. See Table IX. 11 1 0 1 1 0 0 0 A0 X • • • D9D8 D7 • • • D0 Write contents of serial register data bytes 0 and 1 (total 10-bit) to RDAC(A0). See Table III. 125 1 1 0 0 0 0 0 A0 X•••X X X••• X Increment 6 dB: Left-shift contents of RDAC(A0), stops at all “ones.” See Table VI. 135 1 1 0 1 X X X X X•••X X X••• X Increment all 6 dB: Left-shift contents of all RDAC registers, stops at all “Ones.” 145 1 1 1 0 0 X•••X X X••• X Increment contents of RDAC(A0) by “one,” stops at all “ones.” See Table IV. 155 1 1 1 1 X X X X X•••X X X••• X Increment contents of all RDAC registers by “one,” stops at all “ones.” 0 0 0 0 0 0 0 0 A0 A0 0 A0 NOTES 1. The SDO output shifts out the last 24 bits of data clocked into the serial register for daisy-chain operation. Exception: For any instruction following instruction 9 or 10, the selected internal register data will be present in data byte 0 and 1. The instructions following 9 and 10 must also be a full 24-bit data-word to completely clock out the contents of the serial register. 2. The RDAC register is a volatile scratchpad register that is refreshed at power-on from the corresponding nonvolatile EEMEM register. 3. Execution of the above operations takes place when the CS strobe returns to logic high. 4. Instruction 3 writes two data bytes (total 16-bit) to EEMEM. However, in the cases of addresses 0 and 1, only the last 10 bits are valid for wiper position setting. 5. The increment, decrement, and shift commands ignore the contents of the shift register data bytes 0 and 1. REV. 0 –7– AN-628 Table VI. Using Left Shift by One to Increment 6 dB Steps PROGRAMMING EXAMPLES The following programming examples illustrate the typical sequence of events for various features of the ADN2850. Refer to Table II for the instructions and dataword format. The instruction numbers, addresses, and data appearing at the SDI and SDO pins are displayed in hexadecimal format in the tables. SDI SDO C0XXXXH XXXXXXH Moves wiper 1 to double the present data contained in the RDAC1 register. C1XXXXH C0XXXXH Table III. Scratchpad Programming SDI SDO B00100H XXXXXXH Loads data 100H into the RDAC1 register. Wiper 1 moves to the 1/4 full-scale position. B10200H B00100H Table VII. Storing Additional User Data in EEMEM Loads data 200H into the RDAC2 register. Wiper 2 moves to the 1/2 full-scale position. SDI SDO B00100H XXXXXXH Loads data 100H into the RDAC1 register. Wiper 1 moves to the 1/4 full-scale position. E0XXXXH B00100H 20XXXXH E0XXXXH Moves wiper 2 to double the present data contained in the RDAC2 register. Action Table IV. Incrementing RDAC Followed by Storing the Wiper Setting to EEMEM E0XXXXH Action SDI SDO 32AAAAH XXXXXXH Stores data AAAAH into spare EEMEM location USER1. Allowable to address in 13 locations with maximum 