FAN4010 High-Side Current Sensor F AN4010 — High-Side Current Sensor
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FAN4010 High-Side Current Sensor F AN4010 — High-Side Current Sensor
FAN4010 High-Side Current Sensor Features at +5V Description ■ Low cost, accurate, high-side current sensing The FAN4010 is a high-side current sense amplifier designed for battery-powered systems. Using the FAN4010 for high-side power-line monitoring does not interfere with the battery charger’s ground path. The FAN4010 is designed for portable PCs, cellular phones, and other portable systems where battery/DC power-line monitoring is critical. ■ Output voltage scaling ■ Up to 2.5V sense voltage ■ 2V to 6V supply range ■ 2μA typical offset current ■ 3.5μA quiescent current ■ -0.2% accuracy To provide a high level of flexibility, the FAN4010 functions with an external sense resistor to set the range of load current to be monitored. It has a current output that can be converted to a ground-referred voltage with a single resistor, accommodating a wide range of battery voltages and currents. The FAN4010 features allow it to be used for gas gauging as well as uni-directional or bi-directional current monitoring. ■ 6-lead MicroPak™ MLP package Applications ■ Battery chargers ■ Smart battery packs ■ DC motor control ■ Over-current monitor ■ Power management ■ Programmable current source Functional Block Diagram and Typical Circuit R sense Load VIN 100 1 VIN 2 NC VOUT Load 6 GND 5 3 IOUT NC RLoad 4 ROUT IOUT Figure 1. Functional Block Diagram and Typical Circuit Ordering Information Part Number FAN4010IL6X_F113 Package Operating Temperature Range Packaging Method MicroPak™ MLP-6 -40°C to +85°C Reel All packages are lead free per JEDEC: J-STD-020B standard. Moisture sensitivity level for all parts is MSL-1. MicroPak™ is a trademark of Fairchild Semiconductor Corporation. © 2007 Fairchild Semiconductor Corporation FAN4010 Rev. 1.0.5 www.fairchildsemi.com FAN4010 — High-Side Current Sensor February 2008 FAN4010 — High-Side Current Sensor Pin Configurations MicroPak™ MLP VIN 1 6 Load NC 2 5 GND IOUT 3 4 NC Figure 2. MicroPak™ MLP (Top View) Pin Assignments Pin # Name Description 2, 4 NC 5 GND No Connect; leave pin floating Ground 3 IOUT Output current, proportional to VIN - VLoad 1 VIN Input voltage (supply voltage) 6 Load Connection to load or battery © 2007 Fairchild Semiconductor Corporation FAN4010 Rev. 1.0.5 www.fairchildsemi.com 2 Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. Symbol Min. Max. Unit VS Supply Voltage Parameter 0 6.3 V VIN Input Voltage Range 0 6.3 V Reliability Information Symbol TJ TSTG Parameter Min. Typ. Max. Junction Temperature Storage Temperature Range TL Reflow Temperature (Soldering) θJA Resistance(1) Package Thermal -65 Unit +150 °C +150 °C +260 °C 456 °C/W Note: 1. Package thermal resistance (θJA), JEDEC standard, multi-layer test boards, still air. Electrostatic Discharge Protection Symbol ESD Standard Value HBM Human Body Model 5kV CDM Charged Device Model 1kV Recommended Operating Conditions The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to absolute maximum ratings. Symbol Parameter Max. Unit -40 +85 °C Supply Voltage Range 2 6 V Input Voltage Range 2 6 V Sensor Voltage Range, VSENSE = VIN - VLoad; ROUT = 0Ω 0 2.5 V TA Operating Temperature Range VS VIN VSENSE © 2007 Fairchild Semiconductor Corporation FAN4010 Rev. 1.0.5 Min. Typ. www.fairchildsemi.com 3 FAN4010 — High-Side Current Sensor Absolute Maximum Ratings TA = 25°C, Vs = VIN = 5V, ROUT = 100Ω, RSENSE = 100Ω, unless otherwise noted. Symbol Parameter Conditions Min. Typ. Max. Units Frequency Domain Response