GP34119 GTM, GP34119 Datasheet - Page 4

• Manufacturer Part Number: GP34119
• Description: LOW POWER AUDIO AMPLIFIER
• Manufacturer: GTM

Chip Disable
the GP34119 is enabled for normal operation. When Pin 1 is at a Logic "1" (2.0 V to V
equivalent to a Logic "0", although good design practice dictates that an input should never be left open. Input impedance at Pin 1 is a
nominal 90 k . The power supply current (when disabled) is shown in Figure 19.
the audio output, from the application of the CD signal, is <2.0 us, and turn on-time is 12 ms-15 ms. Both times are independent of C1,C2,
and V
V
outputs (while disabled), they must be within the range of V
Power Dissipation
which can safely be dissipated within the GP34119 is found from the following equation: P
temperature; and
the load resistance.
Figures 8 to 10, along with Figures 11 to 13 (distortion curves), and a peak working load current of D 200 mA, define the operating range
for the GP34119. The operating range is further defined in terms of allowable load power in Figure 14 for loads of 8.0 , 16
left (ascending) portion of each of the three curves is defined by the power level at which 10% distortion occurs. The center flat portion of
each curve is defined by the maximum output current capability of the GP34119. The right (descending) portion of each curve is defined
by the maximum internal power dissipation of the IC at 25 : . At higher ambient temperatures, the maximum load power must be reduced
according to the above equations. Operating the device beyond the current and junction temperature limits will degrade long term
reliability.
Layout Considerations
stray capacitances, and the manner in which the speaker wires are configured, may dictate otherwise. Generally, the speaker wires should
be twisted tightly, and not more than a few inches in length.
Characteristics Curve
O2
The Chip Disable (Pin 1) can be used to power down the IC to conserve power, or for muting, or both. When at a Logic "0" (0 V to 0.8 V),
Muting, defined as the change in differential gain from normal operation to muted operation, is in excess of 70 dB. The turn-off time of
Figures 8 to 10 indicate the device dissipation (within the IC) for various combinations of V
The power dissipated within the GP34119, in a given application, is found from the following equation:
P
Normally a snubber is not needed at the output of the GP34119, unlike many other audio amplifiers. However, the PC board layout,
, change to a high impedance condition, removing the signal from the speaker. If signals from other sources are to be applied to the
D
When the GP34119 is disabled, the voltages at FC1 and FC2 do not change as they are powered from V
= (V
CC
Fig 1. Turn-On Time versus C1, C2 at Power-On
.
CC
x I
CC
) + (I
JA
is the package thermal resistance (100 : /W for the standard DIP package.)
RMS
x V
CC
) – (R
L
x I
RMS
2
) where I
CC
CC
is obtained from Figure 19; and I
and Ground.
Fig 2. Amplifier #1 Open Loop Gain and Phase
CC
V), the IC is disabled. If Pin 1 is open, that is
CC
RMS
D
, R
= (140 : -T
is the RMS current at the load; and R
L
, and load power. The maximum power
A
)/
ISSUED DATE :2005/02/18
REVISED DATE :
JA
CC
where T
. The outputs, V
A
is the ambient
and 32 . The
4/8
O1
and
L
is