Class-D Audio Power Amplifier
Preliminary Technical Data
AD1990/AD1992/AD1994/AD1996
GENERAL DESCRIPTION
FEATURES
The AD199x is a two channel Bridge Tied Load (BTL)
Integrated Stereo Modulator & Power Stage
0.005% THD+N
101.5dB Dynamic Range
PSRR > 65 dB
switching audio power amplifier with integrated ∑∆ modulator.
The modulator accepts a 1Vrms input signal (maximum power)
and generates a switching waveform to drive speakers directly.
One of the two modulators can control both output stages
providing twice the current for single-channel applications. A
digital, microcontroller-compatible interface provides control of
reset, mute and PGA gain as well as output signals for thermal
and over-current error conditions. The output stage can operate
from supply voltages ranging from 8V to 20V. The analog
modulator and digital logic operate from a 5V supply.
RDS-ON < 0.3 Ω (per transistor)
Efficiency > 80% @ 5W/6 Ω
EMI Optimized Modulator
On-Off-Mute Pop Noise Suppression
Short Circuit Protection
Over-Temperature Protection
Low Cost DMOS Process
APPLICATIONS
AD1990: 5Wx2 (10Wx1)
AD1992: 10Wx2 (20Wx1)
AD1994: 25Wx2 (50Wx1)
AD1996: 40Wx2 (80Wx1)
Flat Panel Televisions
Automotive Amplifiers
PC Audio Systems
Mini Components
62
63
60
53
50
51
32
31
LEFT CHANNEL
RIGHT CHANNEL
41,42
PVDD2
7,8
PVDD
PVDD2
DRIVER
HIGH SIDE
43,44,45
OUTR+
4,5,6
OUTL+
DRIVER
LOW SIDE
LEVEL
SHIFT
+
DEAD
TIME
LEVEL
SHIFT
+
DEAD
TIME
1,2,3
PGND1
9,10
PVDD1
46,47,48
PGND2
39,40
PGND2
PVDD2
Σ∆
MODULATOR
Σ∆
MODULATOR
PGA
PGA
PVDD2
CONTROL
CONTROL
DRIVER
DRIVER
HIGH SIDE
HIGH SIDE
11,12,13
OUTL-
36,37,38
OUTR-
DRIVER
DRIVER
LOW SIDE
LOW SIDE
14,15,16
PGND1
33,34,35
PGND2
PGND1
PGND2
Ø1
Ø2
Ø1
Ø2
55
REF_FILT
VOLTAGE
REFERENCE
57
AVDD
MUTE/
POP
CONTROL
56
AGND
OSCILLATOR
MODE CONTROL LOGIC
TEMPERATURE
SENSE &
OVER-CURRENT
PROTECTION
24,25
DVDD
23,26
DGND
27
CLKI
28
CLKO
30
29
19
18
17
49
22 21 20
Figure 1. Block Diagram
Rev. PrA – 1/20/05
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