Motor de Búsqueda de Datasheet de Componentes Electrónicos |
|
AD558JNZ Datasheet(PDF) 5 Page - Analog Devices |
|
AD558JNZ Datasheet(HTML) 5 Page - Analog Devices |
5 / 8 page Applications–AD558 REV. A –5– The only consideration in selecting a supply voltage is that, in order to be able to use the 0 V to 10 V output range, the power supply voltage must be between +11.4 V and +16.5 V. If, how- ever, the 0 V to 2.56 V range is to be used, power consumption will be minimized by utilizing the lowest available supply voltage (above +4.5 V). TIMING AND CONTROL The AD558 has data input latches that simplify interface to 8- and 16-bit data buses. These latches are controlled by Chip Enable (CE) and Chip Select (CS) inputs. CE and CS are inter- nally “NORed” so that the latches transmit input data to the DAC section when both CE and CS are at Logic “0”. If the ap- plication does not involve a data bus, a “00” condition allows for direct operation of the DAC. When either CE or CS go to Logic “1”, the input data is latched into the registers and held until both CE and CS return to “0”. (Unused CE or CS inputs should be tied to ground.) The truth table is given in Table I. The logic function is also shown in Figure 6. Table I. AD558 Control Logic Truth Table Latch Input Data CE CS DAC Data Condition 0 0 0 0 “Transparent” 1 0 0 1 “Transparent” 0 g 0 0 Latching 1 g 0 1 Latching 00 g 0 Latching 10 g 1 Latching X 1 X Previous Data Latched X X 1 Previous Data Latched NOTES X = Does not matter. g = Logic Threshold at Positive-Going Transition. Figure 6. AD558 Control Logic Function In a level-triggered latch such as that in the AD558 there is an interaction between data setup and hold times and the width of the enable pulse. In an effort to reduce the time required to test all possible combinations in production, the AD558 is tested with tDS = tW = 200 ns at 25°C and 270 ns at TMIN and TMAX, with tDH = 10 ns at all temperatures. Failure to comply with these specifications may result in data not being latched properly. Figure 7 shows the timing for the data and control signals; CE and CS are identical in timing as well as in function. OUTPUT AMP 16 15 14 13 GND VOUT 14k Ω 2k Ω 40k Ω 500 Ω 604 Ω Figure 4. 10.24 V Full-Scale Connection NOTE: Decreasing the scale by putting a resistor in series with GND will not work properly due to the code-dependent currents in GND. Adjusting offset by injecting dc at GND is not recommended for the same reason. GROUNDING AND BYPASSING* All precision converter products require careful application of good grounding practices to maintain full rated performance. Because the AD558 is intended for application in microcom- puter systems where digital noise is prevalent, special care must be taken to assure that its inherent precision is realized. The AD558 has two ground (common) pins; this minimizes ground drops and noise in the analog signal path. Figure 5 shows how the ground connections should be made. OUTPUT AMP 16 15 14 13 GND VOUT SELECT VOUT SENSE VOUT 12 11 (SEE NEXT PAGE) RL GND TO SYSTEM GND TO SYSTEM GND (SEE TEXT) TO SYSTEM VCC +VCC 0.1 µF Figure 5. Recommended Grounding and Bypassing It is often advisable to maintain separate analog and digital grounds throughout a complete system, tying them common in one place only. If the common tie-point is remote and acciden- tal disconnection of that one common tie-point occurs due to card removal with power on, a large differential voltage between the two commons could develop. To protect devices that inter- face to both digital and analog parts of the system, such as the AD558, it is recommended that common ground tie-points should be provided at each such device. If only one system ground can be connected directly to the AD558, it is recom- mended that analog common be selected. POWER SUPPLY CONSIDERATIONS The AD558 is designed to operate from a single positive power supply voltage. Specified performance is achieved for any supply voltage between +4.5 V and +16.5 V. This makes the AD558 ideal for battery-operated, portable, automotive or digital main- frame applications. *For additional insight, “An IC Amplifier Users’ Guide to Decoupling, Grounding and Making Things Go Right For A change,” is available at no charge from any Analog Devices Sales Office. |
Número de pieza similar - AD558JNZ |
|
Descripción similar - AD558JNZ |
|
|
Enlace URL |
Política de Privacidad |
ALLDATASHEET.ES |
¿ALLDATASHEET es útil para Ud.? [ DONATE ] |
Todo acerca de Alldatasheet | Publicidad | Contáctenos | Política de Privacidad | Intercambio de Enlaces | Lista de Fabricantes 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 |