LTC2408CG Linear Technology, LTC2408CG Datasheet
LTC2408CG
Specifications of LTC2408CG
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LTC2408CG Summary of contents
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... The LTC2404/LTC2408 communicate through a flexible 4-wire digital interface which is compatible with SPI and MICROWIRE , LTC and LT are registered trademarks of Linear Technology Corporation. No Latency MICROWIRE is a trademark of National Semiconductor Corporation. 0. 2.7V TO 5.5V ...
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... REF CC = 2.5V (Note 6) REF = 5V (Note 6) REF V REF CC V REF CC V REF CC V REF CC = 2.5V REF = 5V REF = 0V (Note 13) IN ORDER TOP VIEW PART NUMBER 28 GND 27 GND LTC2408CG LTC2408IG 25 SCK 24 SDO 23 CSADC 22 GND CSMUX 19 CLK 18 GND 17 CH7 16 GND 15 CH6 G PACKAGE = 125 C, = 130 C/W ...
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U CONVERTER CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER CONDITIONS Normal Mode Rejection 50Hz 2% (Note 8) Power Supply Rejection DC V Power Supply Rejection 60Hz 2% V Power Supply Rejection 50Hz ...
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LTC2404/LTC2408 U U 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 ...
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CHARACTERISTICS otherwise specifications are (Note 3) A SYMBOL PARAMETER f External Oscillator Frequency Range EOSC t External Oscillator High Period HEO t External Oscillator Low Period LEO t Conversion Time ...
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LTC2404/LTC2408 W U TYPICAL PERFOR A CE CHARACTERISTICS Total Unadjusted Error (3V Supply REF –55 C, – –5 –10 0 0.5 1.0 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS RMS Noise vs Reference Voltage REFERENCE VOLTAGE (V) 24048 G10 Noise Histogram 1500 V ...
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LTC2404/LTC2408 W U TYPICAL PERFOR A CE CHARACTERISTICS Conversion Current vs Temperature 230 220 V = 5.5V CC 210 V = 4.1V 200 CC 190 V = 2.7V CC 180 170 160 150 –50 – 100 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS INL vs Maximum Output Rate MAXIMUM OUTPUT ...
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LTC2404/LTC2408 PIN FUNCTIONS state aborts the data transfer and starts a new conversion. For normal operation, drive this pin in parallel with CSMUX. SDO (Pin 24): Three-State Digital Output. During the data output period this pin is ...
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U U APPLICATIONS INFORMATION Converter Operation Cycle The LTC2404/LTC2408 are low power, 4-/8-channel delta- sigma analog-to-digital converters with easy-to-use 4-wire interfaces. Their operation is simple and made up of four states. The converter operation begins with the conversion, followed by ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION Ease of Use The LTC2404/LTC2408 data output has no latency, filter settling or redundant data associated with the conversion cycle. There is a one-to-one correspondence between the conversion and the output data. Therefore, multiplexing an ...
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U U APPLICATIONS INFORMATION Bit 31 (first output bit) is the end of conversion (EOC) indicator. This bit is available at the SDO pin during the conversion and sleep states whenever the CSADC pin is LOW. This bit is HIGH ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION Channel Selection Typically, CSADC and CSMUX are tied together or CSADC is inverted and drives CSMUX. SCK and CLK are tied together and driven with a common clock signal. During channel selection, CSMUX is HIGH. ...
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U U APPLICATIONS INFORMATION The selection of 50Hz or 60Hz rejection can also be made by driving appropriate logic level. A selection O change during the sleep or data output states will not disturb the converter operation. ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION Using an External Clock for Faster Conversion Times The conversion time of the LTC2404/LTC2408 is deter- mined by the conditions on the GND for 60Hz rejection, the conversion time is 133 s. ...
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U U APPLICATIONS INFORMATION is used as an end of conversion indicator during the conversion and sleep states. When CSADC (Pin 23) is HIGH, the SDO driver is switched to a high impedance state. This allows sharing the serial interface ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION CSADC/ CSMUX SCK/CLK TEST EOC TEST EOC SDO Hi-Z Hi-Z D DON’T CARE While the device is in the sleep state, prior to entering the data output state, the user may ...
