Kebar Any overlap in Q1 and Q2 conduction will result in large currents flowing through the power devices between the high and low voltage motor rails. The Input-Output Momentary Withstand Voltage is a dielectric voltage rating that should not be interpreted as an input-output continuous voltage rating. These dimensions are needed as a starting point for the equipment designer when determining the circuit insulation requirements. Temperature Figure 3 VOH vs.
|Published (Last):||15 May 2015|
|PDF File Size:||11.87 Mb|
|ePub File Size:||11.16 Mb|
|Price:||Free* [*Free Regsitration Required]|
Vudok Techniques to keep the LED in the daasheet state are discussed in the next two sections. The high operating voltage range of the output stage provides the drive voltages required by gate controlled devices. This capacitive coupling causes perturbations in the LED current during common mode transients and becomes the major source of CMR failures for a shielded optocoupler. Documents Flashcards Grammar checker. Lab 9 in this note. All other brand and product names may be trademarks of their respective companies.
HCNW Datasheet These dimensions are needed as a starting point for the equipment designer when determining the circuit insulation requirements.
Figure 33 is an alternative drive circuit which, like the recommended application circuit Figure 25does achieve ultra high CMR performance by shunting the LED in the off state. This results in lower peak currents more margin than predicted by this analysis.
Data subject to change. Contact your Avago Technologies sales representative or authorized distributor for information. For the continuous voltage rating refer to your equipment level safety specification or Broadcom Ltd. Pins 1 and 4 need to be connected to LED common. The LED is optically coupled to an integrated circuit with a power output stage. However, once mounted on a printed circuit board, minimum creepage and clearance requirements must be met as specified for individual equipment standards.
Dead time is the time period during which both the high and low side power transistors Q1 and Q2 in Figure 25 are off. Creepage and clearance distances will also change depending datasjeet factors such datashret pollution degree and insulation level. For creepage, the shortest distance path along the surface of a printed circuit board between the solder fillets of the input and output leads must be considered.
There are recommended techniques such as grooves and ribs which may be used on a printed circuit board to achieve desired creepage and clearances.
Option data sheets are available. Note that the propagation delays used to calculate PDD and dead time are taken at equal temperatures and test conditions since the optocouplers under consideration are typically mounted in datadheet proximity to each other and are switching identical IGBTs. Device considered a two-terminal device: Any overlap in Q1 and Q2 conduction will result in large currents flowing through the power devices between the high and low voltage motor rails.
To minimize dead time in a given design, the turn on of LED2 should be delayed relative to the turn daasheet of LED1 so that under worst-case conditions, transistor Q1 has just turned off when transistor Q2 turns on, as shown in Figure When negative gate drive is not used VEE in the previous equation is equal to zero volts. Minimum External Tracking L Creepage 7. However, this shield does not eliminate the capacitive coupling between the LED and optocoupler pins 5—8 as shown in Figure See Applications section for additional details on limiting IOH peak.
The Input-Output Momentary Withstand Voltage is a dielectric voltage rating that should not be interpreted as an input-output continuous voltage rating. Temperature Figure 3 VOH vs. Delaying hcnww LED signal by the maximum propagation delay difference ensures that the minimum dead time is zero, but it does not tell a designer what the maximum dead time will be.