FEATURES ±4 V human body model (HBM) ESD High common-mode voltage range V to +6 V operating 3 V to +68 V survival Buffered output voltage Wide operating temperature range 8-Lead SOIC: 4 C to + C Excellent ac and dc performance 6 μv/ C typical offset drift 8 ppm/ C typical gain drift db typical CMRR at dc Qualified for automotive applications APPLICATIONS High-side current sensing Motor controls Transmission controls Engine management Suspension controls Vehicle dynamic controls DC to dc converters High Voltage, Current Shunt Monitor FUNCTIONAL BLOCK DIAGRAM IN+ A IN PROPRIETARY OFFSET CIRCUITRY GND Figure. G = + V+ OUT 73- GENERAL DESCRIPTION The is a high voltage, precision current shunt monitor. It features a set gain of V/V, with a maximum ±.3% gain error over the entire temperature range. The buffered output voltage directly interfaces with any typical converter. Excellent common-mode rejection from V to +6 V is independent of the V supply. The performs unidirectional current measurements across a shunt resistor in a variety of industrial and automotive applications, such as motor controls, solenoid controls, or battery management. Special circuitry is devoted to output linearity being maintained throughout the input differential voltage range of mv to mv, regardless of the common-mode voltage present. The has an operating temperature range of 4 C to + C and is offered in a small 8-lead SOIC package. Rev. B Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 96, Norwood, MA 6-96, U.S.A. Tel: 78.39.47 8 6 Analog Devices, Inc. All rights reserved. Technical Support www.analog.com
TABLE OF CONTENTS Features... Applications... Functional Block Diagram... General Description... Revision History... Specifications... 3 Absolute Maximum Ratings... 4 ESD Caution... 4 Pin Configuration and Function Descriptions... Typical Performance Characteristics... 6 Theory of Operation... Data Sheet Application Notes... Output Linearity... Applications Information... High-Side Current Sensing with a Low-Side Switch... High-Side Current Sensing... Low-Side Current Sensing... Outline Dimensions... 3 Ordering Guide... 3 Automotive Products... 3 REVISION HISTORY /6 Rev. A to Rev. B Changes to Features Section and Applications Section... Changes to Figure 3... / Rev. to Rev. A Change to Applications Section... Updated Outline Dimensions... 3 Changes to Ordering Guide... 3 Added Automotive Products Section... 3 /8 Revision : Initial Version Rev. B Page of 3
SPECIFICATIONS Operating temperature range (TOPR) = 4 C to + C, ambient temperature (TA) = C, VS = V, RL = kω (RL is the output load resistor), unless otherwise noted. Table. Parameter Min Typ Max Unit Test Conditions/Comments GAIN Initial V/V Accuracy ±. % Output voltage (VO). V dc, TA Accuracy Over Temperature ±.3 % TOPR Drift 8 ppm/ C TOPR VOLTAGE OFFSET Offset Voltage, Referred to Input (RTI) ± mv TA Over Temperature (RTI) ±. mv TOPR Drift +6 +8 µv/ C TOPR INPUT Input Impedance Differential kω Common Mode MΩ Common-mode voltage > V 3. kω Common-mode voltage < V Common-Mode Input Voltage Range +6 V Common-mode continuous Differential Input Voltage Range mv Differential input voltage Common-Mode Rejection Ratio db TOPR, f = dc to khz, VCM > V 8 9 db TOPR, f = dc to 4 khz, VCM < V OUTPUT Output Voltage Range Low.3 V TA. V TOPR Output Voltage Range High 4.9 V TA 4.9 V TOPR Output Impedance Ω DYNAMIC RESPONSE Small Signal 3 db Bandwidth 4 khz TOPR Slew Rate 4. V/µs TA NOISE. Hz to Hz, RTI 7 µv p-p Spectral Density, khz, RTI 7 nv/ Hz POWER SUPPLY Operating Range 4.. V Quiescent Current Over Temperature.3. ma VCM > V, TOPR Power Supply Rejection Ratio 7 db TOPR TEMPERATURE RANGE For Specified Performance 4 + C When the common-mode input voltage is less than V, the supply current increases, which can be calculated by IS =.7 (VCM) +.. Rev. B Page 3 of 3
