전자부품 데이터시트 검색엔진 |
|
AD5233BRU100 데이터시트(PDF) 7 Page - Analog Devices |
|
AD5233BRU100 데이터시트(HTML) 7 Page - Analog Devices |
7 / 14 page PRELIMINARY TECHNICAL DATA Nonvolatile Memory Digital Potentiometers AD5231/AD5232/AD5233 REV PrF 7 22 MAR '01 Information contained in this Preliminary data sheet describes a product in the early definition stage. There is no guarantee that the information contained here will become a final product in its present form. For latest information contact Walt Heinzer/Analog Devices, Santa Clara, CA. TEL(408)382-3107; FAX (408)382-2708; walt.heinzer@analog.com OPERATIONAL OVERVIEW The AD5231/32/33 digital potentiometer family is designed to operate as a true variable resistor replacement device for analog signals that remain within the terminal voltage range of VSS<VTERM<VDD. The basic voltage range is limited to a |VDD - VSS| < 5.5V. Control of the digital potentiometer allows both scratch pad register (RDAC register) changes to be made, as well as, 100,000 nonvolatile electrically erasable memory (EEMEM) register operations. The EEMEM update process takes approximately 20.2ms, during this time the shift register is locked preventing any changes from taking place. The RDY pin flags the completion of this EEMEM save. The EEMEM retention is designed to last 15 years at 85°C, which is equivalent to 90 years at 55°C, without refresh. The scratch pad register can be changed incrementally by using the software controlled Increment/Decrement instruction or the Shift Left/Right instruction command. Once an Increment, Decrement or Shift command has been loaded into the shift register subsequent CS strobes will repeat this command. This is useful for push button control applications. Alternately the scratch pad register can be programmed with any position value using the standard SPI serial interface mode by loading the representative data word. The scratch pad register can be loaded with the current contents of the nonvolatile EEMEM register under program control. At system power ON, the default value of the scratch pad memory is the value previously saved in the EEMEM register. The factory EEMEM preset value is midscale. The scratch pad (wiper) register can be loaded with the current contents of the nonvolatile EEMEM register under hardware control by pulsing the PR pin. Beware that the PR pulse first sets the wiper at midscale when brought to logic zero, and then on the positive transition to logic high, it reloads the DAC wiper register with the contents of EEMEM. Similarly, the saved EEMEM value will automatically be retrieved to the scratch pad register during system power ON. A serial data output pin is available for daisy chaining and for readout of the internal register contents. The serial input data register uses a 16 or 24-bit instruction/address/data WORD. Write protect ( WP) disables any changes of current content in the scratch pad register regardless of the commands, except that EEMEM setting can be retrieved using commands 1 and 9. Therefore, write-protect ( WP) pin provides hardware EEMEM protection feature. DIGITAL INPUT/OUTPUT CONFIGURATION All digital inputs are ESD protected high input impedance that can be driven directly from most digital sources. For PR and WP, which are active at logic low, can be tied directly to VDD if they are not being used. The SDO and RDY pins are open drain digital outputs where pull-up resistors are needed only if using these functions. A resistor value in the range of 1k to 10k ohm optimizes the power and switching speed trade off. SERIAL DATA INTERFACE The AD523X family contains a four-wire SPI compatible digital interface (SDI, SDO, CS, and CLK). Key features of this interface include: • Independently Programmable Read & Write to all registers • Direct parallel refresh of all RDAC wiper registers from corresponding internal EEMEM registers • Increment & Decrement instructions for each RDAC wiper register • Left & right Bit Shift of all RDAC wiper registers to achieve 6dB level changes • Nonvolatile storage of the present scratch pad RDAC register values into the corresponding EEMEM register • Extra bytes of user addressable electrical-erasable memory The serial interface contains three different word formats to support the single AD5231, dual AD5232, and the quad AD5233 digital potentiometer devices. The AD5232 and AD5233 use a 16-bit serial data word loaded MSB first, while the AD5231 uses a 24-bit serial word loaded MSB first. The format of the SPI compatible word is shown in Table 1 and 2. The Command Bits (Cx) control the operation of the digital potentiometer according to the command instructions shown in Table 3, 4, and 5. The Address Bits (Ax) determine which register is activated. The Data Bits (Dx) are the values that are loaded into the decoded register. The last instruction executed prior to a period of no programming activity should be the No OPeration (NOP) instruction. This will place the internal logic circuitry in a minimum power dissipation state. SE R IA L RE G IS T E R CO UNT E R C O MMA ND PR O C ES SO R & AD D R ES S DE CO DE VA L ID C O MMA ND CS CL K SD I R PU LL U P +5 V SD O GN D PR Figure 2. Equivalent Digital Input-Output Logic The equivalent serial data input and output logic is shown in figure 2. The open drain output SDO is disabled whenever chip select CS is logic high. The SPI interface can be used in two slave modes CPHA=1, CPOL=1 and CPHA=0, CPOL=0. CPHA and CPOL refer to the control bits, which dictate SPI timing in the following microprocessors/Micro Converters: ADuC812/824, M68HC11, and MC68HC16R1/916R1. |
유사한 부품 번호 - AD5233BRU100 |
|
유사한 설명 - AD5233BRU100 |
|
|
링크 URL |
개인정보취급방침 |
ALLDATASHEET.CO.KR |
ALLDATASHEET 가 귀하에 도움이 되셨나요? [ DONATE ] |
Alldatasheet는? | 광고문의 | 운영자에게 연락하기 | 개인정보취급방침 | 링크교환 | 제조사별 검색 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 |