PAM8606 datasheet(14/16 Pages) PAM

14 / 16 page

-resistance (ESR) ceramic capacitor, typically

1μF, is recommended, placing as close as

possible to the device’s VCC lead. To filter lower-

frequency noises, a large aluminum electrolytic

capacitor of 10μF or greater is recommended,

placing near the audio power amplifier. The 10μF

capacitor also serves as a local storage capacitor

for s upplying current during large signal

transients on the amplifier outputs.

The switching frequency is determined by the

values of components connected to ROSC (pin

23) and COSC (pin 22) and calculated as follows:

f= 2

/ (R

* C

)

The frequency may varies from 225kHz to 275kHz

by adjusting the values of R

and C

. The

recommended values are C

= 220pF,

=120k

for a switching frequency of 250kHz.

The full H-bridge output stages use NMOS

transistors only. They therefore require bootstrap

capacitors for the high side of each output to turn

on correctly. A

220nF ceramic capacitor,

rated for at least 25V, must be connected from

each output to its corresponding bootstrap input.

Specifically, one 220nF capacitor must be

connected from xOUTP to xBSP, and another

220nF capacitor from xOUTN to xBSN. It is

To ensure that the maximum gate-to-source

voltage for the NMOS output transistors not

exceeded, two internal regulators are used to

clamp the gate voltage. Two 1μF capacitors must

be connected from VCLAMPL and VCLAMPR to

ground and must be rated for at least 25V. The

voltages at the VCLAMP terminals vary with V

and may not be used to power any other circuitry.

The AVDD terminal is the output of an internally-

generated 5V supply, used for the oscillator,

preamplifier, and volume control circuitry. It

requires a 0.1μF to 1μF capacitor, placed very

close to the pin to Ground to keep the regulator

stable. The regulator may not be used to power

any external circuitry.

Selection of C

and R

BSN and BSP Capacitors

VCLAMP Capacitors

Internal Regulated 5-V Supply (AVDD)

OSC

at least

ecommended to use 1 F BST capacitor to

replace 220nF (pin18, pin19, pin42 and pin43)

for lower than 100Hz applications.

The differential input stage of the amplifier

eliminates noises that appear on the two input

lines of the channel. To use the PAM8606 with a

differential source, connect the positive lead of

the audio source to the INP input and the negative

lead from the audio source to the INN input. To

use the PAM8606 with a single-ended source, ac-

ground the INP input through a capacitor equal in

value to the input capacitor on INN and apply the

audio source to the INN input. In a single-ended

input application, the INP input should be ac-

grounded at the audio source other than at the

device input for best noise performance.

Low-ESR

capacitors

a re

recommended

throughout this application section. A real (with

respect to ideal) capacitor can be modeled simply

as a resistor in series with an ideal capacitor. The

voltage drop across this resistor minimizes the

beneficial effects of the capacitor in the circuit.

The lower the equivalent value of this resistance

the more the real capacitor behaves as an ideal

capacitor.

The PAM8606 has short circuit protection circuitry

on the outputs to prevent damage to the device

when output-to-output shorts, output-to-GND

shorts, or output-to-VCC shorts occur. Once a

short-circuit is detected on the outputs, the output

drive is immediately disabled. This is a latched

fault and must be reset by cycling the voltage on

the

pin to a logic low and back to the logic high

state for normal operation. This will clear the

short-circuit flag and allow for normal operation if

the short was removed. If the short was not

removed, the protection circuitry will again

activate.

Thermal protection on the PAM8606 prevents

damage to the device when the internal die

temperature exceeds 150°C. There is a ±15

degree tolerance on this trip point from device to

device. Once the die temperature exceeds the set

thermal point, the device enters into the shutdown

state and the outputs are disabled. This is not a

latched fault. The thermal fault is cleared once the

temperature of the die is reduced by 40°C. The

device begins normal operation at this point

without external system intervention.

Differential Input

Using low-ESR Capacitors

Short-circuit Protection

Thermal Protection

Power Analog Microelectronics Inc

08/2008 Rev 1.1

PAM8606

6W Stereo Class-D Audio Power Amplifier with DC Volume Control

PAM8606 Datasheet(PDF) 14 Page - Power Analog Micoelectronics

PAM8606 Datasheet(HTML) 14 Page - Power Analog Micoelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Datasheet Download

Link URL