BWss Small Signal Bandwidth PIN = -40dBm(2), VSENSE = 10mV 600 kHz BWLs Large Signal Bandwidth PIN = -20dBm(3), VSENSE = 100mV 2 MHz Input Voltage Range VIN = Vs 2 VSENSE = 0V 0 VIN IOUT Is ISENSE Output Current (1,4) Supply Current (1) 1 6 V 9 μA VSENSE = 10mV 90 100 110 μA VSENSE = 100mV 0.975 1.000 1.025 mA VSENSE = 200mV 1.95 2.00 2.05 mA VSENSE = 1V 9.7 10.0 10.3 mA 3.5 5.0 μA VSENSE = 0V, GND pin current 2 Load Pin Input Current ACY Accuracy RSENSE = 100Ω, RSENSE = 200mV(1) Gm Transconductance IOUT /VSENSE -2.5 -0.2 10000 nA 2.5 % μA/V Notes: 1. 100% tested at 25˚C. 2. -40dBm = 6.3mVpp into 50Ω. 3. -20dBm = 63mVpp into 50Ω. 4. Includes input offset voltage contribution. © 2007 Fairchild Semiconductor Corporation FAN4010 Rev. 1.0.5 www.fairchildsemi.com 4 FAN4010 — High-Side Current Sensor Electrical Characteristics at +5V TA = 25°C, Vs = VIN = 5V, ROUT = 100Ω, RSENSE = 100Ω, unless otherwise noted. 10 250 Output Current Error (%) VS = 5V IOUT (mA) ROUT = 0Ω ROUT = 100Ω 1 VIN = 5V ROUT = 0Ω Average of 100 parts 200 150 100 +1 SIGMA 50 Average 0 -50 -1 SIGMA -100 -150 0.1 0.1 0.01 1 0.1m 1m 10m VSENSE (V) Figure 3. VSENSE vs. Output Current 10.4 Normalized Gain (dB) IOUT (mA) 3 10.0 9.8 9.6 9.4 Vs = 5V ROUT = 100Ω -20 0 20 40 60 VSENSE = 1V VSENSE = 0.1V -3 VSENSE = 0.01V -6 -9 PIN = -20dBm of VSENSE = 0.1V & 1V PIN = -40dBm of VSENSE = 0.01V 80 0.01 0.1 Temperature (°C) 1 10 Frequency (MHz) Figure 5. Output Current vs. Temperature Figure 6. Frequency Response 12 12 ROUT = 0Ω ROUT = 100Ω VSENSE = 1V 10 IOUT (mA) VSENSE = 0.4V 4 VSENSE = 0.2V 2 VSENSE = 0.8V 8 VSENSE = 0.6V 6 VSENSE = 1V 10 VSENSE = 0.8V 8 IOUT (mA) 10 0 -12 -40 1 Figure 4. Output Current Error vs. VSENSE VSENSE = 1V VIN = 5V RL= 0Ω 10.2 100m VSENSE (V) VSENSE = 0.6V 6 VSENSE = 0.4V 4 VSENSE = 0.2V 2 0 0 -2 -2 0 1 2 3 4 0 5 VIN (V) 2 3 4 5 VIN (V) Figure 7. Transfer Characteristics © 2007 Fairchild Semiconductor Corporation FAN4010 Rev. 1.0.5 1 Figure 8. Transfer Characteristics www.fairchildsemi.com 5 FAN4010 — High-Side Current Sensor Typical Performance Characteristics TA = 25°C, Vs = VIN = 5V, ROUT = 100Ω, RSENSE = 100Ω, unless otherwise noted. 0 2.5 CMRR (dB) -20 Output Current Error (%) VIN = 5V PIN = -20dBm ROUT = 100Ω -10 -30 -40 VSENSE = 100mV -50 -60 VSENSE = 10mV -70 VSENSE = 1mV -80 -90 0.00001 0.0001 VSENSE = 200mV ROUT = 0Ω Average of 100 parts 2.0 1.5 +1 SIGMA 1.0 Average 0.5 0 -0.5 -1 SIGMA -1.0 -1.5 -2.0 -2.5 0.001 0.01 0.1 1 10 2.0 Frequency (MHz) 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 VIN (V) Figure 9. CMRR vs. Frequency Figure 10. VIN vs. Output Current Error 6.0 VIN = 5V ROUT = 100Ω 5.5 5.0 Is (μA) 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 VSENSE (V) Figure 11. Supply Current vs. VSENSE © 2007 Fairchild Semiconductor Corporation FAN4010 Rev. 1.0.5 www.fairchildsemi.com 6 FAN4010 — High-Side Current Sensor Typical Performance Characteristics (Continued) Detailed Description The FAN4010 measures the voltage drop (V SENSE) across an external sense resistor located in the high voltage side of the circuit. V SENSE is converted to a linear current via an internal operational amplifier and precision 100Ω resistor. The value of this current is V SENSE/100Ω (internal). Output current flows from the IOUT pin to an external resistor R OUT to generate an output voltage proportional to the current flowing to the load. INPUT 0.3in COPPER VSENSE = ILoad • R SENSE (1) VOUT = 0.01 x VSENSE x ROUT (2) VOUT 0.3in COPPER 0.1in COPPER V IN Load 6 2 NC GND 5 NC 4 1 Use the following equations to scale a load current to an output voltage: LOAD RSENSE 3 IOUT ROUT Load 6 Rsense 3 IOUT 100 VIN 1 + Vsense