TEA7063DP datasheet(5/15 Pages) STMICROELECTRONICS

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CIRCUIT DESCRIPTION

1. DC CHARACTERISTICS

1.1 VC (pin 17)

The stabilized voltage VC is connected to Vline

(pin 16) through an internal shunt regulator T1,

T2, which presents to the line a high AC imped-

ance at frequecncies higher than 200Hz. At this

purpose the value of C1 (at pin 17) must be not

lower than 47

µF (suggested value is 100µF).

The shunt regulator, T1 and T2, also controls the

extra current source, or power management, at

pin 12 (see also paragraph 6).

1.2 VLINE (pin 16)

The line voltage (pin 16) is determined by the

value of the external resistor R6 and by the inter-

nal current, Iint, flowing between VC (pin 17) and

Ground (see also paragr.: 1.1):

VLINE =VC +R 6 x Iint

VC is fixed by design at about 2.5V.

Iint is reversely related to R9:

Iint = 8 Volt/R9 + 60

µAat IL > 25mA

Iint = 4 Volt/R9 + 60

µAat IL = 6mA

where IL depends on ILB (see supply manage-

ment)

VLINE must be externally adjusted (with R6) to

guarantee both DC and AC characteristic in ac-

cordance to the specific standard of the different

adminastrations.

Another adjustment of the DC characteristic is

possible with R9. Increasing the value of R9

causes a decrease of Iint and consequently a re-

duction of the product Iint x R9. (see also Para-

graph 7)

Figure 2

Figure 1

TEA7063

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TEA7063DP Datasheet(PDF) 5 Page - STMicroelectronics