OPA445

SBOS156B − MARCH 1987 − REVISED APRIL 2008

www.ti.com

13

9.

With these preparatory steps in place, the PowerPAD

IC is simply placed in position and run through the

solder reflow operation as any standard surfacemount

component. This preparation results in a properly

installed part.

For detailed information on the PowerPAD package,

including thermal modeling considerations and repair

procedures, see technical brief SLMA002 PowerPAD

Thermally-Enhanced Package available for download at

www.ti.com.

OPTIONAL:

REQUIRED:

Thermal Land

(Copper)

Minimum S ize

4.8mm x 3.8mm

(189 mils x 150 mils)

Additional four vias outside

of thermal pad area but

under the package.

Thermal pad area 2.286mm x 2.286mm

(90 mils x 90 mils) with five vias

(via diameter = 13 mils)

Figure 14. 8-Pin PowerPAD PCB Etch and Via

Pattern

TYPICAL APPLICATIONS

OPA445

R

1

Compliance Voltage Range =

±35V

NOTE: R

+40V

100k

Ω

R

2

10k

Ω

R

3

100k

Ω

R

4

9.9k

Ω

−40V

R

5

100

Ω

I

L

Load

I

=(V

V

2

V

1

Figure 15. Voltage-to-Current Converter

OPA445

0−2mA

+60V

25k

Ω

−12V

V

at 10mA

0.1

µF

0.1

µF

Protects DAC

During Slewing

DAC8811

or

DAC7811

Figure 16. Programmable Voltage Source

+45V

160V

Crystal

−45V

Master

R

2

9k

Ω

R

1

1k

Ω

V

IN

±4V

OPA445

+45V

−45V

Slave

R

4

10k

Ω

R

3

10k

Ω

OPA445

NOTE: (1) For transducers with large capacitance the stabilization

technique described in Figure 6 may be necessary. Be certain that the

Master amplifier is stable before stabilizing the Slave amplifier.

Figure 17. Bridge Circuit Doubles Voltage for Piezo Crystals