MP38 • MP38A
MP38U 1
MP38, MP38A
FEATURES
• HIGH INTERNAL DISSIPATION — 125 Watts
• HIGH VOLTAGE, HIGH CURRENT — 200V, 10A
• HIGH SLEW RATE — 10V/µs
• 4 WIRE CURRENT LIMIT SENSING
• OPTIONAL BOOST VOLTAGE INPUTS
APPLICATIONS
• LINEAR AND ROTARY MOTOR DRIVES
• YOKE/MAGNETIC FIELD EXCITATION
• PROGRAMMABLE POWER SUPPLIES TO ±95V
• INDUSTRIAL AUDIO
• PACKAGE OPTION - DIP10 - DUAL-IN-LINE
14
13
12
17
16
15
23
24
4
6
30
29
25
26
1
20
19
18
C2
C1
2
GND
28
C3
GND
+Vb
Cc2
Cc1
-IN
+IN
Iq
-Vb
Q1A
D1
Q4
Q5
Q11A
Q14
Q12
Q7
Q1B
Q2
Q6
Q11B
Q15
Q13
Q10
Q3
+Vs
+Ilim
-Ilim
OUT
-Vs
+Vs
OUT
-Vs
+Vs
OUT
-Vs
Power Operational Amplifier
MP38 • MP38A
DESCRIPTION
The MP38 is a cost-effective high voltage MOSFET
power operational amplier constructed with surface
mount components on a thermally conductive but elec-
trically isolated substrate.
While the cost is low the MP38 offers many of the
same features and performance specications
found in much more expensive hybrid power ampli-
ers.
The metal substrate allows the MP38 to dissipate
power up to 125 watts and its power supply voltages
can range up to ±100 Volts (200V total). Optional
boost voltage inputs allow the small signal portion
of the amplier to operate at higher supply voltages
than the high current output stage. The amplier
is then biased to achieve close linear swings to the
supply rails at high current for extra efcient opera-
tion. External compensation tailors performance to
the user needs. A four-wire sense technique allows
current limiting without the need to consider internal
or external mili-ohm parasitic resistance in the out-
put line. An Iq pin is available which can be used to
shut off the quiescent current in the output stage.
The output stage then operates class C and low-
ers quiescent power dissipation. This is useful in ap-
plications where output crossover distortion is not
important.
EQUIVALENTSCHEMATIC
Copyright © Apex Microtechnology, Inc. 2012
(All Rights Reserved)
www.apexanalog.com SEP2012
MP38UREVJ
MP38 • MP38A
2 MP38U
ABSOLUTEMAXIMUMRATINGS
SPECIFICATIONS
Parameter Symbol Min Max Units
SUPPLY VOLTAGE, +VS to –VS200 V
BOOST VOLTAGE ±VS ±20 V
OUTPUT CURRENT, within SOA 25 A
POWER DISSIPATION, internal 125 W
INPUT VOLTAGE, differential -20 +20 V
INPUT VOLTAGE, common mode -VB+VBV
TEMPERATURE, pin solder - 10s 200 °C
TEMPERATURE, junction (Note 2) 175 °C
TEMPERATURE, storage -40 +105 °C
OPERATING TEMPERATURE RANGE, case -40 +85 °C
Parameter
TestConditions
(Note 1)
MP38 MP38A
UnitsMin Typ Max Min Typ Max
INPUT
OFFSET VOLTAGE, initial 5 10 * 3 mV
OFFSET VOLTAGE,
vs. temperature Full temp range 50 * µV/°C
OFFSET VOLTAGE,
vs. supply 15 * µV/V
OFFSET VOLTAGE,
vs. power Full temp range 30 * µV/W
BIAS CURRENT, initial 10 200 * 100 pA
BIAS CURRENT,
vs. supply .01 * pA/V
OFFSET CURRENT, initial 10 50 * 30 pA
INPUT IMPEDANCE, DC 1010 * Ω
INPUT CAPACITANCE 20 * pF
COMMON MODE
VOLTAGE RANGE Full temp range ±VB¯
+15 ±VB¯
+12 * * V
COMMON MODE
REJECTION, DC
Full temp, range,
VCM= ±20V 86 98 * * dB
INPUT NOISE 100kHz BW, RS = 1KΩ 10 * µVrms
GAIN
OPEN LOOP, @ 15Hz Full temp range,
CC = 100pF 94 113 * * dB
GAIN BANDWIDTH PRODUCT I O = 10A 2 * MHz
POWER BANDWIDTH RL = 20Ω, VO = 180VP-P
CC = 100pF 20 * kHz
PHASE MARGIN Full temp range 60 * °
MP38 • MP38A
MP38U 3
NOTES: * The specication of MP38A is identical to the specication for MP38 in applicable column to the left.
1. Unless otherwise noted: TC = 25°C, RC = 100Ω, CC = 470pF. DC input specications are ± value
given. Power supply voltage is typical rating. ±VB = ±VS.
2. Long term operation at the maximum junction temperature will result in reduced product life. Derate
internal power dissipation to achieve high MTTF. For guidance, refer to the heatsink data sheet.
