Datasheet AD9627 (Analog Devices) - 5

AD9627 GENERAL DESCRIPTION
The AD9627 is a dual, 12-bit, 80 MSPS/105 MSPS/125 MSPS/ exceeds the programmable threshold, the coarse upper threshold 150 MSPS analog-to-digital converter (ADC). The AD9627 is indicator goes high. Because this threshold indicator has very designed to support communications applications where low low latency, the user can quickly turn down the system gain to cost, small size, and versatility are desired. avoid an overrange condition. The dual ADC core features a multistage, differential pipelined The second AGC-related function is the signal monitor. This block architecture with integrated output error correction logic. Each allows the user to monitor the composite magnitude of the ADC features wide bandwidth differential sample-and-hold incoming signal, which aids in setting the gain to optimize the analog input amplifiers supporting a variety of user-selectable dynamic range of the overall system. input ranges. An integrated voltage reference eases design consid- The ADC output data can be routed directly to the two external erations. A duty cycle stabilizer is provided to compensate for 12-bit output ports. These outputs can be set from 1.8 V to 3.3 V variations in the ADC clock duty cycle, allowing the converters CMOS or 1.8 V LVDS. to maintain excellent performance. Flexible power-down options allow significant power savings, The AD9627 has several functions that simplify the automatic when desired. gain control (AGC) function in the system receiver. The fast detect feature allows fast overrange detection by outputting four bits of Programming for setup and control is accomplished using a 3-bit input level information with very short latency. SPI-compatible serial interface. In addition, the programmable threshold detector allows moni- The AD9627 is available in a 64-lead LFCSP and is specified over toring of the incoming signal power, using the four fast detect the industrial temperature range of −40°C to +85°C. bits of the ADC with very low latency. If the input signal level Rev. B | Page 4 of 76 Document Outline Features Applications Functional Block Diagram Product Highlights Revision History General Description Specifications ADC DC Specifications—AD9627-80/AD9627-105 ADC DC Specifications—AD9627-125/AD9627-150 ADC AC Specifications—AD9627-80/AD9627-105 ADC AC Specifications—AD9627-125/AD9627-150 Digital Specifications Switching Specifications—AD9627-80/AD9627-105 Switching Specifications—AD9627-125/AD9627-150 Timing Specifications Timing Diagrams Absolute Maximum Ratings Thermal Characteristics ESD Caution Pin Configurations and Function Descriptions Equivalent Circuits Typical Performance Characteristics Theory of Operation ADC Architecture Analog Input Considerations Input Common Mode Differential Input Configurations Single-Ended Input Configuration Voltage Reference Internal Reference Connection External Reference Operation Clock Input Considerations Clock Input Options Input Clock Divider Clock Duty Cycle Jitter Considerations Power Dissipation and Standby Mode Digital Outputs Digital Output Enable Function (OEB) Timing Data Clock Output (DCO) ADC Overrange and Gain Control Fast Detect Overview ADC Fast Magnitude ADC Overrange (OR) Gain Switching Coarse Upper Threshold (C_UT) Fine Upper Threshold (F_UT) Fine Lower Threshold (F_LT) Increment Gain (IG) and Decrement Gain (DG) Signal Monitor Peak Detector Mode RMS/MS Magnitude Mode Threshold Crossing Mode Additional Control Bits Signal Monitor Enable Bit Complex Power Calculation Mode Enable Bit DC Correction DC Correction Bandwidth DC Correction Readback DC Correction Freeze DC Correction Enable Bits Signal Monitor SPORT Output SMI SCLK SMI SDFS SMI SDO Built-In Self-Test (BIST) and Output Test Built-In Self-Test (BIST) Output Test Modes Channel/Chip Synchronization Serial Port Interface (SPI) Configuration Using the SPI Hardware Interface Configuration Without the SPI SPI Accessible Features Memory Map Reading the Memory Map Register Table Open Locations Default Values Logic Levels Transfer Register Map Channel-Specific Registers Memory Map Register Table Memory Map Register Descriptions Sync Control (Register 0x100) Bit 7—Signal Monitor Sync Enable Bits[6:3]—Reserved Bit 2—Clock Divider Next Sync Only Bit 1—Clock Divider Sync Enable Bit 0—Master Sync Enable Fast Detect Control (Register 0x104) Bits[7:4]—Reserved Bits[3:1]—Fast Detect Mode Select Bit 0—Fast Detect Enable Coarse Upper Threshold (Register 0x105) Bits[7:3]—Reserved Bits[2:0]—Coarse Upper Threshold Fine Upper Threshold (Register 0x106 and Register 0x107) Register 0x106, Bits[7:0]—Fine Upper Threshold[7:0] Register 0x107, Bits[7:5]—Reserved Register 0x107, Bits[4:0]—Fine Upper Threshold[12:8] Fine Lower Threshold (Register 0x108 and Register 0x109) Register 0x108, Bits[7:0]—Fine Lower Threshold[7:0] Register 0x109, Bits[7:5]—Reserved Register 0x109, Bits[4:0]—Fine Lower Threshold[12:8] Increase Gain Dwell Time (Register 0x10A and Register 0x10B) Register 0x10A, Bits[7:0]—Increase Gain Dwell Time[7:0] Register 0x10B, Bits[7:0]—Increase Gain Dwell Time[15:8] Signal Monitor DC Correction Control (Register 0x10C) Bit 7—Reserved Bit 6—DC Correction Freeze Bits[5:2]—DC Correction Bandwidth Bit 1—DC Correction for Signal Path Enable Bit 0—DC Correction for Signal Monitor Enable Signal Monitor DC Value Channel A (Register 0x10D and Register 0x10E) Register 0x10D, Bits[7:0]—DC Value Channel A[7:0] Register 0x10E, Bits[7:6]—Reserved Register 0x10E, Bits[5:0]—DC Value Channel A[13:8] Signal Monitor DC Value Channel B (Register 0x10F and Register 0x110) Register 0x10F, Bits[7:0]—DC Value Channel B[7:0] Register 0x110, Bits[7:6]—Reserved Register 0x110, Bits[5:0]—DC Value Channel B[13:8] Signal Monitor SPORT Control (Register 0x111) Bit 7—Reserved Bit 6—RMS/MS Magnitude Output Enable Bit 5—Peak Detector Output Enable Bit 4—Threshold Crossing Output Enable Bits[3:2]—SPORT SMI SCLK Divide Bit 1— SPORT SMI SCLK Sleep Bit 0—Signal Monitor SPORT Output Enable Signal Monitor Control (Register 0x112) Bit 7—Complex Power Calculation Mode Enable Bits[6:4]—Reserved Bit 3—Signal Monitor RMS/MS Select Bits[2:1]—Signal Monitor Mode Bit 0—Signal Monitor Enable Signal Monitor Period (Register 0x113 to Register 0x115) Register 0x113, Bits[7:0]—Signal Monitor Period[7:0] Register 0x114, Bits[7:0]—Signal Monitor Period[15:8] Register 0x115, Bits[7:0]—Signal Monitor Period[23:16] Signal Monitor Result Channel A (Register 0x116 to Register 0x118) Register 0x116, Bits[7:0]—Signal Monitor Result Channel A[7:0] Register 0x117, Bits[7:0]—Signal Monitor Result Channel A[15:8] Register 0x118, Bits[7:4]—Reserved Register 0x118, Bits[3:0]—Signal Monitor Result Channel A[19:16] Signal Monitor Result Channel B (Register 0x119 to Register 0x11B) Register 0x119, Bits[7:0]— Signal Monitor Result Channel B[7:0] Register 0x11A, Bits[7:0]—Signal Monitor Result Channel B[15:8] Register 0x11B, Bits[7:4]—Reserved Register 0x11B, Bits[3:0]—Signal Monitor Result Channel B[19:16] Applications Information Design Guidelines Power and Ground Recommendations LVDS Operation Exposed Paddle Thermal Heat Slug Recommendations CML RBIAS Reference Decoupling SPI Port Evaluation Board Power Supplies Input Signals Output Signals Default Operation and Jumper Selection Settings POWER VIN CLOCK PDWN CSB SCLK/DFS SDIO/DCS Alternative Clock Configurations Alternative Analog Input Drive Configuration Schematics Evaluation Board Layouts Bill of Materials Outline Dimensions Ordering Guide