Data Sheet ABSOLUTE MAXIMUM RATINGS Table. Parameter Supply Voltage Continuous Input Voltage (Survival) Continuous Differential Input Voltage Reverse Supply Voltage ESD Rating HBM Charged Device Model (CDM) Operating Temperature Range Storage Temperature Range Output Short-Circuit Duration Rating. V 3 V to +68 V. V.3 V ±4 V ± V 4 C to + C 6 C to + C Indefinite ESD CAUTION Stresses at or above those listed under Absolute Maximum Ratings may cause permanent damage to the product. This is a stress rating only; functional operation of the product at these or any other conditions above those indicated in the operational section of this specification is not implied. Operation beyond the maximum operating conditions for extended periods may affect product reliability. Rev. B Page 4 of 3
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS 8 6 Figure. Metallization Diagram 73- IN GND NC 3 NC 4 TOP VIEW (Not to Scale) NC = NO CONNECT 8 7 6 +IN NC V+ OUT Figure 3. Pin Configuration 73-3 Table 3. Pin Function Descriptions Pin No. Mnemonic X Y Description IN 8 +9 Inverting Input GND 73 Ground 3, 4, 7 NC Not applicable Not applicable No Connect OUT +6 466 Buffered Output 6 V+ +73 66 Supply 8 +IN +9 +9 Noninverting Input Rev. B Page of 3
TYPICAL PERFORMANCE CHARACTERISTICS V OSI (mv)...8.6.4...4.6.8.. 4 4 6 8 TEMPERATURE ( C) Figure 4. Typical Offset Drift (VOSI) vs. Temperature 73-7 GAIN (db) Data Sheet 4 3 3 3 3 4 k k M M FREQUENCY (Hz) Figure 7. Typical Small Signal Bandwidth (VOUT = mv p-p) 73-8 4 3 9 CMRR (db) 9 8 COMMON-MODE VOLTAGE >V COMMON-MODE VOLTAGE <V TOTAL OUTPUT ERROR (%) 8 7 6 4 3 7 6 k k k M FREQUENCY (Hz) Figure. Typical CMRR vs. Frequency 73-4 3 3 4 4 6 6 7 7 8 8 9 9 DIFFERENTIAL INPUT VOLTAGE (mv) Figure 8. Total Output Error vs. Differential Input Voltage 73-48 GAIN ERROR (ppm) INPUT BIAS CURRENT (µa) 49 3 4 6 V IN+ V IN 4 4 6 8 TEMPERATURE ( C) Figure 6. Typical Gain Error vs. Temperature 73-6 7 7 7 DIFFERENTIAL INPUT VOLTAGE (mv) Figure 9. Input Bias Current vs. Differential Input Voltage, VCM = V 73-7 Rev. B Page 6 of 3
INPUT BIAS CURRENT (µa) 9 8 7 6 IN+ IN mv/div V/DIV INPUT OUTPUT 4 7 7 DIFFERENTIAL INPUT VOLTAGE (mv) Figure. Input Bias Current vs. Differential Input Voltage, VCM = V 73-6 TIME (4ns/DIV) Figure 3. Fall Time 73-.8 INPUT BIAS CURRENT (ma).4.4.8..6 mv/div V/DIV INPUT OUTPUT..4 4 4 6 8 6 INPUT COMMON-MODE VOLTAGE (V) Figure. Input Bias Current vs. Input Common-Mode Voltage 73-4 TIME (4ns/DIV) Figure 4. Rise Time 73-4. 3. mv/div SUPPLY CURRENT (ma) 3... V/DIV INPUT.. 4 4 6 8 6 INPUT COMMON-MODE VOLTAGE (V) Figure. Supply Current vs. Input Common-Mode Voltage 73- TIME (µs/div) OUTPUT Figure. Differential Overload Recovery (Falling) 73-3 Rev. B Page 7 of 3
Data Sheet INPUT mv/div V/DIV TIME (µs/div) OUTPUT 73-4 MAXIMUM OUTPUT SINK CURRENT (ma) 9 8 7 6 4 4 6 8 4 TEMPERATURE ( C) 73- Figure 6. Differential Overload Recovery (Rising) Figure 9. Maximum Output Sink Current vs. Temperature V/DIV.%/DIV TIME (4µs/DIV) 73-9 MAXIMUM OUTPUT SOURCE CURRENT (ma) 9 8 7 6 4 4 4 6 8 4 TEMPERATURE ( C) 73- Figure 7. Settling Time (Falling) Figure. Maximum Output Source Current vs. Temperature. V/DIV.%/DIV OUTPUT VOLTAGE RANGE (V) 4.6 4. 3.8 3.4 3..6..8 TIME (4µs/DIV) Figure 8. Settling Time (Rising) 73-.4. 3 4 6 7 8 9 OUTPUT SOURCE CURRENT (ma) Figure. Output Voltage Range vs. Output Source Current 73-8 Rev. B Page 8 of 3
