MICREL MIC4452BN

MIC4451/4452
Micrel
MIC4451/4452
12A-Peak Low-Side MOSFET Driver
Bipolar/CMOS/DMOS Process
General Description
Features
MIC4451 and MIC4452 CMOS MOSFET drivers are tough,
efficient, and easy to use. The MIC4451 is an inverting
driver, while the MIC4452 is a non-inverting driver.
• BiCMOS/DMOS Construction
• Latch-Up Proof: Fully Isolated Process is Inherently
Immune to Any Latch-up.
• Input Will Withstand Negative Swing of Up to 5V
• Matched Rise and Fall Times ............................... 25ns
• High Peak Output Current ............................ 12A Peak
• Wide Operating Range .............................. 4.5V to 18V
• High Capacitive Load Drive ........................... 62,000pF
• Low Delay Time ........................................... 30ns Typ.
• Logic High Input for Any Voltage from 2.4V to VS
• Low Supply Current .............. 450µA With Logic 1 Input
• Low Output Impedance ........................................ 1.0Ω
• Output Voltage Swing to Within 25mV of GND or VS
• Low Equivalent Input Capacitance (typ) ................. 7pF
Both versions are capable of 12A (peak) output and can
drive the largest MOSFETs with an improved safe operating
margin. The MIC4451/4452 accepts any logic input from
2.4V to VS without external speed-up capacitors or resistor
networks. Proprietary circuits allow the input to swing negative by as much as 5V without damaging the part. Additional
circuits protect against damage from electrostatic discharge.
MIC4451/4452 drivers can replace three or more discrete
components, reducing PCB area requirements, simplifying
product design, and reducing assembly cost.
Modern Bipolar/CMOS/DMOS construction guarantees freedom from latch-up. The rail-to-rail swing capability of CMOS/
DMOS insures adequate gate voltage to the MOSFET during power up/down sequencing. Since these devices are
fabricated on a self-aligned process, they have very low
crossover current, run cool, use little power, and are easy to
drive.
Applications
•
•
•
•
•
•
•
•
Switch Mode Power Supplies
Motor Controls
Pulse Transformer Driver
Class-D Switching Amplifiers
Line Drivers
Driving MOSFET or IGBT Parallel Chip Modules
Local Power ON/OFF Switch
Pulse Generators
Functional Diagram
VS
0.3mA
MIC4451
INVERTING
0.1mA
OUT
IN
2kΩ
MIC4452
NONINVERTING
GND
5-70
April 1998
MIC4451/4452
Micrel
Ordering Information
Part No.
MIC4451BN
Temperature Range
–40°C to +85°C
Package
8-Pin PDIP
Configuration
Inverting
MIC4451BM
MIC4451CT
MIC4452BN
–40°C to +85°C
0°C to +70°C
–40°C to +85°C
8-Pin SOIC
5-Pin TO-220
8-Pin PDIP
Inverting
Inverting
Non-Inverting
MIC4452BM
MIC4452CT
–40°C to +85°C
0°C to +70°C
8-Pin SOIC
5-Pin TO-220
Non-Inverting
Non-Inverting
Pin Configurations
VS 1
8 VS
IN 2
7 OUT
NC 3
6 OUT
GND 4
5 GND
5
Plastic DIP (N)
SOIC (M)
TAB
5
4
3
2
1
OUT
GND
VS
GND
IN
TO-220-5 (T)
Pin Description
Pin Number
TO-220-5
Pin Number
DIP, SOIC
Pin Name
Pin Function
1
2
IN
Control Input
2, 4
4, 5
GND
3, TAB
1, 8
VS
5
6, 7
OUT
3
NC
April 1998
Ground: Duplicate pins must be externally connected together.
Supply Input: Duplicate pins must be externally connected together.
Output: Duplicate pins must be externally connected together.
Not connected.