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U U APPLICATIONS INFORMATION CSADC/ CSMUX SCK/CLK BIT31 TEST EOC TEST EOC SDO Hi CONVERTER CONV SLEEP STATE Figure 8. Use of Look Ahead to Program Multiplexer After Data Output CSADC/ CSMUX SCK/CLK TEST EOC TEST EOC SDO ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION CSMUX t EOCtest CSADC SCKCLK TEST EOC TEST EOC SDO Hi-Z Hi-Z D DON’T CARE IN state. The internal serial clock (SCK) generated by the ADC is applied to the multiplexer clock input (CLK). In ...
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U U APPLICATIONS INFORMATION to the SCK pin. This signal may be used to shift the conversion result into external circuitry. EOC can be latched on the first rising edge of SCK and the last bit of the conversion result ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION mode. However, certain applications may require an exter- nal driver on SCK. If this driver goes Hi-Z after outputting a LOW signal, the LTC2404/LTC2408’s internal pull-up remains disabled. Hence, SCK remains LOW. On the next ...
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U U APPLICATIONS INFORMATION power dissipation. A series resistor between 27 and 56 placed near the driver or near the LTC2404/LTC2408 pin will also eliminate this problem without additional power dissipation. The actual resistor value depends upon the trace impedance ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION REF 0pF 100pF 1000pF ...
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U U APPLICATIONS INFORMATION Reference Current (V ) REF Similar to the analog input, the reference input has a dynamic input current. This current has negligible effect on the offset. However, the reference current similar to the ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION ANTIALIASING One of the advantages delta-sigma ADCs offer over con- ventional ADCs is on-chip digital filtering. Combined with a large oversampling ratio, the LTC2404/LTC2408 signifi- cantly simplify antialiasing filter requirements. The digital filter provides very ...
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U U APPLICATIONS INFORMATION + R1 20.1k 0. SEVERAL HUNDRED FEET. ALL SAME WIRE TYPE PT1 100 PLATINUM RTD PT2 TO PT3-PT6 PT7 Figure 24. Measuring Up to Seven RTD Temperatures with One Reference Resistor and One Reference ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION 10k 2 20k 10k 4 20k 10k 8 20k 10k 16 20k 10k 32 20k 10k 64 20k 10k 128 20k 10k Figure 25. Using the Multiplexer to Produce Programmable Gains 128 ...
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U U APPLICATIONS INFORMATION noise bandwidth of the system to 6Hz. The noise band- width of the LTC2408 without any input bandwidth lim- iting is approximately 150Hz. A roll-off at 1500Hz eliminates all higher order images of the base bandwidth ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION DIN1 EQU $00 This memory location holds the LTC2408’s bits DIN2 EQU $01 This memory location holds the LTC2408’s bits DIN3 EQU $02 This memory location holds the LTC2408’s ...
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U U APPLICATIONS INFORMATION * *************************************** * The SPI data transfer * *************************************** * TRFLP1 LDAA #$0 Load accumulator A with a null byte for SPI transfer STAA SPDR This writes the byte into the SPI data register and * ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION ***************************************************************************** * * This example program loads multiplexer channels selection data into * either the LTC2408’s internal MUX or an external LTC1391 MUX. It then * transfers the LTC2408’s 32-bit output conversion result to four ...
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U U APPLICATIONS INFORMATION ENLWMX TBA Restore contents of Accum. A ORAA #$08 Set the MUX’s ENABLE bit MUXSPI STAA SPDR Transfer Accum. A contents to SPI register to initiate * serial transfer WAITMUX LDAA SPSR Get SPI transfer status ...
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LTC2404/LTC2408 U U APPLICATIONS INFORMATION amplifier-based or self-contained instrumentation ampli- fiers (also available from LTC) can be used with the LTC2408. With the resistor network connected to CH0, the LTC2408 is able to measure DC voltages from 1mV to 1kV ...
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... FLASH SHALL NOT EXCEED 0.254mm (0.010") PER SIDE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... P–P 0.05% Max Initial Accuracy, 5ppm/ C Drift 10pA Max Input Bias Current, Low Voltage Noise: 8nV <4ppm INL, No Missing Codes, 4ppm Full Scale 1.2ppm Noise, 8ppm INL, Fast Mode 24048fa LT/LCG 0700 2K REV A • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1999 MPU ...