The MPY634 is a wide bandwidth, high accuracy, fourquadrant analog multiplier. Its accurately laser-trimmed
multiplier characteristics make it easy to use in a wide
variety of applications with a minimum of external parts,
often eliminating all external trimming. Its differential X, Y,
and Z inputs allow configuration as a multiplier, squarer,
divider, square-rooter, and other functions while maintaining high accuracy.
The wide bandwidth of this new design allows signal
processing at IF, RF, and video frequencies. The internal
output amplifier of the MPY634 reduces
design complexity compared to other high frequency multipliers and balanced modulator circuits. It is
capable of performing frequency mixing, balanced modulation, and demodulation with excellent carrier rejection.
An accurate internal voltage reference provides
precise setting of the scale factor. The differential Z input
allows user-selected scale factors from 0.1 to 10 using
external feedback resistors.
+V
S
–V
S
X
1
X
2
Y
1
Y
2
Z
1
Z
2
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
* Specification same as for MPY634AM.
Gray indicates obsolete parts.
NOTES: (1) Figures given are percent of full scale, ±10V (i.e., 0.01% = 1mV). (2) May be reduced to 3V using external resistor between –V
component due to nonlinearity; excludes effect of offsets.
* Specification same as for MPY634AM/BM.
NOTE: Gray indicates obsolete parts.
OBSOLETEOBSOLETE
S
**
1
1
2
Input
NC
NC
Input
Input
NC
1
2
3
4
5
6
7
8
SOIC: MPY634KUDIP: MPY634KP
X
14
+V
S
13
NC
12
Output
11
Z
Input
1
10
Z
Input
2
9
NC
8
–V
S
X2 Input
Scale Factor
Y
Y
16
+V
S
15
NC
14
Output
13
Z
Input
1
12
Z
Input
2
11
NC
10
–V
S
9
NC
ORDERING INFORMATION
Basic Model Number
Performance Grade
K: U: –40°C to +85°C
Package Code
P: Plastic 14-pin DIP
U: 16-pin SOIC
NOTE: (1) Performance grade identifier may not be marked on the SOIC
package; a blank denotes “K” grade.
(1)
MPY634( )( )
PACKAGE INFORMATION
PRODUCTPACKAGENUMBER
MPY634KP14-Pin PDIP010
MPY634KU16-Pin SOIC211
NOTE: (1) For the most current package and ordering information, see the
Package Option Addendum located at the end of this data sheet.
(1)
PACKAGE DRAWING
MPY634
SBFS017A
www.ti.com
3
TYPICAL PERFORMANCE CURVES
At TA = +25°C, VS = ±15VDC, unless otherwise noted.
–20
FEEDTHROUGH vs FREQUENCY
–40
X Feedthrough
–60
Y Feedthrough
–80
Feedthrough Attenuation (dB)
–100
1001k10k1M10M100M
100k
Frequency (Hz)
COMMON-MODE REJECTION RATIO vs FREQUENCY
90
80
70
60
Typical for all inputs
50
40
CMRR (dB)
30
20
10
0
100100M
10k1M10M
Frequency (Hz)
10
FREQUENCY RESPONSE AS A MULTIPLIER
Normal Connection
0
CL = 0pF
–10
With X10 Feedback
–20
Output Response (dB)
Attenuator
–30
1k10k100k1M10M100M
Frequency (Hz)
FEEDTHROUGH vs TEMPERATURE
–50
–60
fY = 500kHz
V
= nulled
X
–70
nulled at 25°C
Feedthrough Attenuation (dB)
–80
–60
–202060100140–4004080120
Temperature (°C)
C
= 1000pF
L
NOISE SPECTRAL DENSITY
1.5
1.25
1
0.75
Noise Spectral Density (µV/√Hz)
0.5
1010010k100k
vs FREQUENCY
1k
Frequency (Hz)
4
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60
FREQUENCY RESPONSE AS A DIVIDER
VX = 100mVDC
V
= 10mVrms
40
(dB)
2
/V
0
20
Output, V
Z
= 1VDC
V
X
V
= 100mVrms
Z
= 10VDC
V
X
V
= 100mVrms
Z
0
–20
1k10k100k1M10M100M
Frequency (Hz)
MPY634
SBFS017A
TYPICAL PERFORMANCE CURVES (CONT)
TA = +25°C, VS = ±15VDC, unless otherwise noted.
