HumiTel MSD Control Software
HumiTel is a network client and server software for control of MSD. The software replace manual control of MSD where the MSD floor life is highly dependent upon individual operator rather than a systemic approach.
At the heart of the HumiTel™ Automated MSD Management System are a centralized data base and numerous clients distributed at strategic locations within a factory. Barcode label bearing unique ID is used to identify each reel and each tray of components within the factory. Each client location is comprised of two or more stations and each station has its own Relative Humidity and temperature readings. For example, a HumiTel™ client can be located next to a dry cabinet with two stations ‘DRYBOX_IN’ and ‘DRYBOX_OUT’. The DRYBOX_IN station has Relative Humidity of 5% and temperature of 23ºC. The DRYBOX_OUT station has Relative Humidity of 45% and temperature of 23ºC. When a reel of component is going to be placed inside the dry box, the operator just scan the barcode ID on the reel and select DRYBOX_IN as the station. Then the floor life this particular reel of component will be calculated based on the Relative Humidity and temperature reading of the DRYBOX_IN station (5% RH, 23ºC). When a reel of component is removed from the dry cabinet, the operator scan the barcode ID on the reel and select DRYBOX_OUT as the station. Then the floor life of this particular reel of component will be calculated based on the Relative Humidity and temperature reading of the DRYBOX_OUT station (45% RH, 23ºC). The operation is very simple and easy to understand and the operator do not need to calculate the number of hours that the reel of component is exposed to certain humidity and temperature.
Implement J-STD-033B.1 with Minimum Operator Training
MSD Floor Life Handling in HumiTel
MSD has five different levels from 1-5. The MSD is more sensitive to moisture as the Moisture Sensitive Level (MSL) is higher. For example, J-STD-033B (Table 5-1, J-STD-033B.1) specifies that MSL 3 component can be exposed to 60% RH at ≤ 30ºC for up to 168 hours and still deem safe to be subjected to reflow temperature without quality issue. However, the safe exposure time is reduced to 48 hours for MSL 5 component. The different in floor life between MSL 3 and MSL 5 component is based on material used by the manufacturer of the component.
Not only is the floor life dictated by the MSL of the component, the floor life is also dictated by the lead configuration, thickness of the component. Table 7-1 in J-STD-033B specifies 3 different thickness for each MSL which bring the total number of MSD floor life ‘profile’ to 15 which component thickness is taken into account.
The profile of component is set up based on a combination of part number (P/N) and supplier part number within the HumiTel™ software. This association of MSL floor life profile is done only once in the HumiTel™ software and the association are stored in the centralized data base. Additional profiles can be added by user to meet user’s specific requirement.
When a reel of component is received at the factory, the operator enters the part number of the incoming reel of components. The HumiTel™ software cross references out the correct the MSL for the reel of component from the data base. A unique barcode ID is then generated and assigned to the reel. The association of the unique barcode ID with Part Number and MSL is then completed and all the transaction in and out of the station is identified by the barcode ID. Additional information such as Lot Code, Date Code and Supplier Code can also be associated to the barcode ID for traceability purpose.
Precise Floor Life Calculation based on actual ambient RH and Temperature
The MSD floor life calculation in the HumiTel™ software is based on actual ambient relative humidity and temperature reading. This is done by using the HumiTel™ humidity sensor. The HumiTel™ sensor can be connected to the client PC using a standard USB cable or through wireless link. The wireless link enable user to put the sensor inside a dry box to get the actual humidity and temperature inside the dry box. The sensor is housed inside an Aluminum can to reduce the fluctuation in reading the relative humidity when the door of the dry box is opened and closed but still give an accurate average reading of the humidity inside the dry box.
J-STD-033B provides the MSD floor life derating table in Table 7-1. The derating table allows calculation of floor life at different ambient relative humidity and temperature. The ability to calculate MSD floor life based on actual ambient condition greatly improve the reliability of the calculation in comparison to manual operation. Manual calculation of MSD floor life typical does not take actual ambient condition into account. As a matter of fact, most manual MSD management routines are overly simplified so as not to over burden the operators who are using the component in normal production.