Datasheet

PGA870
www.ti.com SBOS436A –DECEMBER 2009–REVISED FEBRUARY 2011
PCB Layout Recommendations
Complete information about the PGA870EVM is found in the PGA870EVM User Guide, available for download
through the PGA870 product folder on the TI web site. Printed circuit board (PCB) layout should follow these
general guidelines:
1. Signal routing should be direct and as short as possible into and out of the device input and output pins.
Routing the signal path between layers using vias should be avoided if possible.
2. The device PowerPAD should be connected to a solid ground plane with multiple vias. The PowerPAD must
be connected to electrical ground. Consult the PGA870EVM User Guide for a layout example.
3. Ground or power planes should be removed from directly under the amplifier output pins.
4. A 0.1-μF capacitor should be placed between the V
MID
pin and ground near to the pin.
5. An output resistor is recommended in each output lead, placed as near to the output pins as possible.
6. Two 0.1-μF power-supply decoupling capacitors should be placed as near to the power-supply pins as
possible.
7. Two 10-μF power-supply decoupling capacitors should be placed within 1 in (2,54 cm) of the device.
8. The digital control pins use CMOS logic levels for high and low signals, but can tolerate being pulled high to
a +5-V power supply. The digital control pins do not have internal pull-up resistors.
© 2009–2011, Texas Instruments Incorporated 31
Product Folder Link(s): PGA870