 |
データシートサーチシステム |
|
|
データシートサーチシステム |
|
AD5313 データシート(PDF) 19 Page - Analog Devices |
|
|
|||||||||||||||||||||||||||||
AD5313 データシート(HTML) 19 Page - Analog Devices |
|
|
19 / 24 page  Data Sheet AD5304/AD5314/AD5324 Rev. H | Page 19 of 24 Opto-Isolated Interface for Process Control Applications The AD5304/AD5314/AD5324 have a versatile 3-wire serial inter-face, making them ideal for generating accurate voltages in process control and industrial applications. Due to noise, safety requirements, or distance, it might be necessary to isolate the AD5304/AD5314/AD5324 from the controller. This can easily be achieved by using opto-isolators, which provide isolation in excess of 3 kV. The actual data rate achieved is limited by the type of optocouplers chosen. The serial loading structure of the AD5304/AD5314/AD5324 makes them ideally suited for use in opto-isolated applications. Figure 42 shows an opto-isolated interface to the AD5304 where DIN, SCLK, and SYNC are driven from optocouplers. The power supply to the part also needs to be isolated. This is done by using a transformer. On the DAC side of the transformer, a 5 V regulator provides the 5 V supply required for the AD5304. SCLK DIN AD5304 SYNC GND 5V REGULATOR POWER VDD 10µF 0.1µF REFIN VDD 10kΩ 10kΩ 10kΩ DIN SYNC SCLK VDD VDD VOUTA VOUTB VOUTC VOUTD Figure 42. AD5304 in an Opto-Isolated Interface DECODING MULTIPLE AD5304/AD5314/AD5324S The SYNC pin on the AD5304/AD5314/AD5324 can be used in applications to decode a number of DACs. In this application, all the DACs in the system receive the same serial clock and serial data, but SYNC can only be active to one of the devices at any one time, allowing access to four channels in this 16-channel system. The 74HC139 is used as a 2-to-4-line decoder to address any of the DACs in the system. To prevent timing errors, the enable input must be brought to its inactive state while the coded address inputs are changing state. Figure 43 shows a diagram of a typical setup for decoding multiple AD5304 devices in a system. 74HC139 ENABLE CODED ADDRESS 1G 1A 1B DGND 1Y0 1Y1 1Y2 1Y3 SCLK DIN VCC VDD DIN SCLK AD5304 SYNC DIN SCLK AD5304 SYNC DIN SCLK AD5304 SYNC DIN SCLK AD5304 SYNC VOUTA VOUTB VOUTC VOUTD VOUTA VOUTB VOUTC VOUTD VOUTA VOUTB VOUTC VOUTD VOUTA VOUTB VOUTC VOUTD Figure 43. Decoding Multiple AD5304 Devices in a System AD5304/AD5314/AD5324 as a Digitally Programmable Window Detector A digitally programmable upper/lower limit detector using two DACs in the AD5304/AD5314/AD5324 is shown in Figure 44. The upper and lower limits for the test are loaded to DAC A and DAC B, which, in turn, set the limits on the CMP04. If the signal at the VIN input is not within the programmed window, an LED indicates the fail condition. Similarly, DAC C and DAC D can be used for window detection on a second VIN signal. *ADDITIONAL PINS OMITTED FOR CLARITY. 5V 1/2 CMP04 FAIL PASS 1/6 74HC05 VREF SCLK DIN VOUTA VDD 1/2 AD5304/AD5314/ AD5324* REFIN GND 0.1µF 10µF 1kΩ 1kΩ VIN PASS/FAIL DIN SCLK SYNC SYNC VOUTB Figure 44. Window Detection |
|
|
リンク URL |
| ALLDATASHEETはお客様のビジネスに役立ちますか？ [ DONATE ] |
Alldatasheetは | 広告 | お問い合わせ | プライバシーポリシー | データシートへのリンク | リンク交換 | メーカーリスト All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
Japanese ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