. 4 OUTPUT VOLTAGE RANGE (V).6..8.4 COUNT 8 9 6 3 3 4 6 7 8 9 OUTPUT SINK CURRENT (ma) Figure. Output Voltage Range from GND vs. Output Sink Current 73-9 6 4 8 6 4 GAIN DRIFT (ppm/ C) Figure 4. Gain Drift Distribution 73-3 3 3 + C + C 4 C 6 4 COUNT COUNT 8 6 4 V OS (mv) 73- OFFSET DRIFT (µv/ C) 73-3 Figure 3. Offset Distribution (VOS) Figure. Offset Drift Rev. B Page 9 of 3
THEORY OF OPERATION In typical applications, the amplifies a small differential input voltage generated by the load current flowing through a shunt resistor. The rejects high common-mode voltages (up to 6 V) and provides a ground-referenced, buffered output that interfaces with an analog-to-digital converter (ADC). Figure 6 shows a simplified schematic of the. I IN R I SHUNT R SHUNT A R PROPRIETARY OFFSET CIRCUITRY V+ Data Sheet A load current flowing through the external shunt resistor produces a voltage at the input terminals of the. R and R connect the input terminals to A. The inverting terminal, which has very high input impedance, is held to (VCM) (ISHUNT RSHUNT) because negligible current flows through R. A forces the noninverting input to the same potential. Therefore, the current that flows through R is equal to IIN = (ISHUNT RSHUNT)/R This current (IIN) is converted back to a voltage via ROUT. The output buffer amplifier has a gain of V/V and offers excellent accuracy as the internal gain setting resistors are precision trimmed to within.% matching. The resulting output voltage is equal to OUT = (ISHUNT RSHUNT) R OUT G = + OUT = (I SHUNT R SHUNT ) GND Figure 6. Simplified Schematic 73- Rev. B Page of 3
APPLICATION NOTES OUTPUT LINEARITY In all current sensing applications, and especially in automotive and industrial environments where the common-mode voltage can vary significantly, it is important that the current sensor maintain the specified output linearity, regardless of the input differential or common-mode voltage. The contains specific circuitry on the input stage, which ensures that even when the differential input voltage is very small and the common-mode voltage is also low (below the V supply), the input-to-output linearity is maintained. Figure 7 shows the differential input voltage vs. the corresponding output voltage at different common modes. Regardless of the common mode, the provides a correct output voltage when the differential input is at least mv, which is due to the voltage range of the output amplifier that can go as low as 33 mv typical. The specified minimum output amplifier voltage is mv to provide sufficient guardbands. The ability of the to work with very small differential inputs, regardless of the common-mode voltage, allows more dynamic range, accuracy, and flexibility in any current sensing application. 8 6 OUTPUT VOLTAGE (mv) 4 8 6 4 IDEAL V OUT (mv) V OUT (mv) @ V CM =V V OUT (mv) @ V CM =6V 3 4 6 7 8 9 DIFFERENTIAL INPUT VOLTAGE (mv) Figure 7. Gain Linearity due to Differential and Common-Mode Voltage 73-6 Rev. B Page of 3
