IC测试原理解析
Page 30
Functional Test Concepts
Page 31
AC Tests
Page 32
AC Tests
Basic Terms * CODEC as example
1) Bits -- The number of unique codes produced by ADC output represented as a power of 2. 2) LSB -- Least Significant Bit, the amount of input voltage required to change the digital output by one code on an ideal ADC. 3) MSB -- Most Significant Bit, this is the digital output bit that carries the most weight. 4) Decibels -- a dimensionless unit of measurement of power ratio.
Page 2
接触测试图解
Page 3
第二节 漏电参数测试
IIL 是指当输入管脚置为逻辑0时的流过的电流大小,IIH是指当输入管脚置为 逻辑1时流过电流的大小。 IIL 实际测的是输入管脚到VDD之间的电阻,IIH实际测的是输入管脚到GND之 间的电阻 IIL测试方法: 1. VDDMAX 2.所有输入管脚预置逻辑1(VIH) 3. 通过PMU偏置每个管脚为逻辑0 (管脚与PE卡上的driver断开),通过PMU得到 实际电流的大小。 IIH测试方法: 1. VDDMAX 2.所有输入管脚预置逻辑0(VIL) 3. 通过PMU偏置每个管脚为逻辑1 (管脚与PE卡上的driver断开),通过PMU得到 实际电流的大小。
Page 28
Functional Test Concepts
Output Logic
Page 29
Functional Test Concepts
Basic Terms
1) VDD/GROUND 2) VIL/VIH 3) IIL/IIH 4) Clock Cycle 5) Test Pattern/Vector 6) Data Format 7) VOL/VOH 8) IOL/IOH (load) 9) Timing Strobe
第一章 数字集成电路测试原理
前言 器件测试的主要目的是保证器件在恶劣的环境条件下能完全实现设计规 格书所规定的功能及性能指标。用来完成这一功能的自动测试设备是由 计算机控制的。 因此,测试工程师必须对计算机科学编程和操作系统有 详细的认识。测试工程师必须清楚了解测试设备与器件之间的接口,懂 得怎样模拟器件将来的电操作环境,这样器件被测试的条件类似于将来 应用的环境。 首先有一点必须明确的是,测试成本是一个很重要的因素,关键目的之 一就是帮助降低器件的生产成本。甚至在优化的条件下,测试成本有时 能占到器件总体成本的40%左右。良品率和测试时间必须达到一个平衡, 以取得最好的成本效率。
Page 4
IIL参数测试图解
Page 5
IIH参数测试图解
Page 6
第三节 电源消耗参数测试(ICC,IDD)
COMS器件的电源消耗称为IDD,TTL器件的电源消耗称为ICC。 该项测试决定器件的电源消耗规格,也就是电源管脚在规定的电压条 件下的最大电流消耗。电源消耗测试可分为静态电源消耗测试和动态电源 消耗测试。静态电源消耗测试决定器件在空闲状态下时最大的电源消耗, 而动态电源消耗测试决定器件工作时的最大电源消耗。 静态测试方法: 1.一般使用DPS(有的机器可以使用PMU)偏置VDDMAX。 2.通过PATTERN 使IC预置初始(空闲)状态。 2.等待1-5 msec ,再通过DPS量测得到的电流。 3.与设计规格比较得出P/F的结果
Page 25
Functional Test Concepts
Defining the Operation of a DUT with a Truth Table
Page 26
Functional Test Concepts
Page 27
Functional Test Concepts
Input Logic
Test Method :
1) Power up DUT 2) Precondition DUT to either static mode or operating mode 3) Measure current of power supply
Page 19
Other DC Tests
Example 1:
Page 13
Leakage Tests
INPUT LEAKAGE TEST
To ensure high impedance is observed by the stimulus functional signals at the input pins.
Page 14
Leakage Tests
Reference Voltage test Internal or External Circuit to supply very accurate voltage as reference.
Test Method: 1) Power up DUT 2) Precondition DUT so that Vref can be accessed from PUT 3) Measure voltage from PUT
Page 15
Leakage Tests
OUTPUT LEAKAGE TEST
To ensure the Bi-directional and Output tri-state pins will not cause loading on user’s system application board.
Page 1
第一节 直流参数测试
接触测试(短路-开路):这项测试保证测试接口与器件正常连接。 接触测试通过测量输入输出管脚上保护二极管的自然压降来确定连接性。 二级管上如果施加一个适当的正向偏置电流,二级管的压降将是0.7V左 右,因此接触测试就可以由以下步骤来完成: 1.所有管脚设为0V, 2.待测管脚上施加正向偏置电流”I”, 3.测量由”I”引起的电压, 4.如果该电压小于0.1V,说明管脚短路, 5.如果电压大于1.0V,说明该管脚开路, 6.如果电压在0.1V和1.0V之间,说明该管脚正常连接
Page 16
Leakage Tests
OUTPUT LEAKAGE TEST
Test Method : 1) Power up DUT 2) Pre-condition DUT output pins to Hi-Z state 3) Force VDD at PUT and measure resultant current (IOZH) 4) Force GND at PUT and measure resultant current (IOZL)
Page 12
Continuity Test
1) Set VDD to 0V 2) Source/sink current, normally 100µA to 500µA with clamp voltage. Depends on ESD diode design. 3) Measure voltage output, suppose to be forward-biased diode voltage drop, around +/-0.7V
Page 10
DC / Parametric Tests
Page 11
Continuity Test
Purpose
To ensure there is proper and correct connection from device lead/ball to internal circuits To ensure there is proper and correct hardware setup condition prior to actual device testing
Page 21
Other DC Tests
PSRR Test Method:
1) supply VDD = A (V), measure VoutA(V) 2) supply VDD = B (V), measure VoutB e 22
Functional Tests
Page 24
Functional Test Concepts
All functional tests consist of two distinct components, 1. the test vector or pattern file 2. the instructions contained within the main test program. The test vector or pattern file represents the input and output logic states needed to test the DUT. The test program contains the information needed to control the test hardware in a manner that will create all the necessary voltages, waveforms and timings.
Page 23
Functional Test Concepts
What is Digital Functional Testing?
Digital Functional Testing is to: 1. Define input waveforms per DUT requirements; and 2. Check output waveforms against expected data of DUT Ensure DUT will correctly perform its intended logical function.