16 bits of data. 335555H 32AAAAH Action Action Stores data 5555H into spare EEMEM location USER2. Allowable to address 13 locations with maximum 16 bits of data. Table VIII. Reading Back Data from Various Memory Locations Increments the RDAC1 register by one to 101H. Increments the RDAC1 register by one to 102H. Continue until the desired wiper position is reached. SDI SDO 92XXXXH XXXXXXH Prepares data read from USER1 location. 00XXXXH 92AAAAH XXXXXXH Saves RDAC1 register data into EEMEM1. Optionally tie WP to GND to protect EEMEM values. Action NOP instruction 0 sends 24-bit word out of SDO where the last 16 bits contain the contents of USER1 location. NOP command ensures device returns to idle power dissipation state. Table IX. Reading Back Wiper Setting Table V. Restoring EEMEM Values to RDAC Registers SDI SDO 10XXXXH XXXXXXH Action Restores EEMEM1 value to RDAC1 register. 00XXXXH 10XXXXXH NOP. Recommended step to minimize power consumption. 8XXXXXH 00XXXXH Resets EEMEM1 and EEMEM2 values to RDAC1 and RDAC2 registers, respectively. SDI SDO Action B00200H XXXXXXH Sets RDAC1 to midscale. C0XXXXH B00200H Doubles RDAC1 from midscale to full scale. A0XXXXH C0XXXXH Prepares reading wiper setting from RDAC1 register. XXXXXXH A003FFH Reads back full-scale value from RDAC1 register. EEMEM values for RDACs can be restored by power-on, strobing the PR pin or programming as shown above. –8– REV. 0 AN-628 APPLICATIONS U1 ADN2850 1 3 4 5 VI R1 6 A RDAC B 7 8 16 RDY CS PR WP VDD A2* W2 B2 CLK SDI SDO GND VSS A1* W1 B1 2 15 14 13 12 –INPUT VO 11 1 1 9 +5 (+2.5V) R1 JP6 JP15 –5 (–2.5V) –RWB R1 VO = VI = 0.1V R1 = 5k, RAB = 10k 10 VO G= 0V 6 U3 AD820AR 3 + 1 –VI (D RAB) (2n R1) –200mV – JP4 VI_DC 1, 5, 8 7 2 0 0.5 1.0 V(VO) VO POTSETTING 4 JP1 JP12 –5 (–2.5V) Figure 4. Inverting Linear Gain and Attenuator FB U1 ADN2850 2 3 4 5 VI A RDAC B 6 R2 7 8 1 RDY CS PR WP VDD A2* W2 B2 CLK SDI SDO GND VSS A1* W1 B1 16 15 14 13 –INPUT VO 12 1 1 10 9 JP8 +5 (+2.5V) JP4 VI_DC 2 1 JP3 VI_AC C9 1, 5, 8 7 –100mV – U3 AD820AR –5 (–2.5V) G = –R2 RWA –VI (2n R2) VO = (2n –D) RAB VI = 0.1V RAB = 10k, R2 = 10k R2 VO JP15 –10V 11 LOG 1 3 + 1 JP1 6 VO 4 JP12 –5 (–2.5V) Figure 5. Inverting Exponential Gain and Attenuator REV. 0 –9– 0 0.5 V(VO) POTSETTING 1.0 AN-628 U1 ADN2850 1 CLK SDI SDO GND VSS A1* W1 B1 2 3 4 5 R1 6 A RDAC B 7 8 RDY CS PR WP VDD A2* W2 B2 16 15 14 13 12 –INPUT VO 11 1 1 300mV VI = 0.1V R1 = 5k, RAB = 10k 10 9 VO +5 VI JP14 JP5 G = 1 + RWB R1 R1 JP6 VI_DC 1, 5, 8 7 0V – 6 U3 AD820AR 3 + 1 D RAB VO = VI 1+ n 2 R1 2 0 0.5 1.0 V(VO) VO POTSETTING 4 JP2 JP13 Figure 6. Noninverting Linear Gain 1 U1 ADN2850 1 CLK SDI SDO GND VSS A1* W1 B1 2 3 4 5 A RDAC B 6 R2 7 8 RDY CS PR WP VDD A2* W2 B2 16 15 14 13 –INPUT 12 1 VO 1 11 R2 10 9 JP8 VO VI +5 JP14 G = 1 + R2 