5-71
MIC4451/4452
Absolute Maximum Ratings
Micrel
Operating Ratings
(Notes 1, 2 and 3)
Supply Voltage .............................................................. 20V
Input Voltage .................................. VS + 0.3V to GND – 5V
Input Current (VIN > VS) ............................................ 50 mA
Power Dissipation, TAMBIENT ≤ 25°C
PDIP .................................................................... 960mW
SOIC ................................................................. 1040mW
5-Pin TO-220 .............................................................. 2W
Power Dissipation, TCASE ≤ 25°C
5-Pin TO-220 ......................................................... 12.5W
Derating Factors (to Ambient)
PDIP ................................................................ 7.7mW/°C
SOIC .............................................................. 8.3 mW/°C
5-Pin TO-220 .................................................... 17mW/°C
Storage Temperature ............................... –65°C to +150°C
Lead Temperature (10 sec) ....................................... 300°C
Operating Temperature (Chip) .................................. 150°C
Operating Temperature (Ambient)
C Version ................................................... 0°C to +70°C
B Version ................................................ –40°C to +85°C
Thermal Impedances (To Case)
5-Pin TO-220 (θJC) .............................................. 10°C/W
Electrical Characteristics:
(TA = 25°C with 4.5 V ≤ VS ≤ 18 V unless otherwise specified.)
Symbol
Parameter
Conditions
Min
Typ
2.4
1.3
Max
Units
INPUT
VIH
Logic 1 Input Voltage
VIL
Logic 0 Input Voltage
VIN
Input Voltage Range
IIN
Input Current
0 V ≤ VIN ≤ VS
VOH
High Output Voltage
See Figure 1
VOL
Low Output Voltage
See Figure 1
RO
Output Resistance,
Output High
IOUT = 10 mA, VS = 18V
RO
Output Resistance,
Output Low
IPK
Peak Output Current
IDC
Continuous Output Current
IR
Latch-Up Protection
Withstand Reverse Current
1.1
V
0.8
V
–5
VS+.3
V
–10
10
µA
OUTPUT
VS–.025
V
.025
V
0.6
1.5
Ω
IOUT = 10 mA, VS = 18V
0.8
1.5
Ω
VS = 18 V (See Figure 6)
12
Duty Cycle ≤ 2%
t ≤ 300 µs
A
2
A
>1500
mA
SWITCHING TIME (Note 3)
tR
Rise Time
Test Figure 1, CL = 15,000 pF
20
40
ns
tF
Fall Time
Test Figure 1, CL = 15,000 pF
24
50
ns
tD1
Delay Time
Test Figure 1
15
30
ns
tD2
Delay Time
Test Figure 1
35
60
ns
VIN = 3 V
VIN = 0 V
0.4
80
1.5
150
mA
µA
18
V
Power Supply
IS
Power Supply Current
VS
Operating Input Voltage
4.5
5-72
April 1998
MIC4451/4452
Micrel
Electrical Characteristics:
(Over operating temperature range with 4.5V < VS < 18V unless otherwise specified.)
Symbol
Parameter
Conditions
Min
Typ
2.4
1.4
Max
Units
INPUT
VIH
Logic 1 Input Voltage
VIL
Logic 0 Input Voltage
VIN
Input Voltage Range
IIN
Input Current
0V ≤ VIN ≤ VS
VOH
High Output Voltage
Figure 1
VOL
Low Output Voltage
Figure 1
RO
Output Resistance,
Output High
IOUT = 10mA, VS = 18V
RO
Output Resistance,
Output Low
V
1.0
0.8
V
–5
VS+.3
V
–10
10
µA
OUTPUT
VS–.025
V
0.025
V
0.8
2.2
Ω
IOUT = 10mA, VS = 18V
1.3
2.2
Ω
SWITCHING TIME (Note 3)
tR
Rise Time
Figure 1, CL = 15,000pF
23
50
ns
tF
Fall Time
Figure 1, CL = 15,000pF
30
60
ns
tD1
Delay Time
Figure 1
20
40
ns
tD2
Delay Time
Figure 1
40
80
ns
VIN = 3V
VIN = 0V
0.6
0.1
3
0.4
mA
18
V
POWER SUPPLY
IS
Power Supply Current
VS
Operating Input Voltage
NOTE 1:
NOTE 2:
NOTE 3:
4.5
Functional operation above the absolute maximum stress ratings is not implied.
Static-sensitive device. Store only in conductive containers. Handling personnel and equipment should be grounded to
prevent damage from static discharge.
Switching times guaranteed by design.
