sx8725 Semtech Corporation, sx8725 Datasheet - Page 2

• Manufacturer Part Number: sx8725
• Description: Sx8725 Zoomingadc? For Pressure And Temperature Sensing
• Manufacturer: Semtech Corporation

ADVANCED COMMUNICATIONS & SENSING
Description..............................................................................................................................................................1
Applications............................................................................................................................................................1
Features ..................................................................................................................................................................1
Ordering Information .............................................................................................................................................1
Functional Block Diagram.....................................................................................................................................1
Absolute Maximum Ratings ..................................................................................................................................4
Electrical Characteristics ......................................................................................................................................5
ZoomingADC Specifications.................................................................................................................................6
Timing Characteristics ..........................................................................................................................................8
I
Pin Configuration ...................................................................................................................................................9
Marking Information...............................................................................................................................................9
Pin Description .......................................................................................................................................................9
Circuit Description ...............................................................................................................................................10
General Description .............................................................................................................................................. 10
Block Diagram ....................................................................................................................................................... 10
VREF ..................................................................................................................................................................... 10
GPIO ..................................................................................................................................................................... 11
Charge Pump ........................................................................................................................................................ 12
RC Oscillator ......................................................................................................................................................... 13
I
I
I
ZoomingADC ........................................................................................................................................................15
Features ................................................................................................................................................................ 15
Overview ............................................................................................................................................................... 15
ZADC Description.................................................................................................................................................. 15
Acquisition Chain................................................................................................................................................... 15
Registers ............................................................................................................................................................... 17
ZADC Detailed Functionality Description .............................................................................................................. 18
Continuous-Time vs. On-Request......................................................................................................................... 18
Input Multiplexers .................................................................................................................................................. 19
Programmable Gain Amplifiers ............................................................................................................................. 20
PGA & ADC Enabling............................................................................................................................................ 21
PGA1 ..................................................................................................................................................................... 21
PGA2 ..................................................................................................................................................................... 21
PGA3 ..................................................................................................................................................................... 21
ADC Characteristics .............................................................................................................................................. 22
Conversion Sequence ........................................................................................................................................... 22
Over-Sampling Frequency .................................................................................................................................... 22
Over-Sampling Ratio ............................................................................................................................................. 23
Elementary Conversions ....................................................................................................................................... 23
Resolution ............................................................................................................................................................. 24
Conversion Time and Throughput......................................................................................................................... 25
Output Code Format ............................................................................................................................................. 26
Power Saving Modes ............................................................................................................................................ 27
Registers Map ....................................................................................................................................................... 28
Registers Descriptions .......................................................................................................................................... 28
RC Register........................................................................................................................................................... 28
GPIO Registers ..................................................................................................................................................... 29
ZADC Registers .................................................................................................................................................... 30
Mode Register ....................................................................................................................................................... 31
Optional Operating Modes: External Voltage Reference Option .......................................................................... 32
Application Hints..................................................................................................................................................33
Recommended Operation Mode and Registers Settings...................................................................................... 33
Operation Mode..................................................................................................................................................... 33
V1.5 © 2007 Semtech Corp.
2
2
2
2
C Timing Waveforms ...........................................................................................................................................8
C.......................................................................................................................................................................... 14
C Communication Format ................................................................................................................................... 14
C Address ........................................................................................................................................................... 14
ZoomingADC™ for Pressure and Temperature Sensing
Table of Contents
2
www.semtech.com
SX8725