ZXCT1030 HIGH-SIDE CURRENT MONITOR WITH COMPARATOR DESCRIPTION APPLICATIONS The ZXCT1030 is a high side current sense monitor containing an internal reference and comparator with a non-latching output. Using this device eliminates the need to disrupt the ground plane when sensing a load current. • Battery chargers • Electronic fuse • DC motor control • Over current monitor The wide input voltage range of 20V down to as low as 2.2V make it suitable for a range of applications. Dynamics and supply current are optimised for the processing of fast pulses, associated with switch mode applications. • Power management • Inrush current limiting FUNCTIONAL BLOCK DIAGRAM FEATURES • Low cost, accurate high-side current sensing. • Output voltage scaling. Vin Rsense sense+ • Up to 18V output. Vcc To load sense- Current Monitor 5V Vcomp_supply • 2.2V – 20V supply range. Vout Rcomp • 270A quiescent current. + Comp_in • 1.5% typical accuracy. Comp_out - Vref_out • MSOP8 Package. • Voltage reference on chip ZXCT1030 • Comparator on chip ORDERING INFORMATION Device Reel size Tape width Quantity per reel ZXCT1030X8TA 7” 12mm 500 units ZXCT1030X8TC 13” 12mm 2500 units DEVICE MARKING • ZXCT 1030 PROVISIONAL ISSUE J - MAY 2004 1 SEMICONDUCTORS ZXCT1030 Absolute Maximum Ratings Voltage on any pin Operating Temperature Storage Temperature Package Power Dissipation MSOP8 -0.6V and Vcc +0.6V -40 to 85°C -55 to 125°C (TA = 25°C) 500mW ELECTRICAL CHARACTERISTICS Test Conditions TA = 25°C, Vin = Vcc = 15V SYMBOL PARAMETER CONDITIONS LIMITS Min Typ UNIT Max V CC V CC Range 2.2 20 V sense+ Sense+ range 2.2 V CC V out Output Voltage V sense V sense V sense V sense V sense V sense R out Output resistance V sense- = 15V, V out = 1V V out V out TC temperature coefficient I CC Supply current I sense+ Sense+ input current I sense- Sense- input current V sense V cm 3 2 = = = = = = 0V 10mV 30mV 50mV 100mV 500mV V sense- = 14.9V Sense Voltage Common Mode Range 0 88 284 480 970 4500 2 100 300 500 1000 5000 10 112 316 520 1030 5500 mV mV mV mV mV mV 1.2 1.5 1.8 K⍀ 30 V sense- = 15V ppm/⬚C 170 270 350 µA 25 48 90 µA 25 70 220 nA 500 mV 0 V cc = 15V V 2.8 V V comp_supply = 5V V comp_in = V ref V sense = 10mV 2 Acc Accuracy V sense = 100mV -3 Gain V out / V sense V sense = 100mV 9.7 BW Bandwidth 3 10.0 % 10.3 V sense = 10mVp-p 3 MHz V sense = 100mVp-p 6 MHz Vsense = (Vsense +) - (Vsense -) 3 Level of Vin where comparator output defaults to ‘off’. PROVISIONAL ISSUE J - MAY 2004 SEMICONDUCTORS 2 ZXCT1030 Absolute Maximum Ratings Voltage on any pin Operating Temperature Storage Temperature Package Power Dissipation MSOP8 -0.6V and Vcc +0.6 V -40 to 85°C -55 to 125°C (TA = 25°C) 500mW ELECTRICAL CHARACTERISTICS (Cont.) Test Conditions TA = 25°C, Vin = Vcc = 15V SYMBOL PARAMETER CONDITIONS LIMITS Min Typ UNIT Max Comparator Vcomp Input Voltage 0.005 VH Hysteresis V comp_supply = 5V R comp = 10k IB Input Bias V comp_supply = 5V V comp- in = 1V R comp = 10k TD Propagation Delay V comp_supply = 5V R comp = 10k V OL Output Voltage Low V comp_supply = 5V R comp = 10k V OH Output Voltage High V comp_supply = 5V R comp = 10k I OL Output Sink Current V OL = 0.4V I OH Output High Leakage Current V comp_supply = 5V R comp = 10K 10 15 5 50 mV 100 100 30 150 V nA ns 200 V comp_ mV V supply 2 mA 1.0 µA Voltage Reference V ref delta V ref Reference Current = 0A Reference Current = -300A Reference Current = +5A Change in Vref Isource 5A to Isink 300A TC PSR Supply rejection 1.200 1.240 1.280 V 1.200 1.240 1.280 V 1.200 1.240 1.280 V 10 mV 30 ppm/⬚C 0.01 %/V PROVISIONAL ISSUE J - MAY 2004 3 SEMICONDUCTORS ZXCT1030 TYPICAL CHARACTERISTICS PROVISIONAL ISSUE J - MAY 2004 SEMICONDUCTORS 4 ZXCT1030 Voltage output Current Monitor Comparator Referring to the block diagram, the current monitor takes the small voltage developed across the sense resistor (Vsense) and