adc121c027cimkx National Semiconductor Corporation, adc121c027cimkx Datasheet
adc121c027cimkx
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adc121c027cimkx Summary of contents
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... For 8-bit ADCs see the ADC081C021 and ADC081C027. For 10-bit ADCs see the ADC101C021 and ADC101C027. Connection Diagrams I2C ® registered trademark of Phillips Corporation. © 2008 National Semiconductor Corporation Features ■ C-Compatible 2-wire Interface which supports standard (100kHz), fast (400kHz), and high speed (3.4MHz) modes ■ ...
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... Ordering Information Order Code ADC121C021CIMK ADC121C021CIMKX ADC121C027CIMK ADC121C027CIMKX Shipped with the ADC121C021. ADC121C021EB Block Diagram www.national.com Option Alert pin Alert pin TSOT-6 Tape-and-Reel Address pin Address pin TSOT-6 Tape-and-Reel Also compatible with the Evaluation Board ADC121C027 option. Please order samples. 2 Package ...
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Pin Descriptions Symbol Type V Supply A GND Ground V Analog Input IN ALERT Digital Output SCL Digital Input Digital SDA Input/Output Digital Input, ADDR three levels Package Pinouts V A ADC121C021 1 TSOT-6 ADC121C027 1 TSOT-6 Equivalent Circuit Power ...
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Absolute Maximum Ratings (Notes Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage Voltage on any Analog Input Pin to GND Voltage on any Digital ...
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Symbol Parameter SFDR Spurious-Free Dynamic Range Intermodulation Distortion, Second Order Terms (IMD ) 2 IMD Intermodulation Distortion, Third Order Terms (IMD ) 3 FPBW Full Power Bandwidth (−3dB) ANALOG INPUT CHARACTERISTICS V Input Range Leakage Current (Note ...
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Symbol Parameter POWER REQUIREMENTS Supply Voltage Minimum V A Supply Voltage Maximum Continuous Operation Mode -- 2-wire interface active. I Supply Current N P Power Consumption N Automatic Conversion Mode -- 2-wire interface stopped and quiet (SCL = SDA = ...
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A.C. and Timing Characteristics The following specifications apply for 25°C, unless otherwise specified. A Symbol Parameter CONVERSION RATE Conversion Time f Conversion Rate CONV DIGITAL TIMING SPECS (SCL, SDA) f Serial Clock Frequency SCL t SCL Low ...
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Symbol Parameter t Rise time of SDA signal rDA t Fall time of SDA signal fDA t Rise time of SCL signal rCL Rise time of SCL signal after a t repeated start condition and after an rCL1 acknowledge bit. ...
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Note 7: The inputs are protected as shown below. Input voltage magnitudes up to 5.5V, regardless of V example 3V, the digital input pins can be driven with a 5V logic device. A Note 8: To guarantee ...
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Specification Definitions ACQUISITION TIME is the time required for the ADC to ac- quire the input voltage. During this time, the hold capacitor is charged by the input voltage. APERTURE DELAY is the time between the start of a con- ...
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Typical Performance Characteristics +25°C, unless otherwise stated. INL vs. Code - V A INL vs. Code - V A INL vs. Supply f = 400kHz, f SCL =3V 30020922 =5V 30020924 30020926 11 = 22kSPS 1kHz ...
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ENOB vs. Supply FFT Plot Offset Error vs. Temperature www.national.com SINAD vs. Supply 30020928 30020930 Gain Error vs. Temperature 30020932 12 30020929 FFT Plot 30020931 30020933 ...
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Continuous Operation Supply Current vs. V Power Down (PD ) Supply Current vs Automatic Conversion Supply Current vs 30020934 A 30020936 13 A 30020935 www.national.com ...
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Functional Description The ADC121C021 is a successive-approximation analog-to- digital converter designed around a charge-redistribution dig- ital-to-analog converter. Unless otherwise stated, references to the ADC121C021 in this section will apply to both the ADC121C021 and the ADC121C027. 1.1 CONVERTER OPERATION ...
