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MPY100
MULTIPLIER-DIVIDER
FEATURES
q LOW COST q DIFFERENTIAL INPUT q ACCURACY 100% TESTED AND GUARANTEED q NO EXTERNAL TRIMMING REQUIRED q LOW NOISE: 90µVrms, 10Hz to 10kHz q HIGHLY RELIABLE ONE-CHIP DESIGN q DIP OR TO-100 TYPE PACKAGE q WIDE TEMPERATURE OPERATION
APPLICATIONS
q MULTIPLICATION q DIVISION q q q q q q SQUARING SQUARE ROOT LINEARIZATION POWER COMPUTATION ANALOG SIGNAL PROCESSING ALGEBRAIC COMPUTATION
q TRUE RMS-TO-DC CONVERSION
DESCRIPTION
The MPY100 multiplier-divider is a low cost precision device designed for general purpose application. In addition to four-quadrant multiplication, it also performs analog square root and division without the bother of external amplifiers or potentiometers. Lasertrimmed one-chip design offers the most in highly reliable operation with guaranteed accuracies. Because of the internal reference and pretrimmed accuracies the MPY100 does not have the restrictions of other low cost multipliers. It is available in both TO-100 and DIP ceramic packages.
X1 V-I X2 Multiplier Core Y1 V-I Y2 A Out
Z1 V-I Z2 Attenuator
High Gain Output Amplifier
International Airport Industrial Park • Mailing Address: PO Box 11400 Tel: (520) 746-1111 • Twx: 910-952-1111 • Cable: BBRCORP •
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• Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd. • Tucson, AZ 85706 Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
1987 Burr-Brown Corporation
PDS-412D
Printed in U.S.A. March, 1995
SPECIFICATIONS
At TA = +25°C and ±VS = 15VDC, unless otherwise specified. MPY100A PARAMETER CONDITIONS MIN TYP MAX MIN MPY100B/C TYP */* MAX MIN MPY100S TYP * MAX UNITS
MULTIPLIER PERFORMANCE Transfer Function Total Error Initial vs Temperature vs Temperature vs Supply(1) Individual Errors Output Offset Initial vs Temperature vs Temperature vs Supply(1) Scale Factor Error Initial vs Temperature vs Temperature vs Supply(1) Nonlinearity X Input Y Input Feedthrough X Input Y Input vs Temperature vs Temperature vs Supply(1) –10V ≤ X, Y ≤ 10V TA = +25°C –25°C ≤ TA ≤ +85°C –55°C ≤ TA ≤ +125°C
(X1 – X2)(Y1 –Y2) 10
+ Z2 ±2.0 ±0.05
±0.017 ±0.05
±1.0/0.5 ±0.008/0.008 ±0.02/0.02 */*
±0.5 ±0.025 * ±0.05
% FSR % FSR/°C % FSR/°C % FSR/%
TA = +25°C –25°C ≤ TA ≤ +85°C –55°C ≤ TA ≤ +125°C TA = +25°C –25°C ≤ TA ≤ +85°C –55°C ≤ TA ≤ +125°C X = 20Vp-p; Y = ±10VDC Y = 20Vp-p: X = ±10VDC f = 50Hz X = 20Vp-p; Y = 0 Y = 20Vp-p; X = 0 –25°C ≤ TA ≤ +85°C –55°C ≤ TA ≤ 125°C
±50 ±0.7 ±0.25 ±0.12 ±0.008 ±0.05 ±0.08 ±0.08 100 6 0.1 0.15
±100 ±2.0
±10/7 ±0.7/0.3 */* */* */* */* */* */* 30/30 */* */* */* */*
±50/25 ±2.0/±0.7
±7 ±0.3 * * ±0.008 * * * 30 * 0.1 * *
±50 ±0.7
