TH7301 Datasheet, PDF (8/14 Pages) List of Unclassifed Manufacturers – Dual-Channel Programmable Low-Pass Filter

TH7301 Dual-Channel Programmable Low-Pass Filter
Application
Diagram
The application diagram below is an example
diagram and provided to assist the customer in
using the IC. The configuration can be changed
for other applications.
I channel
Input
C2
C1
-5 Vdc
C4
C5
Q channel
Input
C3
1 VCCI
IOUT 16
2 IIN
VEEI 15
3 IREF
SDATA 14
4 VDD
SCLK 13
TH7301
5 VSS
SDEN 12
6 QREF
RDAC 11
7 QIN
VEEQ 10
8 VCCQ
QOUT 9
I channel
Output
C6
R_DAC
3-wire
Serial
Interface
-5 Vdc
C7
Q channel
Output
Figure 4: Application Diagram
Component List
for Application
Diagram
The AC coupling capacitors (C1-C4) will produce
a high pass pole with the 3kΩ input resistance.
Their value should be chosen such that this pole
is below any frequencies of interest in the system.
Component
C1, C2, C3, C4
C5, C6, C7
R_DAC
Function
AC coupling capacitors
AC coupling capacitors
DAC current setting resistor
The Rdac resistor is the current setting resistor for
the DAC. The recommended values are listed
below.
Value
100
22
4.5
Unit
nF
nF
kΩ
Important notice
It is recommended to operate the device from a
single power supply for both analog and digital
sections of the device. Operation from separate
power supplies on VEE and VSS and absence of
the digital voltage may cause destruction of the
device.
The serial interface does not contain a power on
reset, thus all three registers must be programmed
after power on to prevent undefined logical states and
to achieve reliable filter operation. I. e. a first reset
word may reset all registers to 0.
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