foreword

The data manual in English can range from a dozen pages to hundreds of pages. When reading the data manual in English, it is impossible to cover everything. Of course, it is completely unnecessary. Learn to use Ctrl+F to search for keywords, and press Take whatever you want, just read the section we care about.

The following is an example of a DC-DC BUCK chip, which lists many keywords, and the same is true for other data sheets.

Title

The first is Title, which is also where manufacturers show their muscles. It will tell you some of the most important chip information, such as TPS56120x series, input voltage range 4.5~17V, maximum output current 1A, synchronous step-down, SOT-23 with 6Pin package, etc. .

Feature

If you are selecting a model and the above parameters meet the requirements, you will continue to look down. The feature shows more parameters, such as output voltage range, static power consumption, shutdown power consumption, accuracy and frequency.

Description

The description can give us a general understanding of this chip.

Table of Contents

Some data manuals will have a table of contents, you can first understand the general contents and help us find keywords.

Pin Configuration and Functions

You can understand the pin layout of the chip, the signal name corresponding to each pin, and you need to refer to the following figure when creating a schematic package.

Use pin functions to understand the functional description of each pin and what to pay attention to when designing the circuit.

Absolute Maximum

Absolute Maximum is the absolute maximum value. The parameters (voltage, temperature, ESD level, etc.) added to the chip must not exceed this value, otherwise the chip will be damaged.

Electrical Characteristics

The electrical parameters that hardware engineers must pay attention to, the electrical parameters of each chip are also different.

Typical Characteristics

Typical parameters refer to some chip characteristics measured by chip manufacturers under specific parameters, such as the relationship between different output voltages and switching frequencies below, the relationship between DC-DC efficiency and output current, etc. , this is to let us better understand the performance of the chip.

Functional Block Diagram

The functional block diagram is very important. By understanding the internal composition through the external pins, you can better understand the chip. For example, the SW pin is connected to two MOS tubes. Why is the duty cycle output? Both OVP and UVP are implemented by comparators and so on.

Feature Description

Describe some of the characteristics of the chip, let us better understand the relevant characteristics of this chip, the following DC-DC functions such as soft start, current protection, UVLO and other functions are described in detail.

Typical Application (typical application, that is, reference circuit diagram)

For chip data sheets, a typical application is the reference circuit diagram.

Layout Guide

For chip classes such as DC-DC, there is also a layout guide.

Packaging Information

The package information refers to the quantity in a box. As you can see below, the models of QTY3000 and QTY250 are different.

Different models of a series have different suffixes, which may be different packages, different package QTYs, etc., so you need to write the complete chip model when ordering.

Package Outline (package overview, that is, package size information)

Package size information, which will be used when creating a PCB package.

Example Layout

Build our own PCB package according to the reference layout provided.

Summarize

The list of so many keywords is not to teach you how to read the DC-DC data sheet, but to clarify a point: different people look at the data sheet with different focus, and hardware engineers pay more attention to electrical parameters, packaging information, For reference designs, etc., software engineers pay more attention to registers, protocols, etc., extracting keywords, reading data sheets efficiently, and finding content that is helpful to us is the most important.