PM9106AP
The most important external components for the SA9106AP device are:
C
1
and C
2
are the outer loop capacitors for the two integrated oversampling A/D
converters. The value of these capacitors is 560pF.
The actual values determine signal to noise and stability performance. The optimum
tolerances should be within ± 10%.
C
3
and C
4
are the inner loop capacitors of the A/D converters. The optimum value
is 3.3nF. The actual values are uncritical. Values smaller than 0.5nF and larger than
5nF should be avoided.
R
2
, R
1
and R
SH
are the resistors defining the current level into the current sense input.
The values should be selected for an input current of 16µA
RMS
into the SA9106AP
at rated line current.
Values for RSH of less than 200µΩ should be avoided.
R
1
= R
2
= (I
L
/16µA
RMS
) * R
SH
/2
Where
I
L
=
R
SH
=
Line current
Shunt resistor/termination resistor
R
3
, R
5
and R
4
set the current for the voltage sense input. The values should be
selected so that the input current into the voltage sense input (virtual ground) is set
to 14µA.
R
7
defines all on-chip bias and reference currents. With R
7
= 24kΩ, optimum
conditions are set.
XTAL is a colour burst TV crystal (f = 3.5795MHz) for the oscillator. The oscillator
frequency is divided down to 1.7897MHz on-chip and supplies the A/D converters
and the digital circuitry.
sames
5/10
SAMES [ SAMES ]
