怎样阅读IC的数据手册

合集下载
相关主题
  1. 1、下载文档前请自行甄别文档内容的完整性,平台不提供额外的编辑、内容补充、找答案等附加服务。
  2. 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
  3. 3、如文档侵犯您的权益,请联系客服反馈,我们会尽快为您处理(人工客服工作时间:9:00-18:30)。

Specifications – Definitions
Many datasheets have a ‘Definitions’ or ‘Terminology’ section Most often found in specialized products


Otherwise, search the website glossary

Specifications
Details of the product performance All important, measureable parameters


Accuracy and speed Timing Power requirements

What the company guarantees


Power supplies Operating temperature -- usually 25C Input signal range Reference level, loading, gain setting, etc

Simple for op amps Complex for data converters and other products

Absolute Maximum Ratings Recommendations

What to do if it is certain part has exceeded Absolute Max – but still seems to work


Performance has been compromised in hidden ways Replace the part if you are making critical performance measurements Don’t send evaluation equipment with such parts to customers

Testing and specifications are driven by statistics

Typical Performance Curves (TPCs)

Typical performance curves show performance over the full operating range
All specifications have a distribution of values If it says typical, it’s not tested often


It was tested at release characterization Some units will be above, some below the spec Some distributions are loose, some tight Typical specs are screened by QA
Specifications -- Models

Models in a product family

Different specifications Different temperature ranges Different packages Different shipping packages (reel, tray, tube, etc)

If it says minimum or maximum, it may not be tested 100%

Specifications over temperature are guaranteed by characterization and guardbanding All tests have noise with Gaussian distribution Guardbands are set to keep failure in low ppm range

Spec differences will have separate columns
Test conditions – general and specific
General conditions at the top of specification page Apply to all specifications unless overridden in specific conditions of each spec

Product Selection


Owner’s manual


Choosing a product – the progression
General descriptions of product types Selection tables


Product features on product page Product features on product page
ILIM
50 74 114
100 92
150 100 150 300 500 900 1500 450 5
425
470
VINx Current Consumption Battery Current ConsumptionIQVIN IQVIN_DI源自 IQBATT2 280 20
mA µA µA µA mA

More likely to cover your operating range of interest Characterization of a large number of parts Often difficult to test by users Application may be non-standard, not at the center of specifications Datasheet authors attempt to anticipate most common use cases and operating conditions

Often an important part of product selection


Typical Performance Curves (TPCs)
Absolute Maximum Ratings
Section normally appears after Specifications Describes limits that will result in device damage Maximum voltages between pins Maximum currents into/out of pins Maximum temperatures for usage and storage Soldering and assembly conditions
0.5
0.9
Test conditions – Notes
Notes cited at bottom of page provide definitions, clarifications, and additional conditions The fine print

Minimum/maximum/typical

Test conditions – general and specific
Power supplies get very specific
Parameter Undervoltage lockout Hysteresis Total Input Current Symbol Min Typ Max Unit V mV mA Test Conditions/Comments Falling threshold, higher of VVIN and VBAT_SNS Hysteresis, higher of VVIN and VBAT_SNS rising1 Nominal USB initialized current level USB superspeed USB enumerated current level (specification for China) USB enumerated current level Dedicated charger input Dedicated wall charger Charging or LDO mode DIS_IC1 = high, VISO_B < VINx < 5.5 V LDO mode, VISO_S > VBAT_SNS Standby, includes ISO_Sx pin leakage, VVIN = 0 V, TJ = −40°C to +85°C Standby, battery monitor active

Purposes of a datasheet

Product description

Will this product fit my application Functions and specifications How do I get the functions to work How do I plug it in Complex products, such as DSP, often have separate manual on programming What else can the product do What new applications can I build What performance is guaranteed What voids the warranty
The World Leader in High Performance Signal Processing Solutions
WHAT’S IN A DATASHEET?
Presented by David Kress
Outline
Purposes of a datasheet What info do you need today? Product selection Specifications and conditions Absolute maximum ratings Thermal analysis Theory of operation and applications Packages and pinouts Ways to find what you are looking for What’s not in a datasheet

Test conditions – general and specific
Specific conditions shown at each spec line Describe conditions of testing and guarantees Typical performance charts show wider range of performance

Owner’s manual


Idea generator


Warranty document

What do I need today?

Idea generator

What else can the product do What new applications can I build Will this product fit my application Functions and specifications How do I get the functions to work How do I plug it in What else do I need Software Connecting products Documentation

Choosing a product – the progression
General specs and features look good Go to the datasheet Complete specs Detailed description Applications
相关文档
最新文档