Os motores de busca de Datasheet de Componentes eletrônicos
  Portuguese  ▼
ALLDATASHEETPT.COM

X  

AD7394 Folha de dados(PDF) 10 Page - Analog Devices

Nome de Peças AD7394
Descrição Electrónicos  3 V, Dual, Serial Input 12-/10-Bit DACs
Download  12 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Fabricante Electrônico  AD [Analog Devices]
Página de início  http://www.analog.com
Logo AD - Analog Devices

AD7394 Folha de dados(HTML) 10 Page - Analog Devices

Back Button AD7394 Datasheet HTML 4Page - Analog Devices AD7394 Datasheet HTML 5Page - Analog Devices AD7394 Datasheet HTML 6Page - Analog Devices AD7394 Datasheet HTML 7Page - Analog Devices AD7394 Datasheet HTML 8Page - Analog Devices AD7394 Datasheet HTML 9Page - Analog Devices AD7394 Datasheet HTML 10Page - Analog Devices AD7394 Datasheet HTML 11Page - Analog Devices AD7394 Datasheet HTML 12Page - Analog Devices  
Zoom Inzoom in Zoom Outzoom out
 10 / 12 page
background image
AD7394/AD7395
–10–
REV. 0
POWER SUPPLY
The very low power consumption of the AD7394/AD7395 is a
direct result of a circuit design optimizing the use of a CBCMOS
process. By using the low power characteristics of CMOS for
the logic, and the low noise, tight matching of the complemen-
tary bipolar transistors, excellent analog accuracy is achieved.
One advantage of the rail-to-rail output amplifiers used in the
AD7394/AD7395 is the wide range of usable supply voltage.
The part is fully specified and tested for operation from +2.7 V
to +5.5 V.
POWER SUPPLY BYPASSING AND GROUNDING
Local supply bypassing consisting of a 10
µF tantalum electro-
lytic in parallel with a 0.1
µF ceramic capacitor is recommended
in all applications (Figure 21).
C
*
0.1 F
10 F
AD7394
OR
AD7395
CS
CLK
LDA, B
RS
SDI
DGND
VOUTB
VOUTA
*OPTIONAL EXTERNAL
REFERENCE BYPASS
REF
VDD
AGND
+2.7V TO +5.5V
Figure 21. Recommended Supply Bypassing for the
AD7394/AD7395
INPUT LOGIC LEVELS
All digital inputs are protected with a Zener-type ESD protec-
tion structure (Figure 22) that allows logic input voltages to
exceed the VDD supply voltage. This feature can be useful if the
user is driving one or more of the digital inputs with a 5 V CMOS
logic input-voltage level while operating the AD7394/AD7395
on a +3 V power supply. If this mode of interface is used, make
sure that the VOL of the 5 V CMOS meets the VIL input re-
quirement of the AD7394/AD7395 operating at 3 V. See Figure
12 for a graph of digital logic input threshold versus operating
VDD supply voltage.
VDD
LOGIC
IN
GND
Figure 22. Equivalent Digital Input ESD Protection
In order to minimize power dissipation from input logic levels
that are near the VIH and VIL logic input voltage specifications,
a Schmitt trigger design was used that minimizes the input-
buffer current consumption compared to traditional CMOS
input stages. Figure 11 is a plot of incremental input voltage
versus supply current showing that negligible current consump-
tion takes place when logic levels are in their quiescent state.
The normal crossover current still occurs during logic transi-
tions. A secondary advantage of this Schmitt trigger is the pre-
vention of false triggers that would occur with slow moving
logic transitions when a standard CMOS logic interface or opto
isolators are used. The logic inputs SDI, CLK,
CS, LDA, LDB,
RS, SHDN all contain the Schmitt trigger circuits.
DAC B REGISTER
DP
R
CS
CLK
SHIFT
REGISTER
Q
DAC A REGISTER
DP
R
LDA LDB
RS MSB
SDI
EN
Figure 23. Equivalent Digital Interface Logic
DIGITAL INTERFACE
The AD7394/AD7395 has a serial data input. A functional
block diagram of the digital section is shown in Figure 23, while
Table I contains the truth table for the logic control inputs.
Three pins control the serial data input register loading. Two
additional pins determine which DAC will receive the data
loaded into the input shift register. Data at the SDI is clocked
into the shift register on the rising edge of the CLK. Data is
entered in the MSB-first format. The active low chip select (
CS)
pin enables loading of data into the shift register from the SDI
pin. Twelve clock pulses are required to load the 12-bit AD7390
DAC shift register. If additional bits are clocked into the shift
register, for example, when a microcontroller sends two 8-bit
bytes, the MSBs are ignored (Table IV). The lowest resolution
AD7395 is also loaded MSB-first with 10 bits of data. Again, if
additional bits are clocked into the shift register only the last 10
bits clocked in are used. When
CS returns to logic high, shift-
register loading is disabled. The load pins
LDA and LDB con-
trol the flow of data from the shift register to the DAC register.
After a new value is clocked into the serial-input register, it will
be transferred to the DAC register associated with its
LDA or
LDB logic control line. Note, if the user wants to load both
DAC registers with the current contents of the shift register,
both control lines
LDA and LDB should be strobed together.
The
LDA and LDB pins are level-sensitive and should be re-
turned to logic high prior to any new data being sent to the
input shift register to avoid changing the DAC register values.
See Truth Table for complete set of conditions.
RESET (
RS) PIN
Forcing the asynchronous
RS pin low will set the DAC register
to all zeros, or midscale, depending on the logic level applied to
the MSB pin. When the MSB pin is set to logic high, both DAC
registers will be reset to midscale (i.e., the DAC Register’s MSB
bit will be set to Logic 1 followed by all zeros). The reset func-
tion is useful for setting the DAC outputs to zero at power-up or
after a power supply interruption. Test systems and motor
controllers are two of many applications that benefit from
powering up to a known state. The external reset pulse can be