mV mV/°C mV/°C mV/% % FSR % FSR/°C % FSR/°C % FSR % % FSR % FSR mVp-p mVp-p mVp-p/°C mVp-p/°C mVp-p/%
DIVIDER PERFORMANCE Transfer Function Total Error (with external adjustments)
X1 > X2 X = 10V –10V ≤ Z ≤ +10V X = 1V –1V ≤ Z ≤ +1V +0.2V ≤ X ≤ +10V –10V ≤ Z ≤ +10V
10(Z2 – Z1) (X1 – X2) ±1.5 ±4.0 ±5.0 (X1 – X2)2 10 ±1.2
+ Y1
±0.75/0.35 ±2.0/1.0 ±2.5/1.0 */*
±0.35 ±1.0 ±1.0 *
% FSR % FSR % FSR
SQUARER PERFORMANCE Transfer Function
+ Z2
Total Error
–10V ≤ X ≤ +10V
±0.6/0.3 */* ±1/0.5 */* */* */* */* */* */* */*
±0.3 * ±0.5 * * * * * * *
% FSR
SQUARE ROOTER PERFORMANCE Transfer Function Z 1 < Z2 Total Error 1V ≤ Z ≤ 10V AC PERFORMANCE Small-Signal Bandwidth % Amplitude Error % (0.57°) Vector Error Full Power Bandwidth Slew Rate Settling Time Overload Recovery
+√10(Z2 – Z1) + X2 ±2 550 70 5 320 20 2 0.2
% FSR kHz kHz kHz kHz V/µs µs µs
Small-Signal Small-Signal |VO| = 10V, RL = 2kΩ |VO| = 10V, RL = 2kΩ ε = ±1%, ∆VO = 20V 50% Output Overload
INPUT CHARACTERISTICS Input Voltage Range Rated Operation Absolute Maximum Input Resistance Input Bias Current
±10 X, Y, Z(2) X, Y, Z 10 1.4
*/* ±VCC */* */* */*
* * * *
V V MΩ µA
OUTPUT CHARACTERISTICS Rated Output Voltage IO = ±5mA Current VO = ±10V Output Resistance f = DC
±10 ±5 1.5
*/* */* */*
* * *
V mA Ω
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MPY100
2
SPECIFICATIONS
PARAMETER OUTPUT NOISE VOLTAGE fO = 1Hz fO = 1kHz l/f Corner Frequency fB = 5Hz to 10kHz fB = 5Hz to 5MHz
(CONT)
MPY100A MPY100B/C MAX MIN TYP */* */* */* */* */* */* ±20 */* */* +85 +125 +150 */* */* */* */* */* */* –55 * * */* * * +125 * * MAX MIN MPY100S TYP * * * * * * * MAX UNITS µV/√Hz µV/√Hz Hz µVrms mVrms VDC VDC mA °C °C °C
At TA = +25°C and ±VS = 15VDC, unless otherwise specified.
CONDITIONS X=Y=0
MIN
TYP 6.2 0.6 110 60 1.3 ±15 ±5.5
POWER SUPPLY REQUIREMENTS Rated Voltage Operating Range Derated Performance Quiescent Current TEMPERATURE RANGE (Ambient) Specification Operating Range Derated Performance Storage
±8.5
–25 –55 –65
* Same as MPY100A specification. */* B/C grades same as MPY100A specification. NOTES: (1) Includes effects of recommended null pots. (2) Z2 input resistance is 10MΩ, typical, with VOS pin open. If VOS pin is grounded or used for optional offset adjustment, the Z2 input resistance may be as low as 25kΩ
PIN CONFIGURATIONS
Top View Z1 Out –VCC NC NC NC X1 1 2 3 4 5 6 7 14 +VCC 13 Y1 12 Y2 11 VOS 10 Z2 9 8 X2 NC DIP Top View TO-100
Y2 Y1 +VCC Z1 2 3 Out 4 5 –VCC
NOTES: (1) VOS adjustment optional not normally recommended. VOS pin may be left open or grounded. (2) All unused input pins should be grounded. NOTES: (1) VOS adjustment optional not normally recommended. VOS pin may be left open or grounded. (2) All unused input pins should be grounded.
