LTC2433-1IMS#TRPBF Linear Technology, LTC2433-1IMS#TRPBF Datasheet
LTC2433-1IMS#TRPBF
Specifications of LTC2433-1IMS#TRPBF
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LTC2433-1IMS#TRPBF Summary of contents
Page 1
... It provides 0.12LSB INL and 1.45 V RMS noise independent of V technology and provides single conversion settling of the digital filter. Through a single pin, the LTC2433-1 can be REF configured for better than 87dB input differential mode rejection at 50Hz and 60Hz 2 can be driven by an external oscillator for a user defined rejection frequency ...
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... Reference Input Voltage to GND .................................... – 0. Digital Input Voltage to GND ........ – 0. Digital Output Voltage to GND ..... – 0. Operating Temperature Range LTC2433-1C ............................................ LTC2433-1I ........................................ – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER CONDITIONS Resolution (No Missing Codes) 0 ...
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... C. (Note 3) A CONDITIONS + Voltage – Voltage + Voltage – Voltage + 5V GND CC – 5V 5. 5V, REF = 5.5V CC – 5V, REF = GND CC LTC2433-1 MIN TYP MAX UNITS 130 140 dB 140 130 140 dB 120 dB 120 dB MIN TYP MAX UNITS GND – GND – – ...
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... LTC2433 DIGITAL I PUTS A D DIGITAL OUTPUTS operating temperature range, otherwise specifications are at T SYMBOL PARAMETER V High Level Input Voltage IH CS Low Level Input Voltage IL CS High Level Input Voltage IH SCK V Low Level Input Voltage IL SCK I Digital Input Current IN CS Digital Input Current ...
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... Note 13: Guaranteed by design and test correlation. Note 14: The low sleep mode current is valid only when CS is high. Note 15: These parameters are guaranteed by design over the full = 139,800Hz 2% supply and temperature range. Automated testing procedures are limited by the LSB step size (V LTC2433-1 MIN TYP MAX UNITS 2.56 2000 0 ...
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... LTC2433 CTIO S V (Pin 1): Positive Supply Voltage. Bypass to GND with tantalum capacitor in parallel with 0.1 F ceramic capacitor as close to the part as possible. + – REF (Pin 2), REF (Pin 3): Differential Reference Input. The voltage on these pins can have any value between GND and V as long as the reference positive input, REF ...
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... IN – – IN DAC + REF – REF TEST CIRCUITS SDO 1.69k Hi Hi ADC Figure 1. Functional Block Diagram C = 20pF LOAD 24361 TA03 LTC2433-1 INTERNAL OSCILLATOR AUTOCALIBRATION F O AND CONTROL (INT/EXT) SDO SERIAL SCK INTERFACE CS DECIMATING FIR 24331 1.69k SDO C = 20pF LOAD Hi Hi-Z ...
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... ADC or when CS is brought HIGH. The device automatically initiates a new conversion and the cycle repeats. In order to maintain compatibility with 24-/32-bit data transfers possible to clock the LTC2433-1 with additional serial clock pulses. This results in additional data bits which are logic HIGH. ...
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... Output Data Format The LTC2433-1 serial output data stream is 19 bits long. The first 3 bits represent status information indicating the conversion state and sign. The next 16 bits are the conver- sion result, MSB first. The third and fourth bit together are also used to indicate an underrange condition (the differ- ential input voltage is below – ...
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... If both Bit 16 and Bit 15 are HIGH, the differential input voltage is above +FS. If both Bit 16 and Bit 15 are LOW, the differential input voltage is below –FS. The function of these bits is summarized in Table 1. Table 1. LTC2433-1 Status Bits Bit 18 Bit 17 Bit 16 Bit 15 Input Range EOC V 0.5 • ...
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... GND. O When a fundamental rejection frequency different from the range 49Hz to 61.2Hz is required or when the converter must be sychronized with an outside source, the LTC2433-1 can operate with an external conversion clock. The conveter automatically detects the presence of an external clock signal at the F pin and turns off the internal oscillator ...
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... Each bit of data is shifted out the SDO pin on the falling edge of the serial clock. In the Internal SCK mode of operation, the SCK pin is an output and the LTC2433-1 creates its own serial clock by Table 3. LTC2433-1 State Duration State ...
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... APPLICATIO S I FOR ATIO In addition, the CS signal can be used to trigger a new conversion cycle before the entire serial data transfer has been completed. The LTC2433-1 will abort any serial data transfer in progress and start a new conversion cycle anytime a LOW-to-HIGH transition is detected at the CS pin after the converter has entered the data output state (i ...
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... SCK, see Figure 7. On the rising edge of CS, the device aborts the data output state and imme- diately initiates a new conversion. This is useful for abort- ing an invalid conversion cycle or synchronizing the start of a conversion. 2. LTC2433 REFERENCE REF SCK VOLTAGE 3 – REF 0. ...
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... IN SDO –0.5V TO 0.5V REF REF 5 7 – GND BIT 18 BIT 17 BIT 16 BIT 15 BIT 14 BIT 13 EOC “O” SIG MSB DATA OUTPUT LTC2433-1 = EXTERNAL CLOCK SOURCE = INTERNAL OSC/SIMULTANEOUS 50Hz/60Hz REJECTION 3-WIRE SPI INTERFACE BIT 2 BIT 1 BIT 0 LSB CONVERSION 24331 F08 24331fa 15 ...
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... CS. This can be avoided by adding an external 10k pull-up resistor to the SCK pin or by never pulling CS HIGH when SCK is LOW. Whenever SCK is LOW, the LTC2433-1’s internal pull-up at pin SCK is disabled. Normally, SCK is not externally driven if the device is in the internal SCK timing mode. ...
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... POR cycle; therefore, the internal serial clock timing mode is automatically selected if SCK is not externally driven LOW (if SCK is loaded such that the internal pull-up cannot pull the pin HIGH, the external SCK mode will be selected). LTC2433 EXTERNAL CLOCK SOURCE 10 ...
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... SIG MSB DATA OUTPUT Figure 11. Internal Serial Clock, Continuous Operation Digital Signal Levels The LTC2433-1’s digital interface is easy to use. Its digital inputs (F O accept standard TTL/CMOS logic levels and the internal hysteresis receivers can tolerate edge rates as slow as 100 s. However, some considerations are required to take advantage of the exceptional accuracy and low supply current of this converter ...
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... F the differential input and reference connections. Driving the Input and Reference The input and reference pins of the LTC2433-1 converter are directly connected to a network of sampling capaci- tors. Depending upon the relation between the differential input voltage and the differential reference voltage, these capacitors are switching between these four pins transfering small amounts of charge in the process ...
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... The effect of this input dynamic current can be analyzed using the test circuit of Figure 13. The C includes the LTC2433-1 pin capacitance (5pF typical) plus the capacitance of the test fixture used to obtain the results shown in Figures 14 and 15. A careful implementation can ...
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... Nevertheless, when small values of C are unavoidably present as parasitics IN of input multiplexers, wires, connectors or sensors, the LTC2433-1 can maintain its accuracy while operating with relative large values of source resistance as shown 10k 100k ...
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... A 15k source resistance will create a 0LSB typical and 1LSB maximum offset voltage. Reference Current In a similar fashion, the LTC2433-1 samples the differen- tial reference pins REF of charge to and from the external driving circuits thus producing a dynamic reference current. This current does not change the converter offset, but it may degrade the gain and INL performance ...
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... F19 + – or REF (Small C ) Figure 20. –FS Error 0.01 F REF 800 900 1000 24331 F21 + – and REF (Large C ) Figure 22. –FS Error vs R REF LTC2433-1 + – and REF pins and external capacitance + + REF = 5V – REF = GND + IN = 1.25V – 3.75V ...
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... When operated with an external conversion clock (F oscillator), the LTC2433-1 output data rate can be in- creased as desired. The duration of the conversion phase is 20510/f haves as if the internal oscillator is used with simultaneous 50Hz/60Hz ...
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... If small external input and/ EOSC or reference capacitors ( are used, the effect of IN REF the external source resistance upon the LTC2433-1 typical performance can be inferred from Figures 14, 15, 19 and 20 in which the horizontal axis is scaled by 139,800 ...
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... Reducing the reference voltage is func- tionally equivalent to amplifying the input signal, however no amplifier is required. The LTC2433-1 has LSB when used with a 5V reference, however the thermal noise of the inputs is 1.45 V and is independent of reference voltage. Thus ...
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... DETAIL “A” (1.93 .006) 0.254 (.010) 0 – 6 TYP 0.53 0.01 (.021 .006) DETAIL “A” SEATING PLANE 0.17 – 0.27 (.007 – .011) TYP LTC2433-1 0.497 0.076 (.0196 .003 REF 3.00 0.102 (.118 .004) NOTE 0.86 1.10 (.034) ( ...
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... Output Rate, 200 V Noise, 24.6 ENOBs www.linear.com 5V 0 REF 3 – REF LTC2433 – IN SCK 8 SDO GND 24331 F30 Noise P-P Noise, 2ppm INL, Pin Compatible with LTC2433-1 RMS Noise RMS Noise 2-Channel Ping-Pong RMS LT/TP 0104 1K REV A • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2003 24331fa ...