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The output signal is adjustable between 0.5V and 4.5V (when operating with 5V supplies), and

it accommodates sensor sensitivities of 10mV/V and higher. All coefficients required for

compensation are held in an EEPROM internal to the MAX1458. Thus, the setup is easily and

automatically calibrated via a simple 4-wire serial interface.

Because the relationship between measured differential pressure and liquid flow rate depends

on the liquid's viscosity, which in turn changes with temperature, the MAX1458 provides a

temperature output signal for use in external signal processing. This setup (Figure 4) allows the

measurement of flow rates no higher than 5.5µl/sec. The analog pressure signals, the

temperature sensor terminals, and all other connections are made accessible at a connector for

external post?processing.