AS1542-BTSU ams, AS1542-BTSU Datasheet
AS1542-BTSU
Specifications of AS1542-BTSU
Related parts for AS1542-BTSU
AS1542-BTSU Summary of contents
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... MHz. The AS1542 features 16 single-ended or 8 fully differen- tial analog inputs with a channel sequencer to allow a programmed selection of channels to be converted sequentially. The conversion time is determined by the SCLK frequency (also used as the master clock to con- trol the conversion) ...
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... AS1542 Data Sheet 1 General Description ................................................................................................................................ 1 2 Key Features .......................................................................................................................................... 1 3 Applications ............................................................................................................................................ 1 4 Pinout ..................................................................................................................................................... 3 Pin Assignments ..................................................................................................................................................... 3 Pin Descriptions ..................................................................................................................................................... 3 5 Absolute Maximum Ratings .................................................................................................................... 4 6 Electrical Characteristics ........................................................................................................................ 5 Timing Specifications .............................................................................................................................................. 8 7 Typical Operating Characteristics ........................................................................................................... 9 8 Detailed Description ............................................................................................................................. 12 Converter Operation ............................................................................................................................................. 12 Analog Input ......................................................................................................................................................... 13 Track/Hold ..................................................................................................................................................... 13 Control Register ................................................................................................................................................... 14 Analog Input Configuration ............................................................................................................................ 15 Input Channel Selection ...
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... DOUT (MSB first). Output coding may be selected as straight binary or two’s complement depending on the setting of bit Digital Input. Data is clocked into to the AS1542 control register on this input DIN Register on page Chip Select. Active low input. Initiates conversions and also is used to frame the serial CSN data transfer ...
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... AS1542 Data Sheet - Absolute Maximum Ratings Stresses beyond those listed in Table 2 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 ...
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... AS1542 Data Sheet - Electrical Characteristics 2.7 to 5.25V, REFIN = 2.5V DRIVE T = -40 to +85°C. Typical values at T AMB Table 3. Electrical Characteristics Symbol Parameter DC Accuracy Resolution INL Integral Nonlinearity DNL ...
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... AS1542 Data Sheet - Table 3. Electrical Characteristics (Continued) Symbol Parameter Conversion Rate t Conversion Time CONV Track-and-Hold Acquisition Time Throughput Rate Aperture Delay Aperture Jitter Analog Input V Input Voltage Ranges INx ...
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... AS1542 Data Sheet - Table 3. Electrical Characteristics (Continued) Symbol Parameter Power Requirements V Input Supply Range DD V DRIVE Range DRIVE Input Current I DD Power Dissipation (see Power vs. Throughput Rate on page 23). ...
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... AS1542 Data Sheet - Timing Specifications ≤ 2.7 to 5.25V, VDRIVE V , REFIN = 2.5V based on load circuit shown in Figure 3 on page Table 4. Symbol Min Typ Max f 0.01 20 SCLK QUIET t 10 ...
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... AS1542 Data Sheet - Typical Operating Characteristics V = 5.25V 2.5V 4.7µF, RANGE=1, SE/FDN= REF REF Figure 5. Integral Nonlinearity vs. Digital Output Code 1 f SAMPLE 0,8 0,6 0,4 0,2 0 -0,2 -0,4 -0,6 -0 1024 2048 3072 Digital Output Code Figure 7. FFT @ 50kHz ...
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... AS1542 Data Sheet - Figure 11. THD vs. Input Signal Frequency -55 -60 VDD = 3.6V -65 VDD = 2.7V -70 VDD = 4.75V -75 -80 -85 VDD = 5.25V -90 10 100 Frequency (kHz) Figure 13. THD vs. Input Signal Frequency -60 -65 ...
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... AS1542 Data Sheet - Figure 15. Supply Current vs. Supply Voltage 3 f MAX 2.5 2 Static 1.5 1 2.7 3.2 3.7 4.2 Supply Voltage (V) Figure 17. Shutdown Supply Current vs 2.7 3.2 3.7 4.2 Supply Voltage (V) Figure 19. Supply Current vs. Throughput Rate ...
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... The AS1542 is a fast, 16-channel, 12-bit, single-supply, A/D converter, which can be operated from a 2.7 to 5.25V sup- ply. The AS1542 is capable of throughput rates 1Msps when provided with a 20MHz clock. The AS1542 fea- tures on-chip track/hold, A/D converter, sequencer and a serial interface in a TSSOP-28 package. ...
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... Care should be taken to ensure that the analog input signal never exceeds the supply rails by more than 300mV. This will cause these diodes to become forward biased and start conducting current into the substrate. 10mA is the maximum current these diodes can conduct without causing irreversible damage to the AS1542. Figure 23. Equivalent Analog Input Circuit ...
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... Data Sheet - Control Register The AS1542 control register is a 13-bit, write-only register. Data is loaded into the register from pin DIN on the falling edge of the SCLK signal. Data is transferred on pin DIN at the same time as the conversion result is read from the device ...