INPUT/OUTPUT SIGNAL RANGE
14
12
Output, RL ≥ 2kΩ
10
8
6
Peak Positive or Negative Signal (V)
4
81012161820
vs SUPPLY VOLTAGES
All inputs, SF = 10V
14
Positive or Negative Supply (V)
THEORY OF OPERATION
The transfer function for the MPY634 is:
V
OUT
where:
A = open-loop gain of the output amplifier (typically
85dB at DC).
SF = Scale Factor. Laser-trimmed to 10V but adjustable
over a 3V to 10V range using external resistors.
X, Y, Z are input voltages. Full-scale input voltage
is equal to the selected SF. (Max input voltage =
±1.25 SF).
An intuitive understanding of transfer function can be gained
by analogy to the op amp. By assuming that the open-loop
gain, A, of the output operational amplifier is infinite,
MPY634
SBFS017A
(X1 – X2) (Y1 – Y2)
= A – (Z1 – Z2)
SF
www.ti.com
inspection of the transfer function reveals that any V
OUT
can
be created with an infinitesimally small quantity within the
brackets. Then, an application circuit can be analyzed by
assigning circuit voltages for all X, Y and Z inputs and
setting the bracketed quantity equal to zero. For example,
the basic multiplier connection in Figure 1, Z1 = V
OUT
and
Z2 = 0. The quantity within the brackets then reduces to:
(X1 – X2) (Y1 – Y2)
– (V
SF
OUT
– 0) = 0
This approach leads to a simple relationship which can be
solved for V
to provide the closed-loop transfer function.
OUT
The scale factor is accurately factory adjusted to 10V and is
typically accurate to within 0.1% or less. The scale factor
may be adjusted by connecting a resistor or potentiometer
between pin SF and the –VS power supply. The value of the
external resistor can be approximated by:
5
RSF = 5.4kΩ
SF
10 – SF
Internal device tolerances make this relationship accurate to
within approximately 25%. Some applications can benefit
from reduction of the SF by this technique. The reduced
input bias current, noise, and drift achieved by this technique
can be likened to operating the input circuitry in a higher
gain, thus reducing output contributions to these effects.
Adjustment of the scale factor does not affect bandwidth.
The MPY634 is fully characterized at V
= ±15V but
S
operation is possible down to ±8V with an attendant reduction of input and output range capability. Operation at
voltages greater than ±15V allows greater output swing to be
achieved by using an output feedback attenuator (Figure 1).
As with any wide bandwidth circuit, the power supplies
should be bypassed with high frequency ceramic capacitors.
These capacitors should be located as near as practical to the
power supply connections of the MPY634. Improper bypassing can lead to instability, overshoot, and ringing in the
output.
X Input
±10V FS
±12V PK
Y Input
±10V FS
±12V PK
+V
X
1
X
Out
2
MPY634
SFZ
Y
1
Y
–V
2
+15V
S
1
Z
2
–15V
S
10kΩ
V
, ±12V PK
OUT
= (X
– X2) (Y1 – Y2)
1
(Scale = 1V)
90kΩ
Optional
Peaking
Capacitor
C
= 200pF
F
FIGURE 1. Connections for Scale-Factor of Unity.
BASIC MULTIPLIER CONNECTION
Figure 2 shows the basic connection as a multiplier. Accuracy is fully specified without any additional user-trimming
circuitry. Some applications can benefit from trimming of
one or more of the inputs. The fully differential inputs
facilitate referencing the input quantities to the source voltage common terminal for maximum accuracy. They also
allow use of simple offset voltage trimming circuitry as
shown on the X input.
The differential Z input allows an offset to be summed in
V
. In basic multiplier operation, the Z2 input serves as
OUT
the output voltage ground reference and should be connected
to the ground of the driven system for maximum accuracy.
A method of changing (lowering) SF by connecting to the
SF pin was discussed previously. Figure 1 shows an alternative method of changing the effective SF of the overall
circuit by using an attenuator in the feedback connection to
Z1. This method puts the output amplifier in a higher gain
and is thus accompanied by a reduction in bandwidth and an
+15V
V
OUT
– X2) (Y1 – Y2)
(X
1
=
–15V
, ±12V PK
10V
Optional
Summing
Z, ±10V PK
+ Z2
Input,
+15V
50kΩ
–15V
Optional Offset
Trim Circuit
X Input
±10V FS
±12V PK
470kΩ
Y Input
±10V FS
±12V PK
1kΩ
+V
X
1
X
Out
2
MPY634
SFZ
Y
1
Y
–V
2
S
1
Z
2
S
FIGURE 2. Basic Multiplier Connection.
increase in output offset voltage. The larger output offset
may be reduced by applying a trimming voltage to the high
impedance input, Z
.
