THAT1420 ETC [List of Unclassifed Manufacturers], THAT1420 Datasheet - Page 3

• Manufacturer Part Number: THAT1420
• Description: Balanced Line Drivers
• Manufacturer: ETC [List of Unclassifed Manufacturers]

Rev. 4/24/01
Preliminary Information
OutSmartsÔ technology
both employing the OutSmarts topology, a variation
of circuitry originally developed at Audio Toys, Inc.
OutSmarts topology employs two negative-feedback
loops -- one to control the differential signal, and a
separate loop to control the common mode output
levels.
both the THAT 1420 and 1430. The gain core is a
single amplifier that includes two differential input
pairs, C
V
out+
Parameter
Differential Output Offset
Differential Output
Voltage Swing,Pos
Differential Output
Voltage Swing,Neg
Output Impedance
Quiescent Supply Current
Short Circuit Output Current
Voltage Supply Range
The THAT 1420 and 1430 are similar devices,
Figures 2 and 3 show the gain core common to
and V
in+/-
out-,
and D
Vcc
Gnd
In+
Vee
related to each other by two gain ex-
in+/-
THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA
Tel: [phone]; Fax: [phone]; Web: www.thatcorp.com
, and complementary outputs,
5k
5k
Electrical Characteristics (cont’d.)
Symbol
V
I
Z
OOD
I
SC
S
Cin+
Cin-
O
Din+
Din-
Figure 2. THAT 1420 Equivalent Circuit Diagram
Theory of Operation
A
D
10k
10k
&
A
C
Dout-
Dout+
Unloaded, V
V
V
Conditions
R
10k
10k
IN
IN
L
=600W
= ±18V
= ±18V
pressions, A
tial inputs, D
feedback network between the outputs and the input
signal. The second differential input pair, C
connected to a bridge circuit which generates an er-
ror signal that is used to servo the common-mode be-
havior of the outputs. The loop equations are then,
where A
where A
IN
= 0
D
D
OUT
OUT
10k
10k
50
50
D
C
+
+
is the common-mode open-loop gain.
is the differential open-loop gain, and
THAT 1420
-
+
D
D
D
10p
(s) and A
in+/-
OUT
OUT
Min.
-10
40
60
±4
-
, are connected to the differential
-
20k
20k
=
=
D
å
C
D
(s). The first pair of differen-
V
D
V
Typ.
OUT
Out-
Sens+
Sens-
Out+
EE
±4
CC
50
70
OUT
4
+2
-2
=
=
A
A
D
Max.
C
±18
5.2
(
10
60
(
C
C
D
C
EXT
EXT
IN
IN
+
+
-
-
D
C
IN
IN
Units
mV
mA
mA
in+/-
V
V
W
V
-
-
Page 3
)
)
, is