Information

ManualsBrandsNXP Semiconductors ManualsActive ComponentsPressure sensor 1 pc(s) MPX5100DP 0 kPa up to 100 kPa Print

1Motorola Sensor Device Data

Prepared by: Warren Schultz

Discrete Applications Engineering

INTRODUCTION

Integrated semiconductor pressure sensors such as the

MPX5100 greatly simplify electronic measurement of

pressure. These devices translate pressure into a 0.5 to 4.5

volt output range that is designed to be directly compatible

with microcomputer A/D inputs. The 0.5 to 4.5 volt range also

facilitates interface with ICs such as the LM3914, making Bar

Graph Pressure Gauges relatively simple. A description of a

Bar Graph Pressure Sensor Evaluation Board and its design

considerations are presented here.

Figure 1. DEVB129 MPX5100 Bar Graph Pressure Gauge

Order this document

by AN1304/D

SEMICONDUCTOR APPLICATION NOTE

 Motorola, Inc. 1997

REV 1

Summary of content (6 pages)

PAGE 1
Order this document by AN1304/D SEMICONDUCTOR APPLICATION NOTE ! ! Prepared by: Warren Schultz Discrete Applications Engineering INTRODUCTION Integrated semiconductor pressure sensors such as the MPX5100 greatly simplify electronic measurement of pressure. These devices translate pressure into a 0.5 to 4.5 volt output range that is designed to be directly compatible with microcomputer A/D inputs. The 0.5 to 4.
PAGE 2
AN1304 EVALUATION BOARD DESCRIPTION A summary of the information required to use evaluation board number DEVB129 is presented as follows. A discussion of the design appears under the heading Design Considerations. FUNCTION The evaluation board shown in Figure 1 is designed to provide a 100 kPa full scale pressure measurement. It has two input ports. P1, the pressure port is on the top side of the MPX5100 sensor, and P2, a vacuum port, is on the bottom side.
PAGE 3
AN1304 DESIGN CONSIDERATIONS In this type of an application the design challenge is how to interface a sensor with the bar graph output. MPX5100 Sensors and LM3914 Bar Graph Display drivers fit together so cleanly that having selected these two devices the rest of the design is quite straight forward. A block diagram that appears in Figure 4 shows the LM3914’s internal architecture.
PAGE 4
AN1304 MPX5100 PRESSURE GAUGE MOTOROLA DISCRETE APPLICATIONS PRESSURE kPa 100 90 70 60 LM3914 MV57164 80 50 MPX5100 40 30 20 C2 10 C1 B+ TP2 R3 U3 OUT TP1 R2 GND ON DEVB129 R6 GND R5 OFF ZERO FULL SCALE Figure 3. Silk Screen 2X Table 1. Parts List Designators Quant. Description Rating Manufacturer Part Number 0.
PAGE 5
AN1304 LED V+ LM3914 RHI REF OUT 6 7 + THIS LOAD DETERMINES LED BRIGHTNESS REF ADJ V+ – + REFERENCE VOLTAGE SOURCE 1.25 V – 8 3 1k – + 11 1k – + 12 1k – + 13 1k – + 14 – + 15 – + 16 1k – + 17 1k – + 18 1k – + 1 1k 1k 1k RLO COMPARATOR 1 of 10 10 V+ FROM PIN 11 4 MODE SELECT AMPLIFIER 9 – BUFFER SIG IN 5 CONTROLS TYPE OF DISPLAY, BAR OR SINGLE LED 2 V– 20 k + Figure 4.
PAGE 6
AN1304 Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages.