AS1528-BTDR austriamicrosystems, AS1528-BTDR Datasheet

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... Automatic shutdown (0.2µA) between conversions results in reduced power consumption (at slower throughput rates). Data access are made via an external clock through the SPI-/QSPI-/MICROWIRE-compatible 3-wire high-speed serial interface. The AS1529/AS1528 are available in a 8-pin TDFN (3x3mm) package. Figure 1. AS1528/AS1529 - Block Diagram CNVST AIN1/AIN+ AIN2/AIN- www ...

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... Absolute Maximum Ratings ................................................................................................................. 4 6 Electrical Characteristics ...................................................................................................................... 5 Timing Characteristics ......................................................................................................................................... 7 7 Typical Operating Characteristics 8 Detailed Description ........................................................................................................................... 11 True Differential Analog Input Track/Hold Selecting AIN1 or AIN2 (AS1529) Selecting Unipolar or Bipolar Conversions (AS1528) Input Bandwidth ..................................................................................................................................................13 Analog Input Protection ......................................................................................................................................13 Internal Clock ......................................................................................................................................................13 Output Data Format ............................................................................................................................................13 Transfer Function ................................................................................................................................................13 9 Application Information ...

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... Positive Supply Voltage. +2.7V to +5.25V. Note: Bypass with a 0.1µF capacitor to GND. Analog Input Channel 1 (AS1529) or Positive Analog Input (AS1528) Analog Input Channel 2 (AS1529) or Negative Analog Input (AS1528) Ground External Reference Voltage Input. Sets the analog voltage range. Note: Bypass with a 4.7µF capacitor to GND. ...

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... AS1528/AS1529 Datasheet - Absolute Maximum Ratings Stresses beyond those listed in Table 3 and functional operation of the device at these or any other conditions beyond those indicated in istics on page 5 is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Table 3. Absolute Maximum Ratings ...

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... Input Leakage Current Input Capacitance External Reference Input V V Range REF IN I Input Current REF www.austriamicrosystems.com = 8MHz (50% Duty Cycle); AIN- = GND (AS1528) SCLK = +25ºC. Unipolar Mode (AS1528). AMB Condition No Missing Codes Over Temperature = 2.5V , 150ksps P-P SCLK -3dB Point -0.1dB Point ...

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... AS1528/AS1529 Datasheet - Table 4. Electrical Characteristics (Continued) Symbol Parameter Digital Inputs/Outputs (CNVST, SCLK, DOUT) V Input Low Voltage IL V Input High Voltage IH I Input Leakage Current LEAK C Input Capacitance IN V Output Low Voltage OL V Output High Voltage OH Tri-State Leakage Current Tri-State Output Capacitance ...

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... Figure 3. DOUT Enable/Disable Time Load Circuits DOUT 6kΩ GND High-impedance and Figure 4. Detailed Serial Interface Timing Diagram CNVST SCLK DOUT www.austriamicrosystems.com = 8MHz (50% Duty Cycle); AIN- = GND (AS1528) SCLK = +25ºC. AMB Conditions C = 30pF (see Figure 3, Figure LOAD Figure 18 on page 11, Figure 19 on page 11) ...

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... AS1528/AS1529 Datasheet - Typical Operating Characteristics 2.5V 8MHz(50% duty REF SCLK Figure 5. Integral Nonlinearity vs. Digital Output Code 0. 150ksps SAMPLE 0.2 0.15 0.1 0.05 0 -0.05 -0.1 -0.15 -0.2 -0.25 0 256 512 768 Digital Output Code Figure 7. Supply Current vs. Supply Voltage 600 500 ...

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... AS1528/AS1529 Datasheet - Figure 11. Shutdown Current vs. Supply Voltage 2.7 3.2 3.7 4.2 Supply Voltage (V) Figure 13. Offset Error vs. Supply Voltage 1 0.5 0 -0.5 -1 2.7 3.2 3.7 4.2 Supply Voltage (V) Figure 15. Gain Error vs. Supply Voltage 1 0.5 0 -0.5 -1 2.7 3.2 3.7 4.2 Supply Voltage (V) www.austriamicrosystems.com Figure 12. Shutdown Current vs. Temperature ...

