lmp8358mtx National Semiconductor Corporation, lmp8358mtx Datasheet
lmp8358mtx
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lmp8358mtx Summary of contents
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... Other features that make the LMP8358 a versatile solution for many applications are its rail-to-rail output, low input voltage noise and high gain-bandwidth product. Typical Application LMP ® registered trademark of National Semiconductor Corporation. © 2010 National Semiconductor Corporation LMP8358 Features Typical Values unless otherwise noted, T ■ ...
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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. ESD Tolerance (Note 2) Human Body Model Machine Model Charge Device V Differential (V − +IN ...
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Symbol Parameter e Input Voltage Noise n I Input Current Noise Density n G Gain Error E G Gain Error E G Gain Error Contribution from Chip E Gain Error Temperature Coefficient NL Non-Linearity GBW Gain Bandwidth BW −3 dB ...
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Symbol Parameter V Output Voltage Swing High OUT Output Voltage Swing Low I Output Current Sourcing OUT Output Current Sinking I Supply Current S T Turn-on time from Shutdown SD_ON PS Prescaler Error (Offset + Gain Error) E Prescaler Gain ...
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Symbol Parameter PSRR Power supply Rejection Ratio EMIRR Electro Magnetic Interference Rejection Ratio Z Differential Input Impedance INDM Z Common Mode Input Impedance INCM V Differential Mode Input Voltage INDM I Input Bias Current B I Input Offset Current OS ...
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Symbol Parameter BW −3 dB Bandwidth SR Slew Rate (Note 7) t 0.01% Settling Time s V Output Voltage Swing High OUT Output Voltage Swing Low I Output Current Sourcing OUT Output Current Sinking I Supply Current S T Turn-on ...
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Symbol Parameter I Fault Detection: Test Current TEST Electrical Characteristics (Serial Interface) Unless otherwise specified, all limits guaranteed for T (VHSER/VLPAR) − (VLSER/VHPAR) Symbol Parameter V Input Logic Low Threshold IL V Input Logic High Threshold IH V Output Logic ...
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... CSB/SHDN SCK/G2 SDI/G1 SDO/G0 Ordering Information Package Part Number LMP8358MA 14-Pin SOIC LMP8358MAX LMP8358MT 14-Pin TSSOP LMP8358MTX www.national.com at the temperature extremes by the total temperature change. OS 14-Pin SOIC/ 14-Pin TSSOP 30045402 Top View Communication Mode Serial Positive Input Negative Input Reference Sense ...
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Block Diagram 14-Pin SOIC/ 14-Pin TSSOP 9 30045406 www.national.com ...
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Timing Diagrams www.national.com SPI Timing Diagram 30045453 Timing Diagram Test Circuit 10 30045403 ...
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Typical Performance Characteristics Gain vs. Frequency for Various COMP Settings Gain vs. Frequency for Various COMP Settings Gain vs. Frequency for Various Cap Loads 3.3V and T = 25°C unless otherwise noted. A Gain vs. Frequency for ...
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Gain Error vs. Common Mode Voltage, V Gain Error Distribution, Gain = 100 Distribution www.national.com = 3.3V Gain Error Distribution, Gain = 10 300454f5 = 3.3V Gain Error Distribution, Gain = 1000 ...
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TCV Distribution 3. 300454g7 300454e5 300454e7 TCV Distribution vs ...
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V vs REF CMRR vs. Frequency Voltage Noise vs. Time www.national.com = 3.3V S 300454g9 300454d8 300454d2 14 CMRR vs. Frequency 300454d3 PSRR vs. Frequency 300454d9 Voltage Noise vs. Frequency 300454c9 ...
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Small Signal Step Response for Various COMP Settings Large Signal Step Response for Various COMP Settings Positive Overshoot vs. C Small Signal Step Response for Various COMP Settings 300454d4 Large Signal Step Response for Various COMP Settings 300454d6 Supply Current ...
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Input Bias Current vs. V THD+N vs. Frequency I vs. V TEST1 www.national.com , 300454f0 300454e0 CM 300454g0 16 Input Bias Current vs 5. 300454f1 THD+N vs. V OUT ...
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I vs. V TEST3 CM 300454f8 I vs. V TEST5 CM 300454f6 Output Swing Low vs. Supply Voltage 300454f3 I vs. V TEST4 CM Output Swing High vs. Supply Voltage EMIRR IN+ vs. Frequency 17 300454f7 300454f2 300454e1 www.national.com ...
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Application Information INTRODUCTION The LMP8358 is a precision programmable gain instrumen- tation amplifier. Its gain can be programmed to 10, 20, 50, 100, 200, 500 or 1000 through an SPI-compatible serial in- terface or through a parallel interface. Alternatively, its ...
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FIGURE 1. (A) Communication with LMP8358 in Parallel Mode (B) Communication with LMP8358 in Serial Mode Communication Mode Selection The interface mode is determined by the two interface level pins VLSER/VHPAR and VHSER/VLPAR. VLSER/VHPAR < VHSER/ Serial VLPAR Logic low ...
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Table 3. Function of Digital IO Pins, Serial Mode Pin Name Description SDO Serial Data Out SDI Serial Data In SCK Serial Clock CSB Chip Select VLSER Negative Logic level VHSER Positive Logic Level Table 4. LMP8358 Register Description, Serial ...
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Star Configuration The configuration shown in Figure 3 LMP8358 will always have the same value in each register. FIGURE 3. Star Configuration for Writing the Same Value Into Each Register FIGURE 4. Star Configuration for Writing Different Values Into Each ...
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The following two examples show how the registers are writ- ten in the Daisy Chain Configuration. Tabel 5. If all three LMP8358s need a gain of 100 with a compensation level of 010. (0000 0000 0001 0011) Register of LMP8358 ...
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Frequency Compensation (Serial) The gain-bandwidth compensation is set to one of five levels under program control. The amount of compensation can be decreased to maximize the available bandwidth as the gain of the amplifier is increased. The compensation level is ...
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When MUX[1:0] = 01b and POL = 1b both inputs are connected to the -IN pin of the LMP8358. The +IN pin is left floating. Compare Input to V- When MUX[1:0] = 10b or 11b one external input of ...
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FAULT DETECTION METHODS Using the Multiplexer, Polarity, and Current features the end user can detect faults in the system between the sensor and the LMP8358. These examples will use the set up shown in FIGURE 7. Bridge Connected to the ...
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Open Input Figure 9 shows an example of an open input fault. To sense this type of fault use the 1/50 feature by setting MUX[1:0] to 10b to test the +IN pin or to 11b to test the −IN pin, ...
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Shorted Inputs Figure 11 shows the inputs of the LMP8358 shorted. To detect this fault set CUR[2:0] = 101b to inject a 100µA current and set the gain to 10× (5000x). The LMP8358 is set up with nor- mal differential ...
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Fault Detection Example Using the fault detection features of the LMP8358 an end product, such as a scale, can periodically test that no damage has occurred to the system. A routine can be written that could, for example, run on ...
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START UP AND POWER ON RESET During power on, 50µs after V + − V − > 1V the LMP8358 resets the internal register to 0000x. If the digital supplies and inputs are undefined after the Power On Reset transients ...
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www.national.com 30 ...
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Physical Dimensions inches (millimeters) unless otherwise noted 14-Pin SOIC NS Package Number M14A 14–Pin TSSOP NS Package Number M14MT 31 www.national.com ...
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... National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. ...