3. Rating applies if the output current alternates between both output transistors at a rate faster than
60Hz.
4. The MP38 must be used with a heat sink or the quiescent power may drive the unit to junction tem-
peratures higher than 175°C.
The MP38 is constructed from MOSFET transistors. ESD handling procedures must be observed.
CAUTION
Parameter
TestConditions
(Note 1)
MP38 MP38A
UnitsMin Typ Max Min Typ Max
OUTPUT
VOLTAGE SWING I O = 10A ±VS¯
+8.8 ±VS¯
+6.6 * * V
VOLTAGE SWING ±VB = ±VS ±10V,
I O = 10A ±VS¯
+6.8 ±VS¯
+4 * * V
SETTLING TIME to .1% A V = +1,10V step,
R L = 4Ω 2.5 * µS
SLEW RATE A V = –10, CC = 100pF 10 * V/µS
CAPACITIVE LOAD Full temp range,
A V = +1 10 * nF
RESISTANCE 4 * Ω
CURRENT, CONTINUOUS 10 11 A
POWERSUPPLY
VOLTAGE Full temp range ±15 ±75 ±100 * * * V
CURRENT, quiescent, boost
supply 22 * mA
CURRENT, quiescent, total 26 * mA
THERMAL
RESISTANCE, AC,
junction to case (Note 3)
Full temp range,
F>60Hz .9 * °C/W
RESISTANCE, DC, junction to
case
Full temp range,
F<60Hz 1.2 * °C/W
RESISTANCE,
junction to air (Note 4) Full temp range 12 * °C/W
TEMPERATURE RANGE, case Meets full range
specication -40 +85 * * °C
MP38 • MP38A
4 MP38U
PULSE RESPONSE
PULSE RESPONSE
OUTPUT VOLTAGE SWING
0
1
2
3
4
5
6
7
8
9
10
OUTPUT CURRENT, I
O
(A)
OUTPUT VOLTAGE DROP FROM SUPPLY, V
S
-V
O
(V)
+VB = +VS
0 108642
+V
B
= +V
S
+10V
-V
B
= -V
S
-10V
-V
B
= -V
S
SLEW RATE vs. COMP.
0
10
20
30
40
50
60
70
COMPENSATION CAPACITOR, (pF)
SLEW RATE (V/µs)
0 100 200 300 400 500
POWER RESPONSE
1
10
100
1K
FREQUENCY (KHz)
OUTPUT VOLTAGE, VO (VP-P)
47pF
100pF
470pF
220pF
100 1K10
SMALL SIGNAL PHASE
FREQUENCY, F (Hz)
OPEN LOOP PHASE, Ø (°)
-200
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
47pF
100pF
220pF
470pF
47pF
100pF
220pF
470pF
100 100M1M10K1
SMALL SIGNAL RESPONSE
FREQUENCY, F (Hz)
OPEN LOOP GAIN, A (dB)
-20
0
20
40
60
80
100
120
140
470pF
100pF
47pF
220pF
1 100 10K 1M 100M
SOA
SUPPLY TO OUTPUT DIFFERENTIAL, VS-VO (V)
OUTPUT CURRENT, IO (A)
1
0.2
10
20
10µs
100µs1ms
10ms
25°C
85°C
5 20010010
HARMONIC DISTORTION
0.001
0.01
0.1
1
10
FREQUENCY, F(Hz)
PERCENT DISTORTION + NOISE
A
V
= 10
V
S
= ±96V
R
L
= 24Ω
0.5W
5W
100 100K10K1K
150W
50W
0 20 40 60 80
CASE TEMPERATURE, TC (°C)
40
60
80
POWER DERATING
INTERNAL POWER DISSIPATION, P(W)
100
20
0
100
120
140
TYPICALPERFORMANCEGRAPHS
MP38 • MP38A
MP38U 5
TYPICALAPPLICATION
Ref:ApplicationNote25
The high power bandwidth and high voltage output
of the MP38 allows driving ultra-sonic transducers
via a resonant circuit including the transducer and
a matching transformer. The load circuit appears
resistive to the MP38.
GENERAL
Please read Application Note 1 "General Operat-
ing Considerations" which covers stability, supplies,
heat sinking, mounting, current limit, SOA interpre-
tation, and specication interpretation. Visit www.
apexanalog.com for design tools that help auto-
mate tasks such as calculations for stability, internal
power dissipation, current limit; heat sink selection;
Apex’s complete Application Notes library; Technical
Seminar Workbook; and Evaluation Kits.
