Datasheet AD7989-1, AD7989-5 (Analog Devices) - 8

AD7989-1/AD7989-5 Data Sheet PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS REF 1 10 VIO VDD 2 AD7989-1/ 9 SDI/CS AD7989-5 IN+ 3 8 SCK TOP VIEW IN– 4 (Not to Scale) 7 SDO REF 1 10 VIO GND 5 6 CNV VDD 2 AD7989-1/ 9 SDI/CS AD7989-5 IN+ 3 8 SCK NOTES TOP VIEW IN– 1. EXPOSED PAD. FOR THE LFCSP, THE 4 7 SDO (Not to Scale)
004
EXPOSED PAD CAN BE CONNECTED TO GND.
005
GND 5 6 CNV THIS CONNECTION IS NOT REQUIRED TO MEET THE ELECTRICAL PERFORMANCES.
32- 10232- 102 Figure 4. 10-Lead MSOP Pin Configuration Figure 5. 10-Lead LFCSP Pin Configuration
Table 7. Pin Function Descriptions Pin No. Mnemonic Type1 Description
1 REF AI Reference Input Voltage. The REF range is 2.4 V to 5.1 V. This pin is referred to the GND pin and must be decoupled closely to the GND pin with a 10 μF capacitor. 2 VDD P Power Supply. 3 IN+ AI Differential Positive Analog Input. 4 IN− AI Differential Negative Analog Input. 5 GND P Power Supply Ground. 6 CNV DI Conversion Input. This input has multiple functions. On its leading edge, it initiates the conversions and selects the interface mode of the device: chain mode or chip select (CS) mode. In CS mode, the SDO pin is enabled when CNV is low. In chain mode, the data is read when CNV is high. 7 SDO DO Serial Data Output. The conversion result is output on this pin. It is synchronized to SCK. 8 SCK DI Serial Data Clock Input. When the device is selected, the conversion result is shifted out by this clock. 9 SDI/CS DI Serial Data Input/Chip Select. This input has multiple functions. It selects the interface mode of the ADC as follows: Chain mode is selected if this pin is low during the CNV rising edge. In this mode, SDI/CS is a data input that daisy-chains the conversion results of two or more ADCs onto a single SDO line. The digital data level on SDI/CS is the output on SDO with a delay of 16 SCK cycles. CS mode is selected if SDI/CS is high during the CNV rising edge. In this mode, either SDI/CS or CNV can enable the serial output signals when low. 10 VIO P Input/Output Interface Digital Power. This pin is nominally at the same supply as the host interface (1.8 V, 2.5 V, 3 V, or 5 V). EPAD Exposed Pad. For the LFCSP, the exposed pad can be connected to GND. This connection is not required to meet the electrical performances. 1AI means analog input, DI means digital input, DO means digital output, and P means power. Rev. B | Page 8 of 24 Document Outline Features Applications General Description Typical Applications Circuit Revision History Specifications Timing Specifications Absolute Maximum Ratings ESD Caution Pin Configurations and Function Descriptions Typical Performance Characteristics Terminology Theory of Operation Circuit Information Converter Operation Transfer Functions Typical Connection Diagram Analog Inputs Driver Amplifier Choice Single-Ended to Differential Driver Voltage Reference Input Power Supply Digital Interface CSB Mode, 3-Wire CSB Mode, 4-Wire Chain Mode Applications Information Interfacing to Blackfin® DSP Layout Evaluating AD7989-1/AD7989-5 Performance Outline Dimensions Ordering Guide