My DRV134 PCB

[Algar_emi]

Since I completed my design, here for some that are interested, my own version of the DRV134 balanced driver PCB. It has these features: dual channels on one two layer PCB with ground plane, power and signal ground are connected at a star point, optional input resistor and low pass filter, +/- 15V supply with input CRC filter, optional external output sense pins. My first prototype has some errors in the power supply section. The following information has the correction implemented and it is working perfectly. Here a view of the PCB.

 

[Algar_emi]

Here the schematic. The current version 1.1 doesn't use D1-D2 diodes on the ground. Please install JP1 jumper and not the diodes if you do this PCB. The diodes were causing the DRV134 to have a 0.53V DC offset at the input and outputs pins.

 

[Algar_emi]

Here the parts list.

 

[Algar_emi]

Here the PCB in hires pdf format. For none commercial use only. This the parts location.

 

[Algar_emi]

The Top layer

 

[Algar_emi]

And the bottom layer.

 

[Algar_emi]

Final result.

 

[Algar_emi]

I tested the pcb today. Pretty impressive this DRV134 chip. Here my results, both left and right channel measured the same. All measurements were done driving a 1K load. The circuit is stable as a rock, no noise or oscillation.

Gain: 6.4dB
BW (1Khz, Ref 1V): 420Khz (My PCB has a 100R, 220pF cap LPF)
Dist 1Khz, 0dBV: 0.0003%, 10Khz: 0.002%
Dist IMD (1K, 2K): 0.005%
All harmonics are in the noise floor , lower than -90dB, ref 0dBV
DC offset (Input in 50R) (R & L Channel):
V+: 3.5mV, 0.3mV V-: -11.5mV, -13.5mV

Not bad at all.

 

[Steinberg]

Try to build the same. Thx

 

[Steinberg]

Are U sure that everything is ok with the schematic from (21st July 2007, 08:31 PM)???

Why Vin's of both channel are connected together via 2x100R & INPUT signals are going to Pin3 (GND) of both DRV134???


One more question:
what is the different between +Vo & +Sense (-Vo & -Sense)???
What is happen when use 'local sense jumper'???
I want to build then amp to drive balanced 'audio in' of camera.

thx, chris sng.pol46@gmail.com