SPWLM386D Datasheet, PDF (2/6 Pages) SeCoS Halbleitertechnologie GmbH – Low Voltage Audio Power Amplifier

Elektronische Bauelemente
SPWLM386D
Low Voltage Audio Power
Amplifier
Abs olute Max imum R atings (Note 2)
P arameter
S ymbol
Value
Unit
Supply Voltage
VCC
15
V
Power Dissipation
Pd
1.25
W
Input Voltage
Vi
-0.4 ~ +0.4
V
Operating Temperature
Topr
0 ~ 70
к
Storage Temperature
Tstg
-65 ~ 150
к
Junction Temperature
Tj
150
к
Electrical Characteristics (TA=25к Note1, 2)
Parameter
Symbol
Test Conditions
Operating Supply Voltage
VS
Quiescent Current
IQ VS=6V, VIN=0
Output Power
PO
VS=6V, RL=8 , THD=10%
VS=9V, RL=8 , THD=10%
Voltage Gain
GV
VS=6V, f=1kHz
10 F form Pin1 to Pin8
Bandwidth
BW VS=6V, Pin1 to Pin8 open
Total Harmonic Distortion
THD
PO=125mW, VS=6V, f=1kHz
RL=8 , Pin1 to Pin8 open
Power Supply Rejection
Ration
PSRR
VS=6V, f=1kHz, CBYPASS=10 F Pin1
and Pin8 open, Referred to output
Input Resistance
RIN
Input Bias Current
IBIAS VS=6V, Pin2 to Pin3 open
Min Typ. Max. Unit
4
-
12
V
-
4
8 mA
230 -
480 -
-
-
mW
-
26
46
-
dB
- 300 - kHz
-
0.2
-
%
-
50
-
dB
-
50
-
k
- 250 -
nA
Note1: All voltages are measured with respect to the ground pin, unless otherwise specified.
Note2: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions
for which the device is functional, but do not guarantee specific performance limits. Electrical Characteristics state DC and AC
electrical specifications under particular test conditions which guarantee specific performance limits. This assumes that the device
is within the Operating Ratings.
Specifications are not guaranteed for parameters where no limit is given, however, the typical value is a good indication of device
performance.
this pin (with a 5.0uF capacitor at Pin 2)
Note3: For operation in ambient temperatures above 25к, the device must be derated based on_oa_n 1_t5_im0к_{e o}m_f a_thxi_em_cu_im_rcuju_itnc_istio_an_fft_ee_cm_tep_der_ba_ytur_the_e
and 1) a thermal resistance of 107к/W, junction to ambient for the dual-in-line package and 2)a thermal resistance of 170 к/W for
the small outline package.
nd resistor set low frequency rolloff and input impedance. The
Application Hints
Gina Control
To make the SPWLM386D a more versatile amplifier, two pins (1 and 8) are provided for gain control. With pins 1 and 8 open the 1.35K
resistor sets the gain at 20 (26dB),If a capacitor is put from pin 1 to 8,bypassing the 1.35k resistor, the gain will go up to 200 (46dB). If a
resistor is placed in series with the capacitor the gain can be set to any value from 20 to 200.Gain control can also be done by capacitively
coupling a resistor (or FET) prom pin 1 to ground.
Additional external components can be placed in parallel with the internal feedback resistors to tailor the gain and frequency response for
individual applications. For example we can compensate poor speaker bass response by frequency shaping the feedback path. This is
done with a series RC from pin 1 to 5 (paralleling the internal 15k resistor). For 6 dB effective bass boost: R=15k , the lowest value for
good stable operation in R=10k , if pin 8 is open, If pins 1 and 8 are bypassed then R as low as 2k can be used. This restriction is
because the amplifier is only compensated for closed-loop gains greater than 9.
Input Biasing
The schematic show that both input are biased to ground with a 50k resistor. The base current of the input transistors is about 250nA, so
the inputs are at about 12.5mW when left open. If the dc source resistance driving the SPWLM386D is higher than 250k it will contribute
very little additional offset (about 2.5mW at the input, 50mW at the output). If the dc source resistance is less than 10k, then shorting the
unused input to ground will keep the offset low (about 2.5mW at the input, 50mW at the output). For dc source resistance between these
values we can eliminate excess offset by putting a resistor from the unused input to ground, equal in value to the dc source resistance. Of
course all offset problems are eliminated if the input is capacitively coupled.
When using the SPWLM386D with higher gains (bypassing the 1.35k resistor between pin1 and 8) it is necessary to bypass the unused
input, preventing degradation of gain and possible instabilities. This is done with a 0.1 F capacitor or a short to ground depending on the
dc source resistance on the driven input.
http://www.SeCoSGmbH.com/
01-Jun-2002 Rev. A
Any changing of specification will not be informed individual
Page 2 of 6