Electronic Components Datasheet Search |
|
AD7537AQ Datasheet(PDF) 4 Page - Analog Devices |
|
AD7537AQ Datasheet(HTML) 4 Page - Analog Devices |
4 / 8 page AD7537 REV. 0 –4– PIN FUNCTION DESCRIPTION (DIP) PIN MNEMONIC DESCRIPTION 1 AGNDA Analog Ground for DAC A. 2IOUTA Current output terminal of DAC A. 3RFBA Feedback resistor for DAC A. 4VREFA Reference input to DAC A. 5 CS Chip Select Input Active low. 6–14 DB0–DB7 Eight data inputs, DB0–DB7. 12 DGND Digital Ground. 15 A0 Address Line 0. 16 A1 Address Line 1. 17 CLR Clear Input. Active low. Clears all registers. 18 WR Write Input. Active low. 19 UPD Updates DAC Registers from inputs registers. 20 VDD Power supply input. Nominally +12 V to +15 V, with ±10% tolerance. 21 VREFB Reference input to DAC B. 22 RFBB Feedback resistor for DAC B. 23 IOUTB Current output terminal of DAC B. 24 AGNDB Analog Ground for DAC B. LCCC DIP PLCC PIN CONFIGURATIONS CIRCUIT INFORMATION – D/A SECTION The AD7537 contains two identical 12-bit multiplying D/A converters. Each DAC consists of a highly stable R-2R ladder and 12 N-channel current steering switches. Figure 2 shows a simplified D/A circuit for DAC A. In the R-2R ladder, binary weighted currents are steered between IOUTA and AGNDA. The current flowing in each ladder leg is constant, irrespective of switch state. The feedback resistor RFBA is used with an op amp (see Figures 4 and 5) to convert the current flowing in IOUTA to a voltage output. Figure 2. Simplified Circuit Diagram for DAC A EQUIVALENT CIRCUIT ANALYSIS Figure 3 shows the equivalent circuit for one of the D/A con- verters (DAC A) in the AD7537. A similar equivalent circuit can be drawn for DAC B. COUT is the output capacitance due to the N-channel switches and varies from about 50 pF to 150 pF with digital input code. The current source ILKG is composed of surface and junction leakages and approximately doubles every 10 °C. R 0 is the equivalent output resistance of the device which varies with input code. DIGITAL CIRCUIT INFORMATION The digital inputs are designed to be both TTL and 5 V CMOS compatible. All logic inputs are static protected MOS gates with typical input currents of less than 1 nA. Table I. AD7537 Truth Table CLR UPD CS WR A1 A0 FUNCTION 1 1 1 X X X No Data Transfer 1 1 X 1 X X No Data Transfer 0 X X X X X All Registers Cleared 1 1 0 0 0 0 DAC A LS Input Register Loaded with DB7–DB0 (LSB) 1 1 0 0 0 1 DAC A MS Input Register Loaded with DB3 (MSB)–DB0 1 1 0 0 1 0 DAC B LS Input Register Loaded with DB7–DB0 (LSB) 1 1 0 0 1 1 DAC B MS Input Register Loaded with DB3 (MSB)–DB0 1 0 1 0 X X DAC A, DAC B Registers Updated Simultaneously from Input Registers 1 0 0 0 X X DAC A, DAC B Registers are Transparent NOTES: X = Don’t care Figure 3. Equivalent Analog Circuit for DAC A |
Similar Part No. - AD7537AQ |
|
Similar Description - AD7537AQ |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List 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 |