ZXCT1051E5TA

ZXCT1051 Precision wide input range current monitor Description The ZXCT1051 is a wide input range current monitor, which operates over a range of input voltages from ground up to VCC-2V. As a result the ZXCT1051 can be used on the high or low side of the load. The ZXCT1051 provides a fixed gain of 10 thereby removing the need for an additional resistor. The very low offset voltage enables a typical accuracy of 1% for sense voltages of only 30mV, giving better tolerances for small sense resistors necessary at higher currents. Features Applications • Accurate down to end current sensing • Power supply • Output voltage scaling x10 • DC motor and solenoid control • 0 to VCC-2V sense input range • Battery management • 2.7 to 20V supply range • Over current monitor • 50 µA quiescent current • Power management • 1% typical accuracy • Short circuit detection • SOT23-5 package Pin connections Typical application circuit VCC VSENSEVSENSE+ VSENSE- GND VOUT VSENSE- RSENSE VSENSE+ VCC VSENSE+ ZXCT1051 GND VOUT VOUT Ordering information Order code Package Partmark Reel size (inches) Tape width (mm) Quantity per reel ZXCT1051E5TA SOT23-5 1051 7 8 3,000 Issue 2 - November 2006 © Zetex Semiconductors plc 2006 1 www.zetex.com ZXCT1051 Absolute maximum ratings VCC max. 20V Voltage on VSENSE- and VSENSE+ -0.6 to VCC Voltage on all other pins -0.6V and VCC +0.6V VSENSE "(VSENSE+) - (VSENSE-) 500mV Operating temperature, Tamb -40 to 125°C Storage temperature -55 to 150°C Maximum junction temperature 150°C Package power dissipation 300mW at Tamb = 25°C (de-rate to zero at 150°C) 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 0 VCC-2 V 2.7 20 V VSENSE+ Common-mode sense input range VCC Supply voltage range VSENSE Differential sense input voltage range 0 0.3 V VOUT Output voltage range 0 VCC - 2 V Tamb Ambient temperature range -40 125 °C Pin function table Pin Name Description 1 VCC This is the analog supply and provides power to internal circuitry 2 GND Ground pin 3 OUT Output voltage pin. 4 VSENSE+ This is the positive input of the current monitor and has an input range from 0V up to VCC – 2V. 5 VSENSE- This is the negative input of the current monitor and has an input range from 0V up to VCC – 2V. The current through this pin varies with differential sense voltage. Issue 2 - November 2006 © Zetex Semiconductors plc 2006 2 www.zetex.com ZXCT1051 Electrical characteristics Test conditions Tamb = 25°C, VSENSE+ = 10V, VCC = 12V, VSENSE = 100mV Symbol Parameter Conditions Min. Typ. Max. IQ VCC pin current VSENSE = 0V VOUT Output voltage VSENSE = 0V =30mV =100mV =150mV 45 70 µA 6 300 1.00 1.50 15 309 1.02 1.55 mV mV V V ISENSE+ VSENSE+ input current VSENSE = 0V 10 150 nA ISENSE- VSENSE- input current VSENSE = 0V 60 150 nA VOUT TC VOUT variation with temperature 300 ppm/°C ROUT Output resistance Gain VOUT/VSENSE Accuracy Total output error BW Bandwidth 0 291 0.98 1.45 See note (b) 2.5 3.75 Units 5 k⍀ 2 % 10 -2 VSENSE(DC) VSENSE(AC) = 10mV = 10mVPP CL = 5pF, VSENSE(DC) = 100mV 300 kHz 1 MHz PSRR Power supply VCC = 2.7V to 20V rejection ratio refered VSENSE- = 0V to output 58 dB CMRR Common mode VCC = 20V rejection ratio refered VSENSE+ = 0 to 18V to output 66 dB NOTES: (a) VSENSE = "VSENSE+" - "VSENSE-" (b) Temperature dependent measurements are extracted from characterization and simulation results. Issue 2 - November 2006 © Zetex Semiconductors plc 2006 3 www.zetex.com ZXCT1051 ICC Supply Current (A) ICC Supply Current (A) Typical characteristics Supply Current v Input Voltage IS- Sense Current (A) ICC Supply Current (A) Supply Current v Supply Voltage Sense- Current v Supply Voltage IS- Sense Current (A) Percentage Change IS- (%) Supply Current v Sense Voltage Sense- Current v Temperature Issue 2 - November 2006 © Zetex Semiconductors plc 2006 Sense- Current v Sense Voltage 4 www.zetex.com ZXCT1051 10 1 ∆VOUT Output Voltage (mV) VOUT - Output Voltage (V) Typical characteristics 100m 10m 1E-3 0.01 0.1 5 0 -5 -40 -20 0 20 40 60 80 100 120 Temperature Characteristic 10.1 Incremental Gain VOUT - Output Voltage (mV) 1100 1050 1000 950 900 -20 10.0 9.9 -15 -10 -5 0 5 10 µ 15 20 0 18 16 14 12 10 8 6 4 2 0 -2 -4 -6 -8 0 2 4 6 8 10 12 14 16 18 20 Common Mode Characteristic Issue 2 - November 2006 © Zetex Semiconductors plc 2006 100m 150m Incremental Gain v Sense Voltage ∆VOUT - Output Voltage (mV) ∆VOUT - Output Voltage (mV) VOUT v Load Current 50m 12 8 4 0 -4 -8 -12 0 5 10 15 20 Supply Characteristic 5 www.zetex.com ZXCT1051 Typical characteristics 70 Supply Rejection (dB) 20 Gain (dB) 10 0 -10 -20 -30 -40 -50 -60 100 1k 10k 100k 1M 60 50 40 30 20 10 0 10M 1000 10000 100000 1E7 PSRR 1.2 90 VOUT - Output Voltage (V) Common Mode Rejection (dB) Bandwidth 1000000 80 70 60 50 40 30 20 10 0 100 1k 10k 100k 1.0 0.8 0.6 0.4 0.2 0.0 0 1M CMRR 2 4 µ 6 8 10 Large Signal Pulse Response 12 VOUT - Output Voltage (V) VOUT - Output Voltage (V) 1.02 1.00 10 0.98 0.96 0.94 0.92 0.90 0.88 0 2 4 µ 6 8 10 © Zetex Semiconductors plc 2006 6 4 2 0 0 Small Signal Pulse Response Issue 2 - November 2006 8 5 10 15 20 25 µ 30 35 40 Turn on/off Characteristic 6 www.zetex.com ZXCT1051 Application information The ZXCT1051 is Zetex’ first current monitor with a separate power supply pin. All biasing for the internal amplifiers comes from its separate VCC input and is not ‘line powered’, unlike the ZXCT1021. This means that at very small sense voltages the ZXCT1051 draws very little current (