transfers it from the large common mode supply voltage to a ground-referenced signal with a gain of 10. The sense input common mode range is 2.2V to 20V. In this range, a linear output voltage is delivered. The open collector output is active low and is asserted when Vsense x 10 (Vout) > Vcomp_in. It can be connected to any voltage rail up to Vin via a pull-up resistor. Suggest values for the resistor are in the range of 10-100k⍀. In the case where high load currents or a short circuit occurs, thus reducing the common mode signals (V+, V-) typically below 2.2V, the comparator will default to the asserted state. This can eliminate a closed loop system ‘latch-up’ condition, allowing the controller to remove the applied power. Reference The bandgap reference allows the comparator to compare the translated Vsense with threshold value chosen by the user which can be any voltage from 0 to 1.24V, configured by two external resistors which forms Vcomp_in. Stability The output current which can be drawn from the comparator reference (Iref source) is limited to 5µA, making potentiometers ≥ 250k⍀ suitable for setting a threshold level. Where a lower potentiometer resistor value is used, an additional resistor value should be inserted between Vref and Vcc to maintain sufficient current for the reference. (as shown in figure 1.0). To ensure stable operation of the ZXCT1030, it is recommended a decoupling capacitor is placed across the VCC and ground connections. A ceramic 10F will be adequate. FIGURE 1.0 External resistor for reference level PIN CONNECTIONS MSOP8 Vcc 1 Sense- 2 8 Vout 6 Vref_out 7 Sense+ 3 5 Comp_in GND 4 The Voltage reference has a maximum current sink capability. This magnitude of current will be influenced by the value of R1 which is inserted between Vref and Vcc. The value of current flowing through R1 can be expressed as: I = (Vcc -Vref) / R1 Comp_out Pin Name Pin Function Vcc Supply voltage Sense- Negative sense input Sense+ Positive sense input GND Ground Comp_in Comparator input, usually a ratio of the reference or other control signal. Vref_out Reference output Vout Current Monitor output voltage Comp_out Open collector comparator output PROVISIONAL ISSUE J - MAY 2004 5 SEMICONDUCTORS ZXCT1030 PACKAGE DIMENSIONS PACKAGE DIMENSIONS DIM D 6 5 2 3 4 E H 8 7 1 eX6 θ A A1 C Inches MIN MAX MIN MAX A - 1.10 - 0.043 A1 0.05 0.15 0.002 0.006 B 0.25 0.40 0.010 0.016 C 0.13 0.23 0.005 0.009 D 2.90 3.10 0.114 0.122 e B Millimetres 0.65 BSC 0.0256 BSC L E H PAD LAYOUT DETAILS 2.90 3.10 4.90 BSC 0.114 0.122 0.193 BSC L 0.40 0.70 0.016 0.028 ° 0° 6° 0° 6° © Zetex Semiconductors plc 2004 Europe Americas Asia Pacific Corporate Headquaters Zetex GmbH Streitfeldstraße 19 D-81673 München Germany Zetex Inc 700 Veterans Memorial Hwy Hauppauge, NY 11788 USA Zetex (Asia) Ltd 3701-04 Metroplaza Tower 1 Hing Fong Road, Kwai Fong Hong Kong Zetex Semiconductors plc Zetex Technology Park, Chadderton Oldham, OL9 9LL United Kingdom Telefon: (49) 89 45 49 49 0 Fax: (49) 89 45 49 49 49 [email protected] Telephone: (1) 631 360 2222 Fax: (1) 631 360 8222 [email protected] Telephone: (852) 26100 611 Fax: (852) 24250 494 [email protected] Telephone (44) 161 622 4444 Fax: (44) 161 622 4446 [email protected] These offices are supported by agents and distributors in major countries world-wide. This publication is issued to provide outline information only which (unless agreed by the Company in writing) may not be used, applied or reproduced for any purpose or form part of any order or contract or be regarded as a representation relating to the products or services concerned. The Company reserves the right to alter without notice the specification, design, price or conditions of supply of any product or service. For the latest product information, log on to www.zetex.com PROVISIONAL ISSUE J - MAY 2004 SEMICONDUCTORS 6