Figure 13. Using PCB Trace for RSENSE RLoad VIN Selecting ROUT R OUT can be chosen to obtain the output voltage range required for the particular downstream application. For example, if the output of the FAN4010 is intended to drive an analog-to-digital convertor (ADC), R OUT should be chosen such that the expected full-scale output current produces an input voltage that matches the input range of the ADC. For instance, if expected loading current ranges from 0 to 1A, a R SENSE resistor of 1Ω produces an output current that ranges from 0 to 10mA. If the input voltage range of the ADC is 0 to 2V, a R OUT value of 200Ω should be used. VOUT R OUT Figure 12. Functional Circuit Selecting RSENSE Selection of RSENSE is a balance between desired accuracy and allowable voltage loss. Although the FAN4010 is optimized for high accuracy with low VSENSE values, a larger RSENSE value provides additional accuracy. However, larger values of RSENSE create a larger voltage drop, reducing the effective voltage available to the load. This can be troublesome in low-voltage applications. Because of this, the maximum expected load current and allowable load voltage should be well understood. Although higher values of VSENSE can be used, RSENSE should be chosen to satisfy the following condition: 10mV < VSENSE < 200mV The input voltage and full-scale output current (IOUT_ FS) needs to be taken into account when setting up the output range. To ensure sufficient operating headroom, choose: (R OUT • IOUT_FS) such that VIN - VSENSE - (ROUT • IOUT_FS) > 1.6V Output current accuracy for the recommended V SENSE levels between 10mV and 200mV are typically much better than 1%. As a result, the absolute output voltage accuracy is dependent upon the precision of the output resistor. (3) For low-cost applications where accuracy is not as important, a portion of the printed circuit board (PCB) trace can be used as an R SENSE resistor. Figure 13 shows an example of this configuration. The resistivity of a 0.1 inch wide trace of two-ounce copper is about 30mΩ/ft. Unfortunately, the resistance temperature coefficient is relatively large (approximately 0.4% / C), so systems with a wide temperature range may need © 2007 Fairchild Semiconductor Corporation FAN4010 Rev. 1.0.5 (4) Make sure the input impedance of the circuit connected to VOUT is much higher than ROUT to ensure accurate V OUT values. Since the FAN4010 provides a trans-impedance function, it is ideal for applications involving current rather than voltage sensing. www.fairchildsemi.com 7 FAN4010 — High-Side Current Sensor to compensate for this effect. Additionally, self heating due to load currents introduces a nonlinearity error. Care must be taken not to exceed the maximum power dissipation of the copper trace. Application Information 2X 0.05 C 1.45 B 2X (1) 0.05 C (0.49) 5X 1.00 (0.75) (0.52) 1X A TOP VIEW 0.55MAX (0.30) 6X PIN 1 0.05 C 0.05 0.00 RECOMMENED LAND PATTERN 0.05 C C 0.25 0.15 6X 1.0 DETAIL A 0.10 0.05 0.45 0.35 0.10 0.00 6X C B A C 0.40 0.30 0.35 5X 0.25 0.40 5X 0.30 0.5 (0.05) 6X Notes: BOTTOM VIEW (0.13) 4X 0.075 X 45 CHAMFER DETAIL A PIN 1 TERMINAL 1. CONFORMS TO JEDEC STANDARD M0-252 VARIATION UAAD 2. DIMENSIONS ARE IN MILLIMETERS 3. DRAWING CONFORMS TO ASME Y14.5M-1994 MAC06AREVC Figure 14. 6-Lead MicroPak™ Molded Leadless Package (MLP) Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/ © 2007 Fairchild Semiconductor Corporation FAN4010 Rev. 1.0.5 www.fairchildsemi.com 8 FAN4010 — High-Side Current Sensor Mechanical Dimensions FAN4010 — High-Side Current Sensor © 2007 Fairchild Semiconductor Corporation FAN4010 Rev. 1.0.5 www.fairchildsemi.com 9