Nº de peça semelhante - AD7394

Fabricante ElectrônicoNome de PeçasFolha de dadosDescrição Electrónicos
logo
Analog Devices
AD7390 AD-AD7390 Datasheet
342Kb / 12P
   3 Volt Serial-Input Micropower 10-Bit & 12-Bit DACs
REV. 0
AD7390 AD-AD7390 Datasheet
203Kb / 12P
   3 V Serial-Input Micropower 10-Bit and 12-Bit DACs
REV. A
AD7390 AD-AD7390 Datasheet
203Kb / 12P
   3 V Serial-Input Micropower 10-Bit and 12-Bit DACs
REV. A
AD7390AN AD-AD7390AN Datasheet
342Kb / 12P
   3 Volt Serial-Input Micropower 10-Bit & 12-Bit DACs
REV. 0
AD7390AN AD-AD7390AN Datasheet
203Kb / 12P
   3 V Serial-Input Micropower 10-Bit and 12-Bit DACs
REV. A
More results

Descrição semelhante - AD7394

Fabricante ElectrônicoNome de PeçasFolha de dadosDescrição Electrónicos
logo
Analog Devices
AD7391ANZ AD-AD7391ANZ Datasheet
203Kb / 12P
   3 V Serial-Input Micropower 10-Bit and 12-Bit DACs
REV. A
AD7390 AD-AD7390 Datasheet
203Kb / 12P
   3 V Serial-Input Micropower 10-Bit and 12-Bit DACs
REV. A
AD7390 AD-AD7390_15 Datasheet
203Kb / 12P
   3 V Serial-Input Micropower 10-Bit and 12-Bit DACs
REV. A
AD7391 AD-AD7391_15 Datasheet
203Kb / 12P
   3 V Serial-Input Micropower 10-Bit and 12-Bit DACs
REV. A
AD7397ARUZ AD-AD7397ARUZ Datasheet
216Kb / 12P
   3 V, Parallel Input Dual 12-Bit /10-Bit DACs
REV. 0
AD7396 AD-AD7396_15 Datasheet
229Kb / 12P
   3 V, Parallel Input Dual 12-Bit /10-Bit DACs
REV. 0
AD7397 AD-AD7397_15 Datasheet
229Kb / 12P
   3 V, Parallel Input Dual 12-Bit /10-Bit DACs
REV. 0
AD7396 AD-AD7396 Datasheet
226Kb / 12P
   3 V, Parallel Input Dual 12-Bit /10-Bit DACs
REV. 0
AD7391 AD-AD7391 Datasheet
342Kb / 12P
   3 Volt Serial-Input Micropower 10-Bit & 12-Bit DACs
REV. 0
AD7398BRZ-REEL7 AD-AD7398BRZ-REEL7 Datasheet
416Kb / 24P
   Quad, Serial-Input 12-Bit/10-Bit DACs
REV. C
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12


Folha de dados Download

Go To PDF Page


Ligação URL




Privacy Policy
ALLDATASHEETPT.COM
ALLDATASHEET é útil para você?  [ DONATE ] 

Sobre Alldatasheet   |   Publicidade   |   Contato conosco   |   Privacy Policy   |   roca de Link   |   Lista de Fabricantes
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
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