10 1 9
VOS 8 7 Z2 X2
6
X1
ORDERING INFORMATION ABSOLUTE MAXIMUM RATINGS
Supply ........................................................................................... ±20VDC Internal Power Dissipation(1) .......................................................... 500mW Differential Input Voltage(2) ........................................................... ±40VDC Input Voltage Range(2) ................................................................. ±20VDC Storage Temperature Range ......................................... –65°C to +150°C Operating Temperature Range .................................... –55°C to +125°C Lead Temperature (soldering, 10s) ............................................... +300°C Output Short-circuit Duration(3) ................................................ Continuous Junction Temperature .................................................................... +150°C NOTES: (1) Package must be derated on θJC = 15° C/W and θJA = 165° C/W for the metal package and θJC = 35 ° C/W and θJA = 220° C/ W for the ceramic package. (2) For supply voltages less than ±20VDC, the absolute maximum input voltage is equal to the supply voltage. (3) Short-circuit may be to ground only. Rating applies to +85°C ambient for the metal package and +65° C for the ceramic package. MODEL MPY100AG MPY100AM MPY100BG MPY100BM MPY100CG MPY100CM MPY100SG MPY100SM PACKAGE 14-Pin Ceramic DIP Metal TO-100 14-Pin Ceramic DIP Metal TO-100 14-Pin Ceramic DIP Metal TO-100 14-Pin Ceramic DIP Metal TO-100 TEMPERATURE RANGE –25°C to +85°C –25°C to +85°C –25°C to +85°C –25°C to +85°C –25°C to +85°C –25°C to +85°C –55°C to +125°C –55°C to +125°C
PACKAGE INFORMATION
MODEL MPY100AG MPY100AM MPY100BG MPY100BM MPY100CG MPY100CM MPY100SG MPY100SM PACKAGE 14-Pin Ceramic DIP Metal TO-100 14-Pin Ceramic DIP Metal TO-100 14-Pin Ceramic DIP Metal TO-100 14-Pin Ceramic DIP Metal TO-100 PACKAGE DRAWING NUMBER(1) 169 007 169 007 169 007 169 007
NOTE: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix D of Burr-Brown IC Data Book.
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3
MPY100
SIMPLIFIED SCHEMATIC
+VCC
A Z2 Out
25kΩ X1 X2 Y2 Y1
3.8kΩ
Z1
25kΩ
25kΩ
25kΩ
25kΩ
25kΩ
25kΩ
25kΩ
VOS 500µA –VCC 500µA 500µA
CONNECTION DIAGRAM
+15VDC
X1 X2
+VS
Z1 VO Out
Y1 Y2 VOS
(1)
–VS
Z2
(X1 – X2)(Y1 – Y2) 10
NOTE: (1) Optional component. 100kΩ –15VDC
DICE INFORMATION
PAD 1 2 3 4 5 6 7 8 9 10 Substrate Bias: –VCC FUNCTION Y2 VOS Z2 X2 X1 VO Z1 +V –V Y1
MECHANICAL INFORMATION
MILS (0.001") Die Size Die Thickness Min. Pad Size Backing 107 x 93 ±5 20 ±3 4x4 MILLIMETERS 2.72 x 2.36 ±0.13 0.51 ±0.08 0.10 x 0.10 Gold
MPY100 DIE TOPOGRAPHY
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MPY100
4
TYPICAL PERFORMANCE CURVES
At TA = +25°C and ±VS = 15VDC, unless otherwise specified.
