DL200 Datasheet, PDF (411/670 Pages) Motorola, Inc – Sensor

Freescale Semiconductor, Inc.
Characteristics
Power Supply Voltage
Full Scale Pressure
– MPX2010
– MPX2050
– MPX2100
– MPX2200
Full Scale Output
Zero Pressure Offset
Sensitivity
Quiescent Current
Table 1. Specifications
Symbol
Min
Typ
B⁺
10
PFS
fFS
fOFF
SAOUT
ICC
10
1
9/PFS
55
AN1316
Max
Units
30
Volts
10
kPa
50
kPa
100
kPa
200
kPa
kHz
kHz
kHz/kPa
mA
EVALUATION BOARD
The following sections present an example of the signal
conditioning, including frequency conversion, that was
developed as an evaluation tool for the Motorola MPX2000
series pressure sensors. A summary of the information
required to use evaluation board number DEVB160 is
presented as follows.
Description
The evaluation board shown in Figure 1 is designed to
transduce pressure, vacuum or differential pressure into a
single–ended, ground referenced voltage that is then input to
a voltage–to–frequency converter. It nominally provides a 1
kHz output at zero pressure and 10 kHz at full scale pressure.
Zero pressure calibration is made with a trimpot that is located
on the lower half of the left side of the board, while the full scale
output can be calibrated via another trimpot just above the
offset adjust. The board comes with an MPX2100DP sensor
installed, but will accommodate any MPX2000 series sensor.
One additional modification that may be required is that the
gain of the circuit must be increased slightly when using an
MPX2010 sensor. Specifically, the resistor R5 must be
increased from 7.5 kΩ to 12 kΩ.
Circuit Description
The following pin description and circuit operation
corresponds to the schematic shown in Figure 2.
Pin–by–Pin Description
B⁺:
Input power is supplied at the B⁺ terminal of connector CN1.
Minimum input voltage is 10 V and maximum is 30 V.
Fout:
A logic–level (5 V) frequency output is supplied at the OUT
terminal (CN1). The nominal signal it provides is 1 kHz at zero
pressure and 10 kHz at full scale pressure. Zero pressure
frequency is adjustable and set with R12. Full–scale
frequency is calibrated via R13. This output is designed to be
directly connected to a microcontroller timer system
input–capture channel.
GND:
The ground terminal on connector CN1 is intended for use
as the power supply return and signal common. Test point
terminal TP3 is also connected to ground, for measurement
convenience.
TP1:
Test point 1 is connected to the final frequency output, F_out.
TP2:
Test point 2 is connected to the +5 V regulator output. It can
be used to verify that this supply voltage is within its tolerance.
TP3:
Test point 3 is the additional ground point mentioned above
in the GND description.
TP4:
Test point 4 is connected to the +8 V regulator output. It can
be used to verify that this supply voltage is within its tolerance.
P1, P2:
Pressure and Vacuum ports P1 and P2 protrude from the
sensor on the right side of the board. Pressure port P1 is on
the top (marked side of package) and vacuum port P2, if
present, is on the bottom. When the board is set up with a dual
ported sensor (DP suffix), pressure applied to P1, vacuum
applied to P2 or a differential pressure applied between the
two all produce the same output voltage per kPa of input.
Neither port is labeled. Absolute maximum differential
pressure is 700 kPa.
Motorola Sensor Device Data _{For Mor}w_eww_In.m_foot_ro_mro_ala_t.c_ioom_n/s_Oem_nic_To_hnd_isuc_Pto_rr_os _duct,
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