a2tpmi PerkinElmer, a2tpmi Datasheet - Page 12

• Manufacturer Part Number: a2tpmi
• Description: Thermopile With Integrated Signal Processing Circuit
• Manufacturer: PerkinElmer

A2TPMI Datasheet Rev4
OUTPUT SIGNAL
The A2TPMI amplifiers are realized in chopper amplifier technology. Due to the nature of this technol-
ogy the output signals V
the range of 250 kHz. This AC voltage can be suppressed either by an electrical low pass filter or via an
additional software filtering.
In applications with low resistive load ( > 1Mohm) a simple RC low pass filter as follows can be used to
smooth the signal:
In applications with high resistive load (50kOhm … 1MOhm) filtering can be achieved with the following
circuit. A rail to rail OPAmp like the LMV358 should be used so that the full sensing range will be avail-
able on the output of the filter circuit.
PRINTED CIRCUIT BOARD (PCB) VERSION
Two different sizes of standard PCB versions are available. P1 version is a 17 x 34 mm
allows assembly of additional external mirror optics (M options). P3 version is 17 x 20 mm
able for applications with restricted space. P3 version is not available with mirror (M option).
Each PCB version is available either as plain version (sensor directly wired to connector), or with 1
order (RC-circuit, L1 option) or 2
provide attenuation of the AC portion on the output signal as described in chapter Output Signal.
A2TPMI
V
Tobj
A2TPMI
V
Tobj
or V
or V
Tamb
Tamb
R = 10kOhms
C = 100nF
500 Ohms
Tobj
R
and V
Tamb
nd
R
³470 nF
C
order (active OpAmp circuit, L2 option) low pass filter, in order to
incorporate an AC signal of approximately 10 mV peak to peak in
V
Tobj
or V
Tamb filtered
Page 12 of 21
C
LMV358
+
-
Datasheet
V
Tobj
or V
L1 Option
L2 Option
Tamb filtered
A2TPMI
Rev. Oct 2003
2
2
PCB which
PCB suit-
Ô
st