ZXCT1050 Precision wide input range current monitor Description The ZXCT1050 is a wide input range current The very low offset voltage enables a typical monitor, which operates over a range of input accuracy of 1% for sense voltages of only 30mV, voltages from ground up to V -2V. As a giving better tolerances for small sense CC result the ZXCT1050 can be used on the high resistors necessary at higher currents. or low side of the load. The ZXCT1050 provides variable gain by using two external resistors. The first of which sets the transconductance and the second setting the overall gain. Features Applications Accurate down to end current sensing Power supply Output voltage scaling x10 DC motor and solenoid control 0 to V -2V sense input range Battery management CC 2.7 to 20V supply range Over current monitor 50A quiescent current Power management SOT23-5 package Short circuit detection Pin connections Typical application circuit R SENSE IN V 1 5 SENSE- CC R SHUNT 2 GND SENSE+ SENSE- OUT 3 4 SENSE+ ZXCT1050 V CC Load OUT OUT R GAIN Ordering information Order code Pack Part mark Reel size Tape width Quantity (inches) (mm) per reel ZXCT1050E5TA SOT23-5 1050 7 8 3000 Issue 1 - June 2007 1 www.zetex.com Zetex Semiconductors plc 2007ZXCT1050 Absolute maximum ratings V max. 20V CC Voltage on SENSE- and SENSE+ -0.6 to V CC Voltage on all other pins -0.6V and V +0.6V CC V = (V +) - (V -) 500mV SENSE SENSE SENSE Operating temperature -40 to 125C Storage temperature -55 to 150C Maximum junction temperature 150C * Package power dissipation 300mW at T = 25C (De-rate to zero for T = 150C) A J Operation above the absolute maximum rating may cause device failure. Operation at the absolute maximum ratings, for extended periods, may reduce device reliability. Recommended operating conditions Parameter Min. Max. Units V Common-mode sense input range 0 V -2 V SENSE+ CC V Supply voltage range 2.7 20 V CC V Differential sense input voltage range 10 300 mV SENSE V Output voltage range 0 V -2 V OUT CC T Ambient temperature range -40 125 C A Recommended resistor gain setting combinations Gain R R SH G 10 7.5k 3.75k 20 7.5k 7.5k 50 7.5k 18.7k 100 7.5k 37.5k 20 3.75k 3.75k 50 1.5k 3.75k 100 750 3.75k Pin function table PIN Name Description 1V This is the analog supply and provides power to internal circuitry. CC 2 GND Ground pin. 3 OUT Output pin. A resistor, R , connected from this pin pin down to ground GAIN develops an output voltage. 4 SENSE+ This is the positive input of the current monitor and has an input range from 0V up to V 2V. CC 5 SENSE- This is the negative input of the current monitor and has an input range from 0V up to V 2V. The current through this pin varies with differential sense CC voltage. A resistor, R , from this pin to the rail being sensed set the SHUNT transconductance of the current monitor. Issue 1 - June 2007 2 www.zetex.com Zetex Semiconductors plc 2007