R
F
+50V
R
I
ULTRA-
SONIC
DRIVE
-50V
NC
C
C
R
CL
TUNED
TRANSFORMER
1
+V
B
+V
S
-I
LIM
+I
LIM
OUT
-IN
+IN
-V
B
-V
S
I
Q
C
C
1
C
C
2
ULTRA-SONIC AMPLIFIER
30 23
24
15-17
4
6
25
18-20
26
MP38
29
12-14
-IN
NC
OUT
15
-Vb
24
-llim
NC
20
+IN
16
GND
28 2530 21
26
NC
27 19 17
22
23
Iq
+Ilim
18
29
Cc
+Vb
NC
+Vs
NC
7
Cc1
NC
11
GND
NC
+Vs
NC
361 10
5
Cc2
412 14
9
8
NC
NC
13
2
COMPONENT SIDE VIEW
+Vs
*
**
OUT
OUT
-Vs
-Vs
-Vs
*
EXTERNALCONNECTIONS
* SEE "BYPASSING" PARAGRAPH
Phase Compensation
Gain Cc Rc
1 470pF 100Ω
≥ 3 220pF Short
≥ 10 100pF Short
30-pinDIP
PACKAGESTYLECL
MP38 • MP38A
6 MP38U
CURRENTLIMIT
The two current limit sense lines are to be connected
directly across the current limit sense resistor. For the
current limit to work correctly pin 24 must be con-
nected to the amplier output side and pin 23 con-
nected to the load side of the current limit resistor,
RCL,asshowninFigure1. This connection will bypass
any parasitic resistances, Rp, formed by sockets and sol-
der joints as well as internal amplier losses. The current
limiting resistor may not be placed anywhere in the output
circuit except where shown in Figure 1.
The value of the current limit resistor can be calculated
as follows:
.7
RCL =
ILIMIT
BOOSTOPERATION
With the VB feature the small signal stages of the amplier are operated at higher supply voltages than the ampli-
er's high current output stage. +VS (pins 12-14) and –VS (pins 18-20) are connected to the high current output
stage. An additional 10V on the VB pins is sufcient to allow the small signal stages to drive the output transistors
into saturation and improve the output voltage swing for extra efcient operation when required. When close swing
to the supply rails is not required the +VB and +VS pins must be strapped together as well as the –VB and –VS pins.
The boost voltage pins must not be at a voltage lower than the VS pins.
BYPASSING
Proper bypassing of the power supply pins is crucial for proper operation. Bypass the ±VS pins with a aluminum
electrolytic capacitor with a value of at least 10µF per amp of expected output current. In addition a .47µF to 1µF
ceramic capacitor should be placed in parallel with each aluminum electrolytic capacitor. Both of these capacitors
have to be placed as close to the power supply pins as physically possible. If not connected to the VS pins (See
BOOST OPERATION) the VB pins should also be bypassed with a .47µF to 1µF ceramic capacitor.
USINGTHEIqPINFUNCTION
Pin 25 (Iq) can be tied to pin 6 (Cc1) to eliminate the class AB biasing current from the output stage. Typically this
would remove 1-4 mA of quiescent current. The resulting decrease in quiescent power dissipation may be impor-
tant in some applications. Note that implementing this option will raise the output impedance of the amplier and
increase crossover distortion as well.
COMPENSATION
The external compensation components CC and RC are connected to pins 4 and 6. Unity gain stability can be
achieved at any compensation capacitance greater than 470 pF with at least 60 degrees of phase margin. At higher
gains more phase shift can be tolerated in most designs and the compensation capacitance can accordingly be
reduced, resulting in higher bandwidth and slew rate.
APPLICATIONREFERENCES
For additional technical information please refer to the following application notes.
AN 1 General Operating Considerations
AN 11 Thermal Techniques
AN 38 Loop Stability with Reactive Loads
R
F
R
I
30
29
23
24
R
CL
MP38
R
P
R
L
INPUT
15–17
FIGURE 1. CURRENT LIMIT
MP38 • MP38A
MP38U 7
NEEDTECHNICALHELP?CONTACTAPEXSUPPORT!
For all Apex Microtechnology product questions and inquiries, call toll free 800-546-2739 in North America.
For inquiries via email, please contact apex.support@apexanalog.com.
International customers can also request support by contacting their local Apex Microtechnology Sales Representative.
To nd the one nearest to you, go to www.apexanalog.com
IMPORTANT NOTICE
Apex Microtechnology, Inc. has made every effort to insure the accuracy of the content contained in this document. However, the information is subject to change
without notice and is provided "AS IS" without warranty of any kind (expressed or implied). Apex Microtechnology reserves the right to make changes without further
notice to any specications or products mentioned herein to improve reliability. This document is the property of Apex Microtechnology and by furnishing this informa-
tion, Apex Microtechnology grants no license, expressed or implied under any patents, mask work rights, copyrights, trademarks, trade secrets or other intellectual
property rights. Apex Microtechnology owns the copyrights associated with the information contained herein and gives consent for copies to be made of the informa-
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extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale.
APEX MICROTECHNOLOGY PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN PRODUCTS USED FOR
LIFE SUPPORT, AUTOMOTIVE SAFETY, SECURITY DEVICES, OR OTHER CRITICAL APPLICATIONS. PRODUCTS IN SUCH APPLICATIONS ARE UNDER-
STOOD TO BE FULLY AT THE CUSTOMER OR THE CUSTOMER’S RISK.
Apex Microtechnology, Apex and Apex Precision Power are trademarks of Apex Microtechnolgy, Inc. All other corporate names noted herein may be trademarks
of their respective holders.
Copyright © Apex Microtechnology, Inc. 2012
(All Rights Reserved)
www.apexanalog.com SEP2012
MP38UREVJ