THAT4311 Datasheet, PDF (1/12 Pages) List of Unclassifed Manufacturers – Low-voltage, Low-power Analog Engine Dynamics Processor

T H AT Corporation
FEATURES
· High Performance VCA, RMS-Level
Detector, and three 0pamps in one
package
· Wide Dynamic Range: >105 dB
· Low THD: <0.09%
· Low Power: 7 mA typ.
· Surface-Mount Package
· 5 VDC Operation
Low-voltage, Low-power
Analog Engine^® Dynamics Processor
THAT 4311
APPLICATIONS
· Wireless microphone systems
· Wireless in-ear monitors
· Compressors and Limiters
· Gates
· De-Essers
· Duckers
Description
The THAT 4311 Low Power Dynamics Proces-
sor combines in a single IC all the active circuitry
needed to construct a wide range of dynamics
processors. The 4311 includes a high perfor-
mance, voltage controlled amplifier, a log re-
sponding RMS-level sensor and three opamps,
one of which is dedicated to the VCA, while the
other two may be used for the signal path or con-
trol voltage processing.
The exponentially-controlled VCA provides
two opposing-polarity, voltage sensitive control
ports. Dynamic range exceeds 105 dB, and THD
is typically 0.09% at 0dB gain. The RMS detector
provides accurate RMS to DC conversion over an
80 dB dynamic range.
Though originally designed for use in micro-
phone noise reduction systems, the 4311 is a use-
ful building block in a number of analog signal
processing applications. The combination of ex-
ponential VCA gain control and logarithmic detec-
tor response - “decibel-linear” response -
simplifies the mathematics of designing the con-
trol paths of dynamics processors, making it easy
to develop audio compressors, limiters, gates, ex-
panders, de-essers, duckers, and the like. The
high level of integration ensures excellent temper-
ature tracking between the VCA and the detector,
while minimizing the external parts count.
18
17 16 15 14
13
12 11
19
EC- EC+ SYM
OA1
20
IN _VCA OUT
THAT4311
CT
1
IN _RMS
IT
OUT
OA2
VCC
OA3
VREF
VREF
2
3
45
67 8 9
VEE
10
Figure 1. THAT 4311 equivalent block diagram
Pin Name
RMS IN
IT (ITIME)
OA2 -IN
RMS OUT
CT (CTIME)
CLIP
OA2 OUT
CAP
VREF
VEE
VCC
OA3 OUT
VCA OUT
SYM
EC+
EC-
VCA IN
OA1 OUT
OA1 -IN
OA1 +IN
DMP20
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Table 1. THAT 4311 pin assignments
THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA
Tel: [phone]; Fax: [phone]; Web: www.thatcorp.com