RWA VO = VI 1 + 2 VI_DC 2n R2 (2n –D) RAB JP2 1 U3 AD820AR 3 + JP3 VI_AC 1, 5, 8 7 – 6 VO 4 JP13 C9 1 Figure 7. Noninverting Exponential Gain –10– REV. 0 AN-628 PCB LAYOUT Figure 8. Top Layer Figure 9. Bottom Layer REV. 0 –11– AN-628 Figure 10. Top Overlay Silkscreen –12– REV. 0 AN-628 PCB LAYOUT CONSIDERATIONS To stabilize voltage supplies, bypass Pin +5V and Pin –5V with a 4.7 mF or 10 mF capacitor with proper polarities. Adding 0.1 mF decoupling capacitors, very close to the supply pins of the active component, can minimize high frequency noise as well. Table X. PCB Parts List Designator Footprint TPSDO TPCLK TPSDI TP/CS +5V GND B1 W1 A1 VI_DC VI_AC C9 A2 W2 B2 –5V VO V– V+ JP8 JP9 JP7 JP6 JP1 JP11 JP10 Test point 0.09 Test point 0.09 Test point 0.09 Test point 0.09 Post pin 0.125 Post pin 0.125 Post pin 0.125 Post pin 0.125 Post pin 0.125 Post pin 0.125 Post pin 0.125 RAD 0.1 Post pin 0.125 Post pin 0.125 Post pin 0.125 Post pin 0.125 Post pin 0.125 Post pin 0.125 Post pin 0.125 Jumper 0.3 Jumper 0.3 Jumper 0.3 Jumper 0.3 Jumper 0.3 Jumper 0.3 Jumper 0.3 REV. 0 Comment Designator Footprint TPRDY TP/WP TP/PR DGND C12 C7 C11 C6 C5 R_/CS R_CLK R_SDI R4 R3 R2 R1 C8 C13 C10 U2 U1B U1A Test point 0.09 Test point 0.09 Test point 0.09 DGNDPAD RAD 0.1 RAD 0.1 RAD 0.1 RAD 0.1 RAD 0.1 Axial 0.3 Axial 0.3 Axial 0.3 Axial 0.3 Axial 0.3 Axial 0.3 Axial 0.3 RAD 0.2 RAD 0.2 RAD 0.2 SOT-23 TSSOP-16 LFCSP-16 5 mm ¥ 5 mm DIP8 SO-8 DB25SL SIP2 SIP2 SIP2 SIP2 SIP2 SIP2 SIP2 SIP2 DIP8 U3B U3A J1 JP15 JP14 JP5 JP3 JP2 JP4 JP12 JP13 S1 –13– Comment 0.1 mF 0.1 mF 0.1 mF 0.1 mF 0.1 mF 100 W 100 W 100 W 10 kW 10 kW 10 kW 1 kW 1 mF 4.7 mF 4.7 mF AD1582 ADN2850TSSOP ADN2850CSP AD820AN AD820AR DB25 Header Header Header Header Header Header Header Header SW-DIP4 AN-628 ADN2850 PARALLEL PORT CONNECTION (For Visual Basic Program Developers Only) GND 13 12 25 S7 11 24 S6 10 23 S5 CS CLK SDI D7 D6 D5 D4 D3 D2 D1 D0 9 8 7 6 5 4 3 2 22 S4 PR 21 20 19 18 17 16 1 14 15 SDO S3 C3 NOTE 8 OUTPUT PINS ACCESSED VIA THE DATA PORT 5 INPUT PINS (1 INVERTED) ACCESSED VIA THE STATUS PORT 4 OUTPUT PINS (3 INVERTED) ACCED VIA THE CONTROL PORT REMAINING 8 PINS ARE GROUNDED C2 C1 C0 (NTPORT1.ADDRESS = 888) (NTPORT1.ADDRESS = 889) (NTPORT1.ADDRESS = 890) Figure 11. Parallel Port Connector Configuration (For VB Program Developers Only) TIMING DEFINITION (In Visual Basic Source Code cmdRUN) BIT 3 PR (PIN 5) BIT 2 CS (PIN 4) BIT 1 CLK (PIN 3) BIT 0 SDI (PIN 2) BINARY CODE 1100 DECIMAL CODE 12 1001 1011 1000 1010 1100 9 11 8 10 12 SEND OUT NO ACTIVITY BIT_TOGO = 1 SEND OUT BIT_TOGO = 0 LATCH DATA Figure 12. Timing Definition (For VB Program Developers Only) –14– REV. 0 AN-628 REV. 0 –15– E03555–0–3/03(0) © 2003 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective companies. –16–