Zakładka z wyszukiwarką danych komponentów |
|
ADS574 Arkusz danych(PDF) 11 Page - Texas Instruments |
|
ADS574 Arkusz danych(HTML) 11 Page - Texas Instruments |
11 / 17 page 11 ® ADS574 tion Mode, system throughput can be speeded up, since the input to the ADS574 can start slewing before the end of a conversion (after the acquisition time), which is not possible with existing ADC574s. INSTALLATION LAYOUT PRECAUTIONS Analog (pin 9) and digital (pin 15) commons are not con- nected together internally in the ADS574, but should be connected together as close to the unit as possible and to an analog common ground plane beneath the converter on the component side of the board. In addition, a wide conductor pattern should run directly from pin 9 to the analog supply common, and a separate wide conductor pattern from pin 15 to the digital supply common. If the single-point system common cannot be established directly at the converter, pin 9 and pin 15 should still be connected together at the converter. A single wide conductor pattern then connects these two pins to the system common. In either case, the common return of the analog input signal should be referenced to pin 9 of the ADC. This prevents any voltage drops that might occur in the power supply common returns from appearing in series with the input signal. systems (due to multiplexers, sample/holds, etc. in front of the converter) does not affect the accuracy of the ADS574 conversion in the Emulation Mode. In both modes, as soon as the conversion is completed the internal sample/hold circuit immediately begins slewing to track the input signal. Basically, the Control Mode is provided to allow full use of the internal sample/hold, eliminating the need for an exter- nal sample/hold in most applications. As compared with systems using separate sample/hold and A/D, the ADS574 in the Control Mode also eliminates the need for one of the control signals, usually the convert command. The com- mand that puts the internal sample/hold in the hold state also initiates a conversion, reducing timing constraints in many systems. The Emulation Mode allows the ADS574 to be dropped into almost all existing ADC574 sockets without changes to any other existing system hardware or software. The input to the ADS574 in the Emulation Mode does not need to be stable before a convert command is received, so that multiplexers, programmable gain amplifiers, etc., can be slewing quickly any time before a convert command is given as long as the analog input to the ADS574 is stable after the convert command is received, as it needs to be in existing ADC574 systems for accurate operation. In fact, even in the Emula- S/H CONTROL MODE ADC574 EMULATION MODE (Pin 11 Connected to +5V) (Pin 11 Connected to 0V to –15V) SYMBOL PARAMETER MIN TYP MAX MIN TYP MAX UNITS tAQ + tC Throughput Time: 12-bit Conversions 22 25 22 25 µs 8-bit Conversions 16 18 16 18 µs tC Conversion Time: 12-bit Conversions 18 18 µs 8-bit Conversions 12 12 µs tAQ Acquisition Time 4 4 µs tAP Aperture Delay 20 4000 ns tJ Aperture Uncertainty 0.3 30 ns TABLE VI. Conversion Timing, T MIN to T MAX . FIGURE 9. Signal Acquisition and Conversion Timing. Signal Acquisition Conversion Signal Acquisition t AP Signal Acquisition Conversion Signal Acquisition t C t AQ t C t AQ t AP R/C S/H Control Mode Pin 11 connected to +5V. ADC574 Emulation Mode* Pin 11 connected to V EE or ground. *In the ADC574 Emulation Mode, a convert command triggers a delay that allows the ADS574 enough time to acquire the input signal before converting. |
Podobny numer części - ADS574 |
|
Podobny opis - ADS574 |
|
|
Link URL |
Polityka prywatności |
ALLDATASHEET.PL |
Czy Alldatasheet okazała się pomocna? [ DONATE ] |
O Alldatasheet | Reklama | Kontakt | Polityka prywatności | Linki | Lista producentów 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 |