Data Sheet APPLICATIONS INFORMATION HIGH-SIDE CURRENT SENSING WITH A LOW-SIDE SWITCH In such load control configurations, the PWM-controlled switch is ground referenced. An inductive load (solenoid) is tied to a power supply. A resistive shunt is placed between the switch and the load (see Figure 8). An advantage of placing the shunt on the high side is that the entire current, including the recirculation current, can be measured because the shunt remains in the loop when the switch is off. In addition, diagnostics can be enhanced because shorts to ground can be detected with the shunt on the high side. In this circuit configuration, when the switch is closed, the common-mode voltage moves down to near the negative rail. When the switch is opened, the voltage reversal across the inductive load causes the common-mode voltage to be held one diode drop above the battery by the clamp diode. OVERCURRENT DETECTION (<ns) OUT NC 4 V 6 7 8 GND NC IN AD84 V REG +IN V S 3 6 7 8 OUT V+ NC IN+ NC NC GND IN 4 3 SHUNT CLAMP DIODE INDUCTIVE LOAD BATTERY V BATTERY INDUCTIVE LOAD CLAMP DIODE SWITCH SHUNT Figure 8. Low-Side Switch 8 7 6 IN+ NC V+ OUT IN GND NC NC 4 3 4 HIGH-SIDE CURRENT SENSING In this configuration, the shunt resistor is referenced to the battery. High voltage is present at the inputs of the current sense amplifier. In this mode, the recirculation current is again measured and shorts to ground can be detected. When the shunt is battery referenced, the produces a linear ground-referenced analog output. An AD84 can also provide an overcurrent detection signal in as little as ns (see Figure 9). This feature is useful in high current systems where fast shutdown in overcurrent conditions is essential. 73-7 SWITCH Figure 9. Battery-Referenced Shunt Resistor LOW-SIDE CURRENT SENSING In systems where low-side current sensing is preferred, the provides an integrated solution with great accuracy. Ground noise is rejected, CMRR is typically higher than 9 db, and output linearity is not compromised, regardless of the input differential voltage. V 6 7 8 OUT V+ NC IN+ NC NC GND IN 4 3 INDUCTIVE LOAD CLAMP DIODE SHUNT SWITCH BATTERY 73-8 Figure 3. Ground-Referenced Shunt Resistor 73-9 Rev. B Page of 3
OUTLINE DIMENSIONS. (.968) 4.8 (.89) 4. (.74) 3.8 (.497) 8 4 6. (.44).8 (.84). (.98). (.4) COPLANARITY. SEATING PLANE.7 (.) BSC.7 (.688).3 (.3). (.).3 (.) 8. (.98).7 (.67). (.96). (.99).7 (.).4 (.7) 4 COMPLIANT TO JEDEC STANDARDS MS--AA CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. Figure 3. 8-Lead Standard Small Outline Package [SOIC_N] Narrow Body (R-8) Dimensions shown in millimeters and (inches) 47-A ORDERING GUIDE Model, Temperature Range Package Description Package Option YRZ 4 C to + C 8-Lead Standard Small Outline Package [SOIC_N] R-8 YRZ-RL 4 C to + C 8-Lead Standard Small Outline Package [SOIC_N], 3 Tape and Reel R-8 YRZ-R7 4 C to + C 8-Lead Standard Small Outline Package [SOIC_N], 7 Tape and Reel R-8 WYRZ 4 C to + C 8-Lead Standard Small Outline Package [SOIC_N] R-8 WYRZ-R7 4 C to + C 8-Lead Standard Small Outline Package [SOIC_N], 7 Tape and Reel R-8 WYRZ-RL 4 C to + C 8-Lead Standard Small Outline Package [SOIC_N], 3 Tape and Reel R-8 Z = RoHS Compliant Part. W = Qualified for Automotive Applications. AUTOMOTIVE PRODUCTS The WYRZ models are available with controlled manufacturing to support the quality and reliability requirements of automotive applications. Note that these automotive models may have specifications that differ from the commercial models; therefore designers should review the Specifications section of this data sheet carefully. Only the automotive grade products shown are available for use in automotive applications. Contact your local Analog Devices account representative for specific product ordering information and to obtain the specific Automotive Reliability reports for these models. 8 6 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D73--/6(B) Rev. B Page 3 of 3