Test Circuits
VS = 18V
VS = 18V
0.1µF
0.1µF
IN
1.0µF
0.1µF
0.1µF
OUT
IN
OUT
15000pF
15000pF
MIC4451
INPUT
MIC4452
5V
90%
tPW ≥ 0.5µs
10%
0V
VS
90%
tD1
tPW
tF
tD2
INPUT
5V
90%
tPW ≥ 0.5µs
10%
0V
tR
VS
90%
tD1
tPW
tR
tD2
tF
OUTPUT
OUTPUT
10%
0V
10%
0V
Figure 2. Noninverting Driver Switching Time
Figure 1. Inverting Driver Switching Time
April 1998
1.0µF
5-73
5
MIC4451/4452
Micrel
TIME (ns)
6
8 10 12 14 16
SUPPLY VOLTAGE (V)
Fall Time
vs. Capacitive Load
150
10V
100
200
5V
150
10V
100
18V
18V
50
4
6
kH
z
1000
10k
CAPACITIVE LOAD (pF)
45
30
Hz
100k
1M
FREQUENCY (Hz)
10M
20
10k
100
1000
10k
CAPACITIVE LOAD (pF)
100k
Supply Current
vs. Frequency
100k
1M
FREQUENCY (Hz)
5-74
10M
µF
0.01
50
40
pF
30
1000
pF
µF
1000
0.01
F
40
0
1M
15
VS = 5V
SUPPLY CURRENT (mA)
20
0.1µ
pF
1000
µF
60
18
Supply Current
vs. Capacitive Load
60
100
60
16
60
0
100k
Supply Current
vs. Frequency
80
8 10 12 14
VOLTAGE (V)
F
100
50
1
30
z
MH
z
60
H
50
90
120
40
10k
75
VS = 12V
0.01
80
10-8
VS = 5V
120
0
100k
VS = 18V
120
PER TRANSITION
10-9
100k
Supply Current
vs. Capacitive Load
0k
z
kH
z
H
0k
1000
10k
CAPACITIVE LOAD (pF)
Supply Current
vs. Frequency
100
1000
10k
CAPACITIVE LOAD (pF)
20
z
H
1M
100
100
120
Crossover Energy
vs. Supply Voltage
10-7
VS = 12V
SUPPLY CURRENT (mA)
VS = 18V
140
0
150
SUPPLY CURRENT (mA)
160
0
100k
Supply Current
vs. Capacitive Load
F
SUPPLY CURRENT (mA)
180
1000
10k
CAPACITIVE LOAD (pF)
20
220
200
180
160
140
120
100
80
60
40
20
0
100
0.1µ
SUPPLY CURRENT (mA)
0
50
-40
0
40
80
TEMPERATURE (°C)
z
5V
200
0
18
250
FALL TIME (ns)
RISE TIME (ns)
250
4
10
kH
300
10,000pF
tRISE
50
Rise Time
vs. Capacitive Load
20
22,000pF
z
18
30
H
6
8 10 12 14 16
SUPPLY VOLTAGE (V)
tFALL
40
0.1µ
4
47,000pF
0k
10,000pF
CL = 10,000pF
VS = 18V
50
20
22,000pF
Rise and Fall Times
vs. Temperature
60
CROSSOVER ENERGY (A•s)
300
47,000pF
220
200
180
160
140
120
100
80
60
40
20
0
Fall Time
vs. Supply Voltage
SUPPLY CURRENT (mA)
220
200
180
160
140
120
100
80
60
40
20
0
Rise Time
vs. Supply Voltage
FALL TIME (ns)
RISE TIME (ns)
Typical Characteristic Curves
20
10
0
10k
100k
1M
FREQUENCY (Hz)
10M
April 1998
MIC4451/4452
Micrel
Typical Characteristic Curves (Cont.)
20
tD1
10
QUIESCENT SUPPLY CURRENT (µA)
0
4
6
8 10 12 14 16
SUPPLY VOLTAGE (V)
18
Quiescent Supply Current
vs. Temperature
1000
VS = 18V
INPUT = 1
100
INPUT = 0
10
April 1998
-40
0
40
80
TEMPERATURE (°C)
120
Propagation Delay
vs. Input Amplitude
50
Propagation Delay
vs. Temperature
VS = 10V
40
TIME (ns)
tD2
30
TIME (ns)
TIME (ns)
40
HIGH-STATE OUTPUT RESISTANCE (Ω)
50
120
110
100
90
80
70
60
50
40
30
20
10
0
30
tD2
20
tD2
tD1
10
0
2
4
6
INPUT (V)
tD1
8
0
10
High-State Output Resist.
vs. Supply Voltage
2.4
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
TJ = 150°C
TJ = 25°C
4
6
8 10 12 14 16
SUPPLY VOLTAGE (V)
5-75
18
LOW-STATE OUTPUT RESISTANCE (Ω)
Propagation Delay
vs. Supply Voltage
-40
0
40
80
TEMPERATURE (°C)
120
Low-State Output Resist.
vs. Supply Voltage
2.4
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
TJ = 150°C
TJ = 25°C
4
6
8 10 12 14 16
SUPPLY VOLTAGE (V)
18
5
MIC4451/4452
Micrel
Applications Information
Supply Bypassing
Charging and discharging large capacitive loads quickly
requires large currents. For example, changing a 10,000pF
load to 18V in 50ns requires 3.6A.
