Datasheet AD7699 (Analog Devices) - 9

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Data Sheet AD7699 AD7699 9 8 7 6 5 4 3 2 1 A IN3 IN2 IN0 VIO B VDD VDD IN1 SDO C REF REFIN DIN SCK D GND GND IN7 CNV E IN4 IN5 IN6 COM
100 07354- Figure 5. 20-Lead WLCSP Pin Configuration
Table 7. 20-Lead WLCSP Pin Function Descriptions Pin No. Mnemonic Type1 Description
B6, B8 VDD P Power Supply. Nominally 2.5 V to 5.5 V when using an external reference and decoupled with 10 μF and 100 nF capacitors. When using the internal reference for a 2.5 V output, the minimum must be 3.0 V. When using the internal reference for 4.096 V output, the minimum must be 4.6 V. C9 REF AI/O Reference Input/Output. See the Voltage Reference Output/Input section. When the internal reference is enabled, this pin produces a selectable system reference of 2.5 V or 4.096 V. When the internal reference is disabled and the buffer is enabled, REF produces a buffered version of the voltage present on the REFIN pin (VDD − 0.5 V, maximum), which is useful when using low cost, low power references. For improved drift performance, connect a precision reference to REF (0.5 V to VDD). For any reference method, this pin needs decoupling with an external 10 μF capacitor connected as close to REF as possible. See the Reference Decoupling section. C7 REFIN AI/O Internal Reference Output/Reference Buffer Input. See the Voltage Reference Output/Input section. When using the internal reference, the internal unbuffered reference voltage is present and requires decoupling with a 0.1 μF capacitor. When using the internal reference buffer, apply a source between 0.5 V and (VDD − 0.5 V) that is buffered to the REF pin, as described in the REF pin description. D6, D8 GND P Power Supply Ground. A7 IN3 AI Analog Input Channel 3. E5 IN5 AI Analog Input Channel 5. E3 IN6 AI Analog Input Channel 6 . D4 IN7 AI Analog Input Channel 7. E1 COM AI Common Channel Input. Al input channels, IN[7:0], can be referenced to a common-mode point of 0 V or VREF/2 V. D2 CNV DI Conversion Input. On the rising edge, CNV initiates the conversion. During conversion, if CNV is held low, the busy indictor is enabled. C5 DIN DI Data Input. Use this input for writing to the 14-bit configuration register. The configuration register can be written to during and after conversion. C3 SCK DI Serial Data Clock Input. This input is used to clock out the data on SDO and clock in data on DIN in an MSB first fashion. B2 SDO DO Serial Data Output. The conversion result is output on this pin, synchronized to SCK. In unipolar modes, conversion results are straight binary; in bipolar modes, conversion results are twos complement. A1 VIO P Input/Output Interface Digital Power. Nominal y at the same supply as the host interface (1.8 V, 2.5 V, 3 V, or 5 V). A3 IN0 AI Analog Input Channel 0. B4 IN1 AI Analog Input Channel 1. A5 IN2 AI Analog Input Channel 2. E7 IN4 AI Analog Input Channel 4 . 1 AI means analog input, AI/O means analog input/output, DI means digital input, DO means digital output, P means power, and NC means no internal connection. Rev. F | Page 9 of 32 Document Outline FEATURES APPLICATIONS FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY THEORY OF OPERATION OVERVIEW CONVERTER OPERATION TRANSFER FUNCTIONS TYPICAL CONNECTION DIAGRAMS Unipolar or Bipolar Bipolar Single Supply ANALOG INPUTS Input Structure Selectable Low-Pass Filter Input Configurations Sequencer Examples Source Resistance DRIVER AMPLIFIER CHOICE VOLTAGE REFERENCE OUTPUT/INPUT Internal Reference/Temperature Sensor External Reference and Internal Buffer External Reference Reference Decoupling POWER SUPPLY SUPPLYING THE ADC FROM THE REFERENCE DIGITAL INTERFACE READING/WRITING DURING CONVERSION, FAST HOSTS READING/WRITING DURING ACQUISITION, ANY SPEED HOSTS READING/WRITING SPANNING CONVERSION, ANY SPEED HOST CONFIGURATION REGISTER, CFG GENERAL TIMING WITHOUT A BUSY INDICATOR GENERAL TIMING WITH A BUSY INDICATOR READ/WRITE SPANNING CONVERSION WITHOUT A BUSY INDICATOR READ/WRITE SPANNING CONVERSION WITH A BUSY INDICATOR CHANNEL SEQUENCER Examples APPLICATION HINTS LAYOUT EVALUATING AD7699 PERFORMANCE OUTLINE DIMENSIONS ORDERING GUIDE