8.5.1. MP3V5050GP (Freescale)

8.5.1.1. Introduction

The MP3V5050 series piezoresistive transducer is a state-of-the-art monolithic silicon pressure sensor designed for a wide range of applications, but particularly those employing a microcontroller or microprocessor with A/D inputs. Patented silicon shear stress strain gauge. Barbed side ports for robust tube connection.

Range is 0-50 kPa with a sensitivity of 54 mV/kPa. It has 2.5% maximum error over 0° to 85°C.

8.5.1.2. Applications

Can be used to sense liquid level in containers or overhead storage tanks.

8.5.1.3. Resources

8.5.1.4. Platform Integration

The sensor can be enabled by defining compile-time flag PLTFRM_MP3V5050GP_ENA.

8.5.1.4.1. Functions

PLTFRM_sts_t MP3V5050GP_init(UINT8_t devId)

Initializes the sensor interface by configuring GPIO. Currently, the device is configured for P2.0. There is no callback function associated with the device since the sensor is typically read when required. This function is typically called during platform initialization.

Parameters:
  • devId – Identity of the device.
Returns:

PLTFRM_STS_SUCCESS is returned on success. A non-zero value indicates a failure. One possible error is PLTFRM_STS_INV_DEV_ID.

PLTFRM_sts_t MP3V5050GP_getSensorOutput(UINT8_t devId, UINT32_t *snsrOp_p, UINT32_t *snsrVcc_p)

Obtain the sensed value. Instead of pressure, voltage is returned. Application has to calibrate and translate this to pressure. Because the sensor output depends on the Vcc power supply, this is also sensed and returned.

Parameters:
  • devId – Identity of the device.
  • snsrOp_p – Points to location where output from the sensor is returned in millivolts.
  • snsrVcc_p – Points to location where power supply value is returned in millivolts.
Returns:

PLTFRM_STS_SUCCESS is returned on success. A non-zero value indicates a failure. One possible error is PLTFRM_STS_INV_DEV_ID.

8.5.1.4.2. Macros

#define MP4V5050GP_SENSOR_OUTPUT_VALUE_SZ  4
#define MP4V5050GP_SENSOR_VCC_VALUE_SZ  4

8.5.1.4.3. Type Definitions

typedef struct
{
   UINT8_t devId;
   PLTFRM_gpioPortId_t portId;
   PLTFRM_gpioPortPin_t portPinNr;
} MP3V5050GP_cntxt_s;