Electrical Characteristics V

The following specifications apply for the circuit shown in Figure 1, unless otherwise specified. Limits apply for T

25˚C. (Continued)

Note 12: All bumps have the same thermal resistance and contribute equally when used to lower thermal resistance. The LM4901IBL demo board (views featured

and aid in spreading heat due to power dissipation within the IC.

Equation 1 shown in the Application Information section. It may also be obtained from the power dissipation graphs.

Note 14: The Exposed-DAP of the LDA10B package should be electrically connected to GND or an electrically isolated copper area. the LM4901LD demo board

(views featured in the Application Information section) has the Exposed-DAP connected to GND with a PCB area of 86.7mils x 585mils (2.02mm x 14.86mm) on

the copper top layer and 550mils x 710mils (13.97mm x 18.03mm) on the copper bottom layer.

Note 15: The thermal performance of the LLP package (LM4901LD) when used with the exposed-DAP connected to a thermal plane is sufficient for driving 4

Ω

loads. The LM4901LD demo board (views featured in the Application Information section) can drive 4

Ω loads at the maximum power dissipation point (1.267W)

without thermal shutdown circuitry being activated. The other available packages (MSOP & micro SMD) do not have the thermal performance necessary for driving

4

Ω loads with a 5V supply and are not recommended for this application.

External Components Description

(Figure 1)

Components

Functional Description

1.

R

i

Inverting input resistance which sets the closed-loop gain in conjunction with R

high pass filter with C

π R

2.

C

i

Input coupling capacitor which blocks the DC voltage at the amplifiers input terminals. Also creates a

highpass filter with R

π R

for an explanation of how to determine the value of C

3.

R

f

Feedback resistance which sets the closed-loop gain in conjunction with R

4.

C

S

Supply bypass capacitor which provides power supply filtering. Refer to the Power Supply Bypassing

section for information concerning proper placement and selection of the supply bypass capacitor.

5.

C

B

Bypass pin capacitor which provides half-supply filtering. Refer to the section, Proper Selection of External

Components, for information concerning proper placement and selection of C

Typical Performance Characteristics

THD+N vs Frequency

at V

Ω R

THD+N vs Frequency

at V

Ω R

20019830

20019831

www.national.com

5