SBAS872B
December 2020 – October 2022
ADC3681
,
ADC3682
,
ADC3683
PRODUCTION DATA
1
Features
2
Applications
3
Description
4
Revision History
5
Pin Configuration and Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Information
6.5
Electrical Characteristics - Power Consumption
6.6
Electrical Characteristics - DC Specifications
6.7
Electrical Characteristics - AC Specifications
6.8
Timing Requirements
6.9
Typical Characteristics - ADC3681
6.10
Typical Characteristics - ADC3682
6.11
Typical Characteristics - ADC3683
7
Parameter Measurement Information
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Analog Input
8.3.1.1
Analog Input Bandwidth
8.3.1.2
Analog Front End Design
8.3.1.2.1
Sampling Glitch Filter Design
8.3.1.2.2
Analog Input Termination and DC Bias
8.3.1.2.2.1
AC-Coupling
8.3.1.2.2.2
DC-Coupling
8.3.1.3
Auto-Zero Feature
8.3.2
Clock Input
8.3.2.1
Single Ended vs Differential Clock Input
8.3.2.2
Signal Acquisition Time Adjust
8.3.3
Voltage Reference
8.3.3.1
Internal voltage reference
8.3.3.2
External voltage reference (VREF)
8.3.3.3
External voltage reference with internal buffer (REFBUF)
8.3.4
Digital Down Converter
8.3.4.1
DDC MUX
8.3.4.2
Digital Filter Operation
8.3.4.3
FS/4 Mixing with Real Output
8.3.4.4
Numerically Controlled Oscillator (NCO) and Digital Mixer
8.3.4.5
Decimation Filter
8.3.4.6
SYNC
8.3.4.7
Output Formatting with Decimation
8.3.5
Digital Interface
8.3.5.1
Output Formatter
8.3.5.2
Output Scrambler
8.3.5.3
Output Bit Mapper
8.3.5.4
Output Interface/Mode Configuration
8.3.5.4.1
Configuration Example
8.3.5.5
Output Data Format
8.3.6
Test Pattern
8.4
Device Functional Modes
8.4.1
Normal Operation
8.4.2
Power Down Options
8.4.3
Digital Channel Averaging
8.5
Programming
8.5.1
Configuration using PINs only
8.5.2
Configuration using the SPI interface
8.5.2.1
Register Write
8.5.2.2
Register Read
8.6
Register Map
8.6.1
Detailed Register Description
9
Application Information Disclaimer
9.1
Typical Application
9.1.1
Design Requirements
9.1.2
Detailed Design Procedure
9.1.2.1
Input Signal Path
9.1.2.2
Sampling Clock
9.1.2.3
Voltage Reference
9.1.3
Application Curves
9.2
Initialization Set Up
9.2.1
Register Initialization During Operation
9.3
Power Supply Recommendations
9.4
Layout
9.4.1
Layout Guidelines
9.4.2
Layout Example
10
Device and Documentation Support
10.1
Receiving Notification of Documentation Updates
10.2
Support Resources
10.3
Trademarks
10.4
Electrostatic Discharge Caution
10.5
Glossary
11
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
RSB|40
MPQF185C
Thermal pad, mechanical data (Package|Pins)
RSB|40
QFND255H
Orderable Information
sbas872b_oa
sbas872b_pm
1
Features
Dual channel ADC
18-bit 10, 25, 65 MSPS ADC
Noise floor: -160 dBFS/Hz
Low power and optimized power scaling:
53 mW/ch (10 MSPS) to 94 mW/ch (65 MSPS)
Latency: 1-2 clock cycles
18-bit, no missing codes
INL/DNL: ±7/ ±0.7 LSB (typical)
Reference: external or internal
Input bandwidth: 900 MHz (3-dB)
Industrial temperature range: -40 to +105°C
On-chip digital filter (optional)
Decimation by 2, 4, 8, 16, 32
32-bit NCO
Serial LVDS digital interface (2-, 1- and 1/2-wire)
Small footprint: 40-QFN (5x5 mm) package
Spectral performance (f
IN
= 5 MHz):
SNR: 83.8 dBFS
SFDR: 89 dBc HD2, HD3
SFDR: 101 dBFS Worst spur
Spectral performance (f
IN
= 20 MHz):
SNR: 82.6 dBFS
SFDR: 85 dBc HD2, HD3
SFDR: 97 dBFS Worst spur