TOTAL ERROR vs AMBIENT TEMPERATURE
NONLINEARITY vs FREQUENCY 100 Input Signal = 20Vp-p
Nonlinearity (% of FSR)
Magnitude of Total Output Error (% of FSR)
10
10
1
X
1
0.1
Y
0.01 0.001
0.1 –100 –50 0 50 100 150 Ambient Temperature (°C)
10
100
1k
10k
100k
1M
Frequency (Hz)
FEEDTHROUGH vs FREQUENCY 1000 5
OUTPUT AMPLITUDE vs FREQUENCY Small Signal
Feedthrough Voltage (mVp-p)
500 200 100 50 20 10 5 10 100 1k 10k 100k 1M 10M Frequency (Hz) Y Feedthrough –20 10k 100k Frequency (Hz) 1M X Feedthrough
Output Amplitude (dB)
Input Signal = 20Vp-p
0
–5 X –10 Y –15
10M
LARGE SIGNAL RESPONSE 10 Input Output Output Voltage (V) 5 20 18 16
INPUT VOLTAGE FOR LINEAR RESPONSE Positive Common-Mode Differential Negative Common-Mode
Input Range (V)
3 4 5
14 12 10 8 6 4 2 0
0 RL = 2kΩ CL = 150pF
–5
–10 0 1 2 Time (µs)
0
2
4
6
8
10
12
14
16
18
20
Power Supply Voltage (±VCC)
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5
MPY100
TYPICAL PERFORMANCE CURVES (CONT)
At TA = +25°C and ±VS = 15VDC, unless otherwise specified.
COMMON-MODE REJECTION vs FREQUENCY 80 70 60 X = 12Vp-p Y = ±10VDC Y = 12Vp-p X = ±10VDC
OUTPUT VOLTAGE vs OUTPUT CURRENT 25 +25°C –55°C 20 VCC = ±20V VCC = ±15V VCC = ±10V
Output Voltage (±V)
CMR (dB)
15
50 40 30 20 10 100 1k 10k 100k 1M 10M Frequency (Hz)
10
5 0 0
VCC = ±8.5V
2
4
6
8
10
12
14
16
Output Current (±mA)
SUPPLY CURRENT vs AMBIENT TEMPERATURE 16 14
Supply Current (mA)
12 10 8 6 4 2 0 –100 –50 0 50 100 150 Ambient Temperature (°C) Quiescent 5mA Load
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MPY100
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THEORY OF OPERATION
The MPY100 is a variable transconductance multiplier consisting of three differential voltage-to-current converters, a multiplier core and an output differential amplifier as illustrated in Figure 1. The basic principle of the transconductance multiplier can be demonstrated by the differential stage in Figure 2. For small values of the input voltage, V1, that are much smaller than VT, the transistor’s thermal voltage, the differential output voltage, VO, is: VO = gm RLV1 The transconductance gm of the stage is given by: gm = IE/VT
and is modulated by the voltage, V2, to give gm ≈ V2/VTRE Substituting this into the original equation yields the overall transfer function VO = gmRLV1 = V1V2 (RL/VTRE) which shows the output voltage to be the product of the two input voltages, V1 and V2. Variations in IE due to V2 cause a large common-mode voltage swing in the circuit. The errors associated with this common-mode voltage can be eliminated by using two differential stages in parallel and cross-coupling their outputs as shown in Figure 3.
+VS
RL
Stable Reference and Bias VO = A X1 V-I X2 Multiplier Core Y1 V-I Y2 A Out +VS –VS (X1 – X2)(Y1 – Y2) 10
RL + VO –
I1
– (Z1 – Z2)
I2 Q2 Q3
I3
I4 Q4
+ V1 –
Q1
Transfer Function
Q5 + V2
High Gain Output Amplifier
RE
RE
Q6
Z1 V-I Z2 Attenuator
– IT –VCC
FIGURE 1. MPY100 Functional Block Diagram.
