PICCOLO power amplifier module

APP SI – Abbate Pier Paolo Studio Ingegneria – Italy – email: [email protected]
PICCOLO
power amplifier module
description:
Piccolo is an high performances power amplifier module based on the world
famous LM3886 IC by National Semiconductor. Piccolo's design is centered on the
following points:
– high stability operation
on “real” loads without inductance on output to
stabilize the amp.
– reduction to all paths to increase sound performances and to reduce noise:
signal path, ground return paths and power supply paths has been reduced as
well as possible, so the power supply section has been inserted into the same
PCB of the amp section to reduce ground and power supply paths. Moreover
ground star topology is used. It result a very impressive “quite” sound
operation.
– optimal stages polarization. The offset voltage is reduced as well as possible to
achieve the best operation of LM3886's internal stages.
feautures:
–
Based on the world famous National LM3886 integrated circuit audio
amplifier, used in several “gainclone” projects.
–
Power supply inside the same amplifier section board, requires an
power transformer with two separate secondaries
–
68W cont. avg. output power into 4Ω at dual VAC = 20V supply
50W cont. avg. output power into 8Ω at dual VAC = 25V supply
30W cont. avg. output power into 8Ω at dual VAC = 18V supply
(preferred choise for high current operation)
–
Sophisticated thermal and output protections inside the LM3886
internal circuitry. Automute function to avoid “on/off” transients.
–
Very low distortion and noise.
–
High quality “professional grade” vetronite PCB.
–
Fits the Design Build Listen ezChassis.
–
Ready to be used in integrated or final amplifier configuration without
using an active preamp section, requires a 10Kohm stereo log.
potentiometer for the passive preamp (see the application note 1).
–
ideal for Self-powered speakers.
specifications (typical values):
-
suggested power supply voltages
18 + 18 VAC
-
max power supply voltages
25 + 25 VAC
-
suggested trasformer powers
80 – 120 VA
-
output power
cont. avg. output power into 8Ω at
cont. avg. output power into 4Ω at
cont. avg. output power into 4Ω at
cont. avg. output power into 8Ω at
cont. avg. output power into 8Ω at
Instantaneous Peak Output Power
dual
dual
dual
dual
dual
VAC
VAC
VAC
VAC
VAC
=
=
=
=
=
18V
18V
20V
20V
25V
30W
56W
68W
38W
50W
135W
-
total Harmonic distortion Plus Noise THD + N
30W, RL = 8Ω, 20 Hz ≤ f ≤ 20 kHz
0,03 %
-
intermodulation distortion Test IMD (8Ω load)
60 Hz, 7 kHz, 4:1 (SMPTE)
60 Hz, 7 kHz, 1:1 (SMPTE)
0.004 %
0.009 %
signal-to-noise ratio SNR
(A-Weighted , measured at 1 kHz)
Po = 1W,
Po = 60W,
90 dB
106 dB
-
-
bandwith
Po=1W, RL = 8Ω, +/- 3dB
-
output current
-
quiescent currents
mesured with +/- 25V supply, no LED,
no load , no input signal, Tc=75°C:
18 Hz – 110 KHz
internally limited
at 11.5 A
-
input impedance
around 40 mA
per each rail
30KΩ
-
gain
30 dB
THIS IS THE PICCOLO'S TOP VIEW
THIS IS THE INTERNAL SCHEMATIC OF THE APP SI PICCOLO BOARD
DISCLAIMER:
COPYRIGHT 2009 - Abbate Pier Paolo Studio Ingegneria , ALL RIGHTS RESERVED. THIS PRODUCT IS
NOT FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT. Abbate Pier Paolo Studio Ingegneria
RESERVES THE RIGHT TO MAKE CHANGES TO THIS PRODUCT AND THIS DOCUMENT WITHOUT FURTHER
NOTICE. THIS DOCUMENTS IS NOT INTENDED LIKE LICENCE OR SALE OR GIFT OF INTELLECTUAL
PROPERTIES REGARDING THE PRODUCTS HEREIN DESCRIBED.Abbate Pier Paolo Studio Ingegneria
AND PIER PAOLO ABBATE DECLINE ANY RESPONSABILITY, ANY LIABILITY, ANY WARRANTY REGARDING
THE PRODUCTS AND THE INFORMATIONS HEREIN DESCRIBED. The only reference to any court
litigation is the Palermo court in Italy.