jimmyinct
Electrical
- Feb 14, 2009
- 12
Im working on building an ultrasound driver for a research.
I found one online that seems to be well documented. It is basically a class D audio amplifer. There are two figures given in this pdf below. Figure 1 is the main core of the circuit.
the el7158 pin driver datasheet is here
the irf 7350 matched pair mosfet chip is here
Ive tried building this a few times last week and kept blowing the pin drivers left and right without even adding the mosfet. The pin driver blew when the VH/VS went over 7 volts although it should run at 12V.
To simply, i ran the test circuit on the intersil datasheet with VS/VH(pin1 and 8) at 12V, pin2 (OE 12volt through 10k), and pins 4,5,6 grounded. The output is pin 7 has no load. I have as an input, pin 3, at 1.5hmtz, at 5 volts peak to peak.
Id like a 2nd opinon on this as Im not sure how i am screwing up. These chips are surface mounted and hard to work. I did call intersil tech support, they said it was because pin 6 VL was grounded and it was listed as output, but it seems to not work if i dont ground it. Im having a hard time getting a staright answer on this. I feel the intersil tech person was not knowledgable, as this should be a simple question, im just very rusty at power electronics.
does this circuit (figure 1) make sense?
1. for the pin driver, EL 7158, the low output (VL) is grounded?
2. for the mosfet(s), it looks as if the high voltage is connected to the souce rather than the drain. Is this correct? Dosent the high normally connect to the drain? Im not sure how its workign though.
3. the person who made it has individual capactiors at each mosfet at the 50V and -50 volts rails, a total of 8 times for each. Wouldnt these all just add up to one larger value?
I found one online that seems to be well documented. It is basically a class D audio amplifer. There are two figures given in this pdf below. Figure 1 is the main core of the circuit.
the el7158 pin driver datasheet is here
the irf 7350 matched pair mosfet chip is here
Ive tried building this a few times last week and kept blowing the pin drivers left and right without even adding the mosfet. The pin driver blew when the VH/VS went over 7 volts although it should run at 12V.
To simply, i ran the test circuit on the intersil datasheet with VS/VH(pin1 and 8) at 12V, pin2 (OE 12volt through 10k), and pins 4,5,6 grounded. The output is pin 7 has no load. I have as an input, pin 3, at 1.5hmtz, at 5 volts peak to peak.
Id like a 2nd opinon on this as Im not sure how i am screwing up. These chips are surface mounted and hard to work. I did call intersil tech support, they said it was because pin 6 VL was grounded and it was listed as output, but it seems to not work if i dont ground it. Im having a hard time getting a staright answer on this. I feel the intersil tech person was not knowledgable, as this should be a simple question, im just very rusty at power electronics.
does this circuit (figure 1) make sense?
1. for the pin driver, EL 7158, the low output (VL) is grounded?
2. for the mosfet(s), it looks as if the high voltage is connected to the souce rather than the drain. Is this correct? Dosent the high normally connect to the drain? Im not sure how its workign though.
3. the person who made it has individual capactiors at each mosfet at the 50V and -50 volts rails, a total of 8 times for each. Wouldnt these all just add up to one larger value?