FIGURE 3. Cross-Coupled Differential Stages as a VariableTransconductance Multiplier. An analysis of the circuit in Figure 3 shows it to have the same overall transfer function as before: VO = V1V2 (RL/VTRE). For input voltages larger than VT, the voltage-to-current transfer characteristics of the differential pair Q1, Q2 or Q3 and Q4 are no longer linear. Instead, their collector currents are related to the applied voltage V1 I1 I2 = I3 I4
V1
+VCC I1 RL RL I2
– VO + + V1 – Q3 Q1 Q2
=e
VT
+ V2 –
RE
IE
The resultant nonlinearity can be overcome by developing V1 logarithmically to exactly cancel the exponential relationship just derived. This is done by diodes D1 and D2 in Figure 4. The emitter degeneration resistors, RX and RY, in Figure 4, provide a linear conversion of the input voltages to differential current, IX and IY, where:
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FIGURE 2. Basic Differential Stage as a Transconductance Multiplier.
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MPY100
IX = VX/RX and IY = VY/RY Analysis of Figure 4 shows the voltage VA to be: VA = (2RL/I1)(IXIY) Since IX and IY are linearly related to the input voltages VX and VY, VA may also be written: VA = KVXVY where K is a scale factor. In the MPY100, K is chosen to be 0.1. The addition of the Z input alters the voltage VA to: VA = KVXVY – VZ Therefore, the output of the MPY100 is: VO = A[KVXVY – VZ] where A is the open-loop gain of the output amplifier. Writing this last equation in terms of the separate inputs to the MPY100 gives VO = A (X1 – X2)(Y1 – Y2) 10 – (Z1 – Z2)
CAPACITIVE LOADS Stable operation is maintained with capacitive loads to 1000pF in all modes, except the square root mode for which 50pF is a safe upper limit. Higher capacitive loads can be driven if a 100Ω resistor is connected in series with the MPY100’s output.
DEFINITIONS
TOTAL ERROR (Accuracy) Total error is the actual departure of the multiplier output voltage form the ideal product of its input voltages. It includes the sum of the effects of input and output DC offsets, gain error and nonlinearity. OUTPUT OFFSET Output offset is the output voltage when both inputs VX and VY are 0V. SCALE FACTOR ERROR Scale factor error is the difference between the actual scale factor and the ideal scale factor. NONLINEARITY Nonlinearity is the maximum deviation from a best straightline (curve fitting on input-output graph) expressed as a percent of peak-to-peak full scale output. FEEDTHROUGH Feedthrough is the signal at the output for any value of VX or VY within the rated range, when the other input is zero.
the transfer function of the MPY100. WIRING PRECAUTIONS In order to prevent frequency instability due to lead inductance of the power supply lines, each power supply should be bypassed. This should be done by connecting a 10µF tantalum capacitor in parallel with a 1000pF ceramic capacitor from the +VCC and –VCC pins of the MPY100 to the power supply common. The connection of these capacitors should be as close to the MPY100 as practical.
+VCC
RCM
RL
RL + VA – A
I4 D1 D2 + V1 – I1 Q1 Q2 I2 I3 Q3 Q4
VO Out
X1 + VX – X2 RX 2
Q7
Q8 RX 2 RY 2
Q5
Q6 + RY 2
Y1 RZ 2
Q9
Q10 RZ 2
Z1 + VZ –
VY – Y2
Z2 211
211
211
–VCC
FIGURE 4. MPY100 Simplified Circuit Diagram.
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MPY100
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SMALL SIGNAL BANDWIDTH Small signal bandwidth is the frequency at which the output is down 3dB from its low-frequency value for nominal output amplitude of 10% of full scale. 1% AMPLITUDE ERROR The 1% amplitude error is the frequency the output amplitude is in error by 1%, measured with an output amplitude of 10% of full scale. 1% VECTOR ERROR The 1% vector error is the frequency at which a phase error of 0.01 radians (0.57°) occurs. This is the most sensitive measure of dynamic error of a multiplier.