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... DAC. The track/hold circuitry enters its tracking mode on the rising edge of CNVST. The positive input capacitor is connected to AIN1 or AIN2 (AS1529) or AIN+ (AS1528). The negative input capacitor is connected to GND (AS1529) or AIN- (AS1528). ...

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... AIN+ and AIN- connected to the input capacitors. Hold CNVST high for the signal. Drive CNVST low to place the track/hold circuitry in hold mode. The AS1528 then performs a conversion and shutdown automatically. The MSB is available at DOUT after 3.7µs. Data can then be clocked out using SCLK. ...

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... Note off-channel analog input voltage exceeds the supply voltages, the input current should be limited to 2mA. Internal Clock The AS1528/AS1529 operate from an internal clock, which is accurate within 5% of the 4MHz clock rate. This results in a worst-case conversion time of 3.7µs. The internal clock releases the system microprocessor from running the SAR conversion clock and allows the conversion results to be read back at the processor’ ...

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... AS1528/AS1529 Datasheet - Figure 21. AS1528 Bipolar Transfer Function Full Scale = V /2 REF -Full Scale = -V /2 REF Zero Scale = 0 1 LSB = V /4096 REF www.austriamicrosystems.com 011...111 011...110 000...010 000...001 000...000 111...111 111...110 111...101 100...001 100...000 ...

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... Standard Interface Connections The AS1528/AS1529 serial interface is fully compatible with SPI, QSPI, and MICROWIRE serial interface is avail- able, establish the processor’s serial interface as a master so that the CPU generates the serial clock for the AS1528/ AS1529 and select a clock frequency up to 8MHz. ...

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... Using the high-speed QSPI interface (Figure mum f of 8MHz. One 12- to 16-bit reads are necessary to obtain the entire 10-bit result from the AS1528/AS1529. SCLK DOUT data transitions on the serial clock’s falling edge and is clocked into the processor on SCLK’s rising edge. The first 10 bits are the data ...

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... MSB PIC16 and SSP Module and PIC17 Interface The AS1528/AS1529 are compatible with a PIC16/PIC17 controllers, using the synchronous serial port (SSP) module To establish SPI communication, connect the PIC16/PIC17 controllers as shown in PIC17 as system master. This is done by initializing its synchronous serial port control register (SSPCON) and syn- ...

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... Control Bit Setting WCOL Bit 7 X SSPOV Bit 6 X SSPEN Bit 5 1 CKP Bit 4 0 SSPM3:1 Bit 3:1 0 SSPM0 Bit 0 1 Table 7. SSPSTAT Register Settings AS1528/AS1529 Control Bit Setting SMP Bit 7 0 CKE Bit 6 1 D/A Bit Bit Bit 3 X R/W Bit 2 X ...

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... AS1528/AS1529 Datasheet - Layout and Grounding Considerations The AS1528/AS1529 require proper layout and design procedures for optimum performance. ! Use printed circuit boards; wirewrap boards should not be used. ! Separate analog and digital traces from each other. Analog and digital traces should not run parallel to each other (especially clock traces) ...

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... AS1528/AS1529 Datasheet - Package Drawings and Markings The devices are available in a 8-pin TDFN (3x3mm) package. Figure 30. 8-pin TDFN (3x3mm) Packagee D PIN 1 INDEX AREA aaa C 2x (D/2 xE/2) TOP VIEW e Terminal Tip DETAIL B e/2 Datum EVEN TERMINAL SIDE Symbol Min Typ A 0.70 ...

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... Ordering Information The devices are available as the standard products shown in Table 8. Ordering Information Ordering Code AS1528-BTDT 150ksps, 10-Bit, 1-Channel True-Differential ADC AS1528-BTDR 150ksps, 10-Bit, 1-Channel True-Differential ADC AS1529-BTDT 150ksps, 10-Bit, 2-Channel Single-Ended ADC AS1529-BTDR 150ksps, 10-Bit, 2-Channel Single-Ended ADC Note: All products are RoHS compliant and Pb-free. ...

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... AS1528/AS1529 Datasheet Copyrights Copyright © 1997-2009, austriamicrosystems AG, Tobelbaderstrasse 30, 8141 Unterpremstaetten, Austria-Europe. Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. All products and companies mentioned are trademarks or registered trademarks of their respective companies. ...