2
The flexibility of the differential Z inputs allows direct
conversion of the output quantity to a current. Figure 3
shows the output voltage differentially-sensed across a series resistor forcing an output-controlled current. Addition
of a capacitor load then creates a time integration function
useful in a variety of applications such as power computation.
X Input
±10V FS
±12V PK
Y Input
±10V FS
±12V PK
+V
X
1
X
Out
2
MPY634
SFZ
Y
1
Y
–V
2
S
1
Z
2
S
+15V
I
=
OUT
– X2) (Y1 – Y2)
(X
1
x
10V
Current
Sensing
Resistor,
R
, 2kΩ
–15V
S
min
1
R
S
Integrator
Capacitor
(see text)
FIGURE 3. Conversion of Output to Current.
SQUARER CIRCUIT (FREQUENCY DOUBLER)
Squarer, or frequency doubler, operation is achieved by
paralleling the X and Y inputs of the standard multiplier
circuit. Inverted output can be achieved by reversing the
differential input terminals of either the X or Y input.
Accuracy in the squaring mode is typically a factor of two
better than the specified multiplier mode with maximum
error occurring with small (less than 1V) inputs. Better
accuracy can be achieved for small input voltage levels by
reducing the scale factor, SF.
DIVIDER OPERATION
The MPY634 can be configured as a divider as shown in
Figure 4. High impedance differential inputs for the numerator and denominator are achieved at the Z and X inputs,
Hello
6
www.ti.com
MPY634
SBFS017A
respectively. Feedback is applied to the Y2 input, and Y1 is
g
normally referenced to output ground. Alternatively, as the
transfer function implies, an input applied to Y1 can be
summed directly into V
. Since the feedback connection
OUT
is made to a multiplying input, the effective gain of the
output op amp varies as a function of the denominator input
voltage. Therefore, the bandwidth of the divider function is
proportional to the denominator voltage (see Typical Performance Curves).
Output, ±12V PK
+15V
V
= + Y1
OUT
Z Input
(Numerator)
±10V FS,
±12V PK
10V(Z
(X1 – X2)
2
– Z1)
X Input
(Denominator)
0.1V ≤ X ≤ 10V
Optional
Summing Input
±10V PK
+
–
+V
X
1
X
Out
2
MPY634
SFZ
Y
1
S
1
Z
2
+15V
+V
X
Optional
Summing
Input, X,
±10V PK
1
X
2
SFZ
Y
1
Y
2
MPY634
Out
–V
S
1
Z
2
S
Z Input
10V FS
12V PK
–15V
FIGURE 5. Square-Rooter Connection.
APPLICATIONS
Output, ±12V PK
V
= 10V(Z2 – Z1) + X
OUT
Reverse
this and
X inputs
for
Negative
Outputs
R
L
(Must be
provided)
2
Y
–V
2
S
–15V
FIGURE 4. Basic Divider Connection.
Accuracy of the divider mode typically ranges from 1.0% to
2.5% for a 10 to 1 denominator range depending on device
grade. Accuracy is primarily limited by input offset voltages
and can be significantly improved by trimming the offset of
the X input. A trim voltage of ±3.5mV applied to the “low
side” X input (X2 for positive input voltages on X1) can
produce similar accuracies over 100 to 1 denominator range.
To trim, apply a signal which varies from 100mV to 10V at
a low frequency (less than 500Hz). An offset sine wave or
ramp is suitable. Since the ratio of the quantities should be
constant, the ideal output would be a constant 10V. Using
AC coupling on an oscilloscope, adjust the offset control for
minimum output voltage variation.
SQUARE-ROOTER
A square-rooter connection is shown in Figure 5. Input
voltage is limited to one polarity (positive for the connection
shown). The diode prevents circuit latch-up should the input
go negative. The circuit can be configured for negative input
and positive output by reversing the polarity of both the X
and Y inputs. The output polarity can be reversed by reversing the diode and X input polarity. A load resistance of
approximately 10kΩ must be provided. Trimming for improved accuracy would be accomplished at the Z input.
A sin (2π 10MHz t)
B sin (2π 10MHz t + )
Multiplier connection followed by a low-pass filter forms phase
detector useful in phase-locked-loop circuitry. R
PLL circuitry to provide desired loop-dampin
θ
+V
X
1
X
2
MPY634
SFZ
Y
1
Y
–V
2
Out
S
1
Z
2
S
+15V
1kΩ
–15V
X
characteristics.