VX, ±10V, FS
εDIVIDER = 10 εMULTIPLIER/(X1 – X2) It is obvious from this error equation that divider error becomes excessively large for small values of X1 – X2. A 10to-1 denominator range is usually the practical limit. If more accurate division is required over a wide range of denominator voltages, an externally generated voltage may be
VO = X1 X2 MPY100 Y1 VY, ±10V, FS Y2 –VCC VOS
(1)
(X1 – X2)(Y1 – Y2) 10
+ Z2
Z1 VO, ±10V, FS Out Z2 Optional Summing Input, ±10V, FS
+VCC
TYPICAL APPLICATIONS
MULTIPLICATION Figure 5 shows the basic connection for four-quadrant multiplication. The MPY100 meets all of its specifications without trimming. Accuracy can, however be improved over a limited range by nulling the output offset voltage using the 100Ω optional balance potentiometer shown in Figure 5. AC feedthrough may be reduced to a minimum by applying an external voltage to the X or Y input as shown in Figure 6. Z2, the optional summing input, may be used to sum a voltage into the output of the MPY100. If not used, this terminal, as well as the X and Y input terminals, should be grounded. All inputs should be referenced to power supply common. Figure 7 shows how to achieve a scale factor larger than the nominal 1/10. In this case, the scale factor is unity which makes the transfer function VO = KVXVY = K(X1 – X2)(Y1 – Y2).K =
1 + (R1/R2) 10
100kΩ –15VDC +15VDC
NOTE: (1) Optional balance potentiometer.
FIGURE 5. Multiplier Connection.
+VCC 50kΩ 470kΩ 1kΩ –VCC To the appropriate input terminal.
FIGURE 6. Optional Trimming Configuration.
R2 10kΩ X1 X2 MPY100 Y1 Y2 Z2 Out R1 90kΩ VO
Z1
0.1 ≤ K ≤ 1
This circuit has the disadvantage of increasing the output offset voltage by a factor of 10, which may require the use of the optional balance control as in Figure 1 for some applications. In addition, this connection reduces the small signal bandwidth to about 50kHz. DIVISION Figure 8 shows the basic connection for two-quadrant division. This configuration is a multiplier-inverted analog divider, i.e., a multiplier connected in the feedback loop of an operational amplifier. In the case of the MPY100, this operational amplifier is the output amplifier shown in Figure 1. The divider error with a multiplier-inverted analog divider is approximately: 9
FIGURE 7. Connection for Unity Scale Factor.
10(Z2 – Z1) (X1 – X2)
VO =
+ Y1
VXDemonimator ±0.2V to +10V, FS Optional Summing Input, ±10V, FS
X1 X2 MPY100 Y1 Y2 Z2
Z1 Out V2
VO = ±10V, FS
Numerator ±10V, FS
FIGURE 8. Divider Connection.
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MPY100
applied to the unused X-input (see Optional Trim Configuration). To trim, apply a ramp of +100mV to +1V at 100Hz to both X1 and Z1 if X2 is used for offset adjustment, otherwise reverse the signal polarity and adjust the trim voltage to minimize the variation in the output. An alternative to this procedure would be to use the Burr-Brown DIV100, a precision log-antilog divider. SQUARING
VO = (X1 – X2)2 10 + Z2
MORE CIRCUITS The theory and procedures for developing virtually any function generator or linearization circuit can be found in the Burr-Brown/McGraw Hill book “FUNCTION CIRCUITS Design and Applications.”