The MIC4451/4452 has double bonding on the supply pins,
the ground pins and output pins. This reduces parasitic lead
inductance. Low inductance enables large currents to be
switched rapidly. It also reduces internal ringing that can
cause voltage breakdown when the driver is operated at or
near the maximum rated voltage.
Internal ringing can also cause output oscillation due to
feedback. This feedback is added to the input signal since it
is referenced to the same ground.
V DD
1µF
V DD
MIC4451
φ
2
φ1 DRIVE SIGNAL
φ
DRIVE
LOGIC
CONDUCTION ANGLE
CONTROL 0° TO 180°
CONDUCTION ANGLE
CONTROL 180° TO 360°
1
M
φ
3
V DD
V DD
1µF
MIC4452
PHASE 1 OF 3 PHASE MOTOR
DRIVER USING MIC4451/4452
To guarantee low supply impedance over a wide frequency
range, a parallel capacitor combination is recommended for
supply bypassing. Low inductance ceramic disk capacitors
with short lead lengths (< 0.5 inch) should be used. A 1µF low
ESR film capacitor in parallel with two 0.1µF low ESR ceramic
capacitors, (such as AVX RAM GUARD®), provides adequate bypassing. Connect one ceramic capacitor directly
between pins 1 and 4. Connect the second ceramic capacitor
directly between pins 8 and 5.
Grounding
The high current capability of the MIC4451/4452 demands
careful PC board layout for best performance. Since the
MIC4451 is an inverting driver, any ground lead impedance
will appear as negative feedback which can degrade switching speed. Feedback is especially noticeable with slow-rise
time inputs. The MIC4451 input structure includes 200mV of
hysteresis to ensure clean transitions and freedom from
oscillation, but attention to layout is still recommended.
Figure 5 shows the feedback effect in detail. As the MIC4451
input begins to go positive, the output goes negative and
several amperes of current flow in the ground lead. As little as
0.05Ω of PC trace resistance can produce hundreds of
millivolts at the MIC4451 ground pins. If the driving logic is
referenced to power ground, the effective logic input level is
reduced and oscillation may result.
To insure optimum performance, separate ground traces
should be provided for the logic and power connections.
Connecting the logic ground directly to the MIC4451 GND
pins will ensure full logic drive to the input and ensure fast
output switching. Both of the MIC4451 GND pins should,
however, still be connected to power ground.
Figure 3. Direct Motor Drive
+15
(x2) 1N4448
5.6 kΩ
OUTPUT VOLTAGE vs LOAD CURRENT
560 Ω
30
0.1µF
50V
+
1
8
2
0.1µF
WIMA
MKS 2
1µF
50V
MKS 2
6, 7
VOLTS
29
BYV 10 (x 2)
+
4
12 Ω LINE
27
26
MIC4451
5
28
+
560µF 50V
100µF 50V
UNITED CHEMCON SXE
25
0
50
100 150 200 250 300 350
mA
Figure 4. Self Contained Voltage Doubler
5-76
April 1998
MIC4451/4452
Micrel
Input Stage
The input voltage level of the MIC4451 changes the quiescent supply current. The N channel MOSFET input stage
transistor drives a 320µA current source load. With a logic “1”
input, the maximum quiescent supply current is 400µA. Logic
“0” input level signals reduce quiescent current to 80µA
typical.
The MIC4451/4452 input is designed to provide 200mV of
hysteresis. This provides clean transitions, reduces noise
sensitivity, and minimizes output stage current spiking when
changing states. Input voltage threshold level is approximately 1.5V, making the device TTL compatible over the full
temperature and operating supply voltage ranges. Input
current is less than ±10µA.
The MIC4451 can be directly driven by the TL494, SG1526/
1527, SG1524, TSC170, MIC38C42, and similar switch
mode power supply integrated circuits. By offloading the
power-driving duties to the MIC4451/4452, the power supply
controller can operate at lower dissipation. This can improve
performance and reliability.
The input can be greater than the VS supply, however, current
will flow into the input lead. The input currents can be as high
as 30mA p-p (