THAT1420 ETC [List of Unclassifed Manufacturers], THAT1420 Datasheet - Page 7

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

Rev. 4/24/01
Preliminary Information
tors whose purpose is to redirect this RF energy to
the chassis before it can circulate and effectively form
a single loop transformer that magnetically couples
RF into the remainder of the circuit. Ferrite beads
are also included to ensure that RFI current is di-
rected to the chassis and not through the relatively
low impedance (at RF frequencies) output of the
THAT 1420/1430. The devices will have no effect on
the gain error of these line drivers at audio frequen-
cies.
the rails, this protection might not be adequate for
some conditions seen in the field. The most obvious
problem that one might foresee would be having the
line driver’s output plugged directly into a micro-
phone preamplifier input that has +48V phantom
power applied.
currents of several amps, which can cause open cir-
cuits in the metal traces or failure of the protection
diodes on the IC.
While both of these chips have diode protection to
In
4
3
100n
100n
C4
C5
Figure 6. 1420 with output common mode offset protection, RFI protection, and surge protection
Gnd
In
This situation can result in surge
Vee
Vcc
THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA
5
VCC
6
VEE
Tel: [phone]; Fax: [phone]; Web: www.thatcorp.com
Sens+
Sens-
2
7
Out+
Out-
THAT1420
10u
10u
C1
C2
8
U1
1
SB160
SB160
D4
SB160
D6
SB160
D3
D5
posed of SB160’s to clamp potentially damaging
surges to the IC’s supply rails.
Closing thoughts
highly useful, cost-effective functional blocks that can
provide significant improvement over discrete de-
signs. The THAT 1420 and 1430 go a step or two
further by improving over existing components. Both
incorporate OutSmartsä technology to tame the ab-
errant single-ended clipping behavior of conventional
cross-coupled output stages. The THAT 1430's de-
sign gives reasonably low output offset voltage with
only a resistor and a single film or ceramic capacitor,
though it is not pin-compatible with existing IC out-
put stages.
Corporation integrated circuits, please contact us di-
rectly, or through one of our international distribu-
tors.
Ferrite Bead
This circuit uses a discrete diode bridge com-
The integrated balanced line driver is one of those
For more information on these or other THAT
Ferrite Bead
L2
L1
C3
100p
100p
C8
Out Hi
Out Lo
Page 7