VO = + 10(Z2 – Z1) +X2 Optional Summing Input, ±10V, FS X1 X2 MPY100 Y1 Y2 Z2 VZ (a) Circuit for positive VZ. +0.2V ≤ (Z2 – Z1) ≤ +10V Out RL
Z1
VO
X1 X2 MPY100 Y1 VX ±10V, FS Y2 Z2
Z1 Out
VO = ±10V, FS
Optional Summing Input, ±10V, FS
FIGURE 9. Squarer Connection. SQUARE ROOT Figure 10 shows the connection for taking the square root of the voltage VZ. The diode prevents a latching condition which could occur if the input momentarily changed polarity. This latching condition is not a design flaw in the MPY100, but occurs when a multiplier is connected in the feedback loop of an operational amplifier to perform square root functions. The load resistance, R L, m ust be in the range of 10kΩ ≤ RL ≤ 1MΩ. This resistance must be in the circuit as it provides the current necessary to operate the diode.
Optional Summing Input, ±10V, FS
VO = – 10(Z2 – Z1) +X2 X1 X2 MPY100 Y1 Y2 Z2 VZ Out RL
Z1
VO
(b) Circuit for negative VZ.
+0.2V ≤ (Z2 – Z1) ≤ +10V
FIGURE 10. Square Root Connection.
(V2 – V1) V1
VO =
100
1% per volt V1
PERCENTAGE COMPUTATION The circuit of Figure 11 has a sensitivity of 1V/% and is capable of measuring 10% deviations. Wider deviation can be measured by decreasing the ratio of R2/R1. BRIDGE LINEARIZATION The use of the MPY100 to linearize the output from a bridge circuit makes the output VO independent of the bridge supply voltage. See Figure 12.
+0.2V ≤ V1 ≤ +10V
X1 X2 MPY100 Y1 Y2 Z2
Z1 Out
VO
9kΩ
V2 1kΩ
FIGURE 11. Percentage Computation. TRUE RMS-TO-DC CONVERSION The rms-to-DC conversion circuit of Figure 13 gives greater accuracy and bandwidth but with less dynamic range than most rms-to-DC converters. SINE FUNCTION GENERATOR The circuit in Figure 14 uses implicit feedback to implement the following sine function approximation: VO = (1.5715V1 – 0.004317V13)/(1 + 0.001398V12) = 10 sin (9V1)
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MPY100
10
V R + ∆R R
RG 40kΩ X1 V1 INA101 G=2 R R V2 X2 MPY100 Y1 Y2 Z2 R1 Out Z1 Z1 VO
V1 =
V 2
1 2R 1+ ∆R
V2 = V
1 2R 1+ ∆R
VO = 5
R1 + R2 ∆R R R2
R2
NOTE: V should be as large as possible to minimize divider errors. But V ≤ [10 + (20R/∆R)] to keep V2 within the input voltage limits of the MPY100.
FIGURE 12. Bridge Linearization.
Matched to 0.025% 20kΩ R1 10kΩ R2 10kΩ
OPA111 VIN (±5V pk) 10µF DC 10kΩ X1 X2 MPY100 Y1 Y2 Z2 OPA111 10MΩ 10kΩ AC Out
Z1
10kΩ C2 10µF VO VO = VIN2 0 to 5V
Mode Switch
+VS 50kΩ Zero Adjust 20kΩ –VS
FIGURE 13. True RMS-to-DC Conversion.
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MPY100
23.165kΩ
71.548kΩ
10kΩ
X1 X2 MPY100 Y1 Y2 Z2
Z1 Out
VO = 10 sin 9V1
5.715kΩ
V1 X1 X2 MPY100 Y1 Y2 Z2 Out Z1
10kΩ
(–10V ≤ V1 ≤ +10V, and 1V = 9°)
FIGURE 14. Sine Function Generator
ei(t) = 2 Eirms Sin ωt iL(t) = 2 ILrms Sin (ωt + θ ) ei R1 R2 R4 ∝e i
IL Load
R5
∝ =R5/(R4 +R5) X R3 γiL Y XY 10 γ =(–R1R3)/R2 Instantaneous Power
Real Power (∝γ/10)(EirmsILrms cosθ )
FIGURE 15. Single-Phase Instantaneous and Real Power Measurement.
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant any BURR-BROWN product for use in life support devices and/or systems.
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MPY100
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