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... AS1542 Data Sheet - Analog Input Configuration Table 7. Analog Input Configuration via bits RANGE and SE/FDN Analog Input Configuration RANGE 16-channel single-ended 8-channel fully-differential Note: If bit RANGE = 0 and bit SE/FDN =1 V Input Channel Selection The input channels for conversion are selected using control register bits ADDR3:ADDR0 and bit SE/FDN ...
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... AS1542 Data Sheet - Transfer Functions Output coding and transfer function depend on the control register bits CODING (page 14). Figure 24. Straight Binary Transfer Function for SE/FDN = 1 and CODING = 1 RANGE = Full Scale REF REFIN RANGE = 0 ...
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... Control register bits PM1 and PM0 are used to configure the AS1542 power mode. Table 9. Power Mode Selection via Bits PM1 and PM0 PM1 PM0 Mode In this mode, the AS1542 remains in full power mode regardless of the status Normal Operation any of the logic inputs. This mode allows the fastest possible throughput rate. ...
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... Data Sheet - Shadow Register The shadow register is a 16-bit, write-only register. Data is loaded from pin DIN of the AS1542 on the falling edge of SCLK. The data is transferred on pin DIN at the same time as a conversion result is read from the device. This requires 16 serial falling edges for the data transfer ...
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... Data Sheet - Shadow Register Conversion (SEQ = 0, SHADOW = 1) Figure 29 shows how to program the AS1542 to continuously convert from a particular sequence of channels. To exit this mode of operation and revert back to the normal mode of operation of a multi-channel ADC (as outlined in Figure ...
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... Exit this flow whenever WRITE = 1 and NOT (SEQ = 1, SHADOW = 0) Serial Interface Figure 31 shows the detailed timing diagram for serial interfacing to the AS1542. The serial clock provides the conver- sion clock and also controls the transfer of information to and from the AS1542 during each conversion. Figure 31. Serial Interface Timing Diagram CSN t ...
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... If bit WEAK/TRIN is set to 0 and the DOUT signal has been in true tri-state between conversions, then depending on the particular DSP or microcontroller interfacing to the AS1542, address bit ADDR3 may not be set up in time for the DSP/micro to clock it in successfully. In this case, ADDR3 would only be driven from the falling edge of CSN and must then be clocked in by the DSP on the following falling edge of SCLK ...
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... PM1, PM0 (page 14) Note: When power supplies are first applied to the AS1542, internal power-on reset circuitry sets the device for Auto Shutdown (PM1 = 0, PM0 = x). The AS1542 remains in shutdown the first CSN falling edge is received. Normal Mode (PM1 = 1, PM0 = 1) This mode is intended for the fastest throughput rate performance as the user does not have to worry about any power-up times with the AS1542 remaining fully powered at all times ...
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... The Power vs. Throughput Rate graph in the Typical Operating Characteristics section shows how as the throughput rate is reduced, the part remains in its shutdown state longer and the average power consump- tion over time drops accordingly. If the AS1542 is operated in a continuous sampling mode with a throughput rate of 100ksps and a SCLK of 20 MHz (V = 5V), with bit PM1 (page 14 ...
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... V REFIN log Input Configuration on page 15). Errors in the reference source will result in gain errors in the AS1542 transfer function and will add to the specified full scale errors of the device. Note: A capacitor of at least 0.1µF should be placed on pin REFIN. ...
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... Data Sheet - Application Information Figure 35 shows a typical connection diagram for the AS1542. In this configuration, pin AGND, GND and DGND con- nected to the analog ground plane of the system. In source, to provide an analog input range 2.5V (if 5V (if bit RANGE is 0 and bit SE/FDN = 1) ...
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... Pins AGND and GND should be tied to the analog ground plane. Pin DGND should be tied to the digital ground plane. - Digital and analog ground planes should be joined at only one place. If the AS1542 system where multiple devices require an AGND-to-DGND connection, the connection should be made at one point – a star ground point which should be established as close as possible to the AS1542 ...
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... AS1542 Data Sheet - Package Drawings and Markings The device is available in an TSSOP-28 package. Figure 36. TSSOP-28 Package Symbol Min Nom Max A 1.10 A1 0.05 0.15 A2 0.85 0.90 0.95 L 0.50 0.60 0.75 R 0.09 R1 0.09 b 0.19 0.30 b1 0.19 0.22 0.25 c 0.09 0.20 c1 0.09 0.16 θ1 0º 8º ...
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... Data Sheet - Ordering Information The device is available as the standard products shown in Table 12. Ordering Information Model Marking AS1542-BTST AS1542 16-Channel, 1 Msps, 12-Bit ADC with Sequencer www.austriamicrosystems.com Table 12. Description Delivery Form Tape and Reel Revision 1 ...
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... AS1542 Data Sheet Copyrights Copyright © 1997-2007, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria-Europe. Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, trans- lated, 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. ...