FIGURE 6. Phase Detector.
+15V
–15V
+
E
C
–
2kΩ2kΩ
+
E
S
–
+V
X
1
X
2
MPY634
SFZ
Y
1
Y
–V
2
S
V
O
1
Z
2
S
–15V
V
= (AB/20) cos
O
0.1µF
R
X
is often used in
VO = 10 • E
OPA606
A
1
39kΩ
1kΩ
C
θ
• ES
MPY634
SBFS017A
Minor gain adjustments are accomplished with the 1kΩ variable resistor
connected to the scale factor adjustment pin, SF. Bandwidth of this circuit
is limited by A
, which is operated at relatively high gain.
1
FIGURE 7. Voltage-Controlled Amplifier.
www.ti.com
7
18kΩ
y
10kΩ
Input, E
0 to +10V
θ
X
+V
1
X
Out
2
MPY634
SFZ
Y
1
Y
–V
2
S
1
Z
2
S
4.7kΩ
4.3kΩ
–15V
+15V
V
OUT
Where
θ
= (π/2) (E /10V)
3kΩ
= (10V) sin
With a linearly changing 0-10V input, this circuit’s output follows
0° to 90° of a sine function with a 10V peak output amplitude.
Modulation
Input, ±E
M
θ
θ
Carrier Input
E
sin ωt
C
+V
X
1
X
Out
2
MPY634
SFZ
Y
1
Y
–V
2
S
1
Z
2
S
–15V
+15V
V
OUT
1 ± (E
=
/10V) EC sin ωt
M
By injecting the input carrier signal into the output through connection
to the Z
input, conventional amplitude modulation is achieved.
2
Amplification can be achieved by use of the SF pin, or Z attenuator
(at the expense of bandwidth).
FIGURE 9. Linear AM Modulator.FIGURE 8. Sine-Function Generator.
A sin ω t
Squaring a sinusoidal input creates an output frequency of
twice that of the input. The DC output component is
removed b
AC-coupling the output.
FIGURE 10. Frequency Doubler.
Modulation
Input, ±E
M
470kΩ
Carrier
Null
+15V–15V
Carrier Input
E
C
1kΩ
sin ω t
X
1
X
2
MPY634
SFZ
Y
1
Y
2
+V
X
1
X
2
MPY634
SFZ
Y
1
Y2–V
Out
+V
S
+15V
(A2/20) cos (2 ω t)
Out
C
R
–V
1
Z
2
S
–15V
Frequency Doubler
Input Signal: 20Vp-p, 200kHz
Output Signal: 10Vp-p, 400kHz
+15V
S
V
OUT
1
Z
2
S
–15V
The basic muliplier connection performs balanced modulation.
Carrier rejection can be improved by trimming the offset voltage
of the modulation input. Better carrier rejection above 2MHz is
typically achieved by interchanging the X and Y inputs (carrier
applied to the X input).
FIGURE 11. Balanced Modulator.
8
www.ti.com
Carrier: fC = 2MHz, Amplitude = 1Vrms
Signal: f
= 120kHz, Amplitude = 10V peak
S
MPY634
SBFS017A
PACKAGE OPTION ADDENDUM
www.ti.com
22-Oct-2007
PACKAGING INFORMATION
Orderable DeviceStatus
(1)
Package
Type
Package
Drawing
Pins Package
Qty
Eco Plan
MPY634AMOBSOLETETO-100LME10TBDCall TICall TI
MPY634BMOBSOLETETO-100LME10TBDCall TICall TI
MPY634KPACTIVEPDIPN1425Green (RoHS &
no Sb/Br)
MPY634KPG4ACTIVEPDIPN1425Green (RoHS &
no Sb/Br)
MPY634KUACTIVESOICDW1648Green (RoHS &
no Sb/Br)
MPY634KU/1KACTIVESOICDW161000 Green (RoHS &
no Sb/Br)
MPY634KU/1KE4ACTIVESOICDW161000 Green (RoHS &
no Sb/Br)
MPY634KUE4ACTIVESOICDW1648Green (RoHS &
no Sb/Br)
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Lead/Ball Finish MSL Peak Temp
CU NIPDAUN / A for Pkg Type
CU NIPDAUN / A for Pkg Type
CU NIPDAULevel-3-260C-168 HR
CU NIPDAULevel-3-260C-168 HR
CU NIPDAULevel-3-260C-168 HR
CU NIPDAULevel-3-260C-168 HR
(3)
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
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