Datasheet AD7476, AD7477, AD7478 (Analog Devices) - 10

AD7476/AD7477/AD7478 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS V 1 DD 6 CS AD7476/ AD7477/ GND 2 5 SDATA AD7478
3 00
V TOP VIEW
4-
3 IN 4 SCLK (Not to Scale)
02 01 Figure 3. Pin Configuration
Table 6. Pin Function Descriptions Pin No. Mnemonic Description
1 VDD Power Supply Input. The VDD range for the AD7476/AD7477/AD7478 is from 2.35 V to 5.25 V. 2 GND Analog Ground. Ground reference point for all circuitry on the part. All analog input signals should be referred to this GND voltage. 3 VIN Analog Input. Single-ended analog input channel. The input range is 0 V to VDD. 4 SCLK Serial Clock. Logic input. SCLK provides the serial clock for accessing data from the part. This clock input is also used as the clock source for the AD7476/AD7477/AD7478 conversion process. 5 SDATA Data Out. Logic output. The conversion result is provided on this output as a serial data stream. The bits are clocked out on the falling edge of the SCLK input. The data stream from the AD7476 consists of four leading zeros followed by the 12 bits of conversion data; this is provided MSB first. The data stream from the AD7477 consists of four leading zeros followed by the 10 bits of conversion data, followed by two trailing zeros, which is also provided MSB first. The data stream from the AD7478 consists of four leading zeros followed by the eight bits of conversion data, followed by four trailing zeros, which is provided MSB first. 6 CS Chip Select. Active low logic input. This input provides the dual function of initiating conversions on the AD7476/AD7477/AD7478 and framing the serial data transfer. Rev. F | Page 10 of 24 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM PRODUCT HIGHLIGHTS TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS AD7476 SPECIFICATIONS AD7477 SPECIFICATIONS AD7478 SPECIFICATIONS TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY THEORY OF OPERATION CIRCUIT INFORMATION CONVERTER OPERATION ADC TRANSFER FUNCTION TYPICAL CONNECTION DIAGRAM Analog Input Digital Input MODES OF OPERATION Normal Mode Power-Down Mode Power-Up Time POWER VS. THROUGHPUT RATE SERIAL INTERFACE MICROPROCESSOR INTERFACING AD7476/AD7477/AD7478 to TMS320C5x/C54x Interface AD7476/AD7477/AD7478 to ADSP-21xx Interface AD7476/AD7477/AD7478 to DSP56xxx Interface AD7476/AD7477/AD7478 to MC68HC16 Interface OUTLINE DIMENSIONS ORDERING GUIDE