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ADC TRANSFER FUNCTION The output format of the ADC121C021 is straight binary. Code transitions occur midway between successive integer LSB values. The LSB width for the ADC121C021 is V The ideal transfer characteristic is shown in Figure 5. The ...
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INTERNAL REGISTERS The ADC121C021 is equipped with 8 internal data registers and one address pointer register. The registers provide addi- tional ADC functions such as storing minimum and maximum conversion results, setting alert threshold levels, and storing data to ...
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Conversion Result Register Pointer Address 00h (Read Only) Default Value: 0000h D15 D14 D13 Alert Flag Reserved Bits Name Description 15 Alert Flag When the Alert Bit Enable is set in the Configuration Register, this bit ...
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Configuration Register Pointer Address 02h (Read/Write) Default Value: 00h Cycle Time [2:0] Alert Alert Hold Flag Enable Bits Name Description 7:5 Cycle Time Configures Automatic Conversion mode. When these bits are set to zeros, ...
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V -- Alert Limit Register - Under Range LOW Pointer Address 03h (Read/Write) Default Value: 0000h D15 D14 D13 Reserved Bits Name Description 15:12 Reserved Always reads zeros. Zeros must be written to these bits. 11:0 ...
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V -- Lowest Conversion Register MIN Pointer Address 06h (Read/Write) Default Value: 0FFFh D15 D14 Reserved D7 D6 Bits Name Description 15:12 Reserved Always reads zeros. Zeros must be written to these bits. 11:0 Lowest Conversion Contains the Lowest ...
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SERIAL INTERFACE The I 2 C-compatible interface operates in all three speed modes. Standard mode (100kHz) and Fast mode (400kHz) are functionally the same and will be referred to as Standard- Fast mode in this document. High-Speed mode (3.4MHz) ...
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Master sends a NACK to the ADC and generates a Stop condition to end communication after receiving 8-bits of data. For a 2-Byte read operation, the Master continues the transmission by sending an ACK to ...
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ALERT FUNCTION The ALERT function is an "out-of-range" indicator. At the end of every conversion, the measured voltage is compared to the values in the V and V registers. If the measured volt- HIGH LOW age exceeds the value ...
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COMMUNICATING WITH THE ADC121C021 The ADC121C021's data registers are selected by the ad- dress pointer (see Section 1.6.1). To read/write a specific data register, the pointer must be set to that register's address. The pointer is always written at ...
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Reading from a 1-Byte ADC Register FIGURE 13. (a) Typical Read from a 1-Byte ADC Register with Preset Pointer FIGURE 14. (b) Typical Pointer Set Followed by Immediate Read of a 1-Byte ADC Register 25 30020971 30020972 www.national.com ...
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Writing to an ADC Register FIGURE 16. (b) Typical Write to a 2-Byte ADC Register www.national.com FIGURE 15. (a) Typical Write to a 1-Byte ADC Register 26 30020964 30020973 ...
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QUIET INTERFACE MODE To improve performance at High Speed, operate the ADC in Quiet Interface Mode. This mode provides improved INL and DNL performance Hs-Mode (3.4MHz). The Quiet Inter- face mode provides a maximum throughput ...
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Applications Information 2.1 TYPICAL APPLICATION CIRCUIT A typical application circuit is shown in Figure 18. The analog supply is bypassed with a capacitor network located close to the ADC121C021. The ADC uses the analog supply (V its reference voltage, ...
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INTELLIGENT BATTERY MONITOR The ADC121C021 is easily used as an intelligent battery monitor. The simple circuit shown in Figure 20, uses the ADC121C021, the LP2980 fixed reference, and a resistor di- vider to implement an intelligent battery monitor with ...
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Physical Dimensions Order Numbers ADC121C021CIMK & ADC121C027CIMK www.national.com inches (millimeters) unless otherwise noted 6-Lead TSOT NS Package Number MK06A 30 ...
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Notes 31 www.national.com ...
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