News

  MSL stands for Moisture Sensitivity Level, which characterizes the ability of a chip to withstand humid environments. It is an extremely important parameter that is often overlooked by electronic engineers. Usually, chips exposed in an open environment will absorb moisture, which may enter the plastic packaging of the chip through the pins. During SMT reflow soldering, the moisture expands due to the instantaneous high temperature, and there is a probability of the so-called "POPCORN" phenomenon occurring. Classification of humidity sensitivity levels According to the JEDEC J-STD-020D standard, MSL is classified into 8 levels, as follows: MSL1 Level - Unlimited workshop life up to and including 30 ° C/85% RH MSL2 level - workshop lifespan of less than or equal to 30 ° C/60% RH for one year MSL2a level - workshop lifespan less than or equal to 30 ° C/60% RH for four weeks MSL3 level - workshop life less than or equal to 30 ° C/60% RH 168 hours MSL4 level - workshop life less than or equal to 30 ° C/60% RH 72 hours MSL5 level - workshop life less than or equal to 30 ° C/60% RH 48 hours MSL Level 5a - Workshop life of less than or equal to 30 ° C/60% RH for 24 hours MSL6 level - immediate workshop life less than or equal to 30 ° C/60% RH (for level 6, components must be baked before use and must be reflow soldered within the time limit specified on the moisture sensitive label) It is particularly important to note that if the ambient temperature or air humidity exceeds the limit test conditions for the corresponding level, the chip can be exposed to an open environment for a shorter period of time than the time specified in the standard. The impact of humidity sensitivity level and protective measures Once moisture enters the interior of the chip, there is a probability that sufficient steam pressure will be generated during SMT to damage or destroy the components. Common damage situations include internal separation (delamination) of the plastic body from the chip or pin frame, damage to the bonding wire soldering, chip damage, or cracks appearing inside the chip (which cannot be observed on the chip surface). The most serious situation is chip swelling and bursting (known as the "popcorn" effect). In addition, after moisture enters the interior of the chip, it may also cause electrochemical corrosion. Water vapor may be ionized to generate hydroxide ions when powered on, and the hydroxide ions may react chemically with the bonding pad or even the metal layer inside the chip, resulting in the formation of hydrated oxides. The oxides will also absorb some of the water vapor, creating fragile parts at the interface between the packaging resin and the metal, leading to bonding failure. If there are potassium, sodium, and chloride ions in the moisture, it will greatly increase the probability of corrosion of the chip, lead frame, and PAD, leading to delamination or peeling. After stratification occurs, the difficulty of moisture invasion is greatly reduced, and the reliability of the chip will also be greatly reduced.         Considering both cost and actual production process control, most chips will be packaged with MSL3 humidity sensitive grade and vacuum sealed bags, while desiccants and humidity sensitive cards will be placed inside. After unpacking the chip, it is necessary to complete the surface mounting and testing as soon as possible, and then apply coatings such as three proof paint for moisture sensitive protection. Once the vacuum bag leaks, the moisture sensitive card changes color, or the package is left for too long after unpacking, it is necessary to perform baking actions according to standard procedures before use to ensure the safety of chip use. Runshi Technology's automotive standard products Runshi Technology's automotive products all use MSL1 grade, and some industrial grade products also use MSL1 grade to better cope with the harsh operating or production environments of different product systems. Cost and quality are like the trade-off between fish and bear's paw. The higher the humidity sensitivity level, the higher the cost of packaging materials and processes, and the more expensive the chip price. Electronic engineers need to choose an acceptable cost, that is, the quality level of the chip, based on SMT production control capabilities, the working environment of the finished product, and market positioning when selecting.

12 bit low-power analog-to-digital conversion chip RS1320 RS1320 is a low-power single channel 12 bit analog-to-digital converter chip with a working voltage support of 2.7V to 5.5V. It supports SPI, QSPI, Microwire, and DSP interfaces, and can be used to achieve digital signal control output analog voltage, restore analog signals, or provide controllable reference voltage. It has a wide range of applications in industrial field data acquisition, various instrument measurement equipment, and analysis equipment. RS1320 is based on mainstream market products and optimized for key parameters according to user application needs, further reducing linear error, zero code error temperature drift, gain error, and gain error temperature drift. It also optimizes and improves conversion rate while considering low power consumption, shortening output voltage establishment time to meet more application scenarios. Its main parameter characteristics are as follows: Ø Ensure output monotonicity; Built in buffer, rail to rail voltage output; Ø Power on output zero voltage; Low power consumption: 1.17mW (3.6V)/2.94mW (5.5V); Ø INL: - 0.7LSB/+1.2LSB； Ø DNL: - 0.1LSB/+0.2LSB； Ø Zero code error 1.3mV; Ø Full scale error -0.01% FS; Ø Output voltage establishment time 6 μ s @ CL=500pF Ø Supports SPI data interface; Ø Extended industrial temperature range:- 40 ° C~125 ° C.   RS1320 adopts a resistor string architecture design, achieving excellent AC/DC characteristics. Some parameter curves are referenced as follows: For more detailed data and parameter curves, please refer to the specification sheet.   RS1320 packaging and pin definition RS1320 provides standard SOT23-6 packaging, with pin definitions fully compatible with DAC121S101. Engineers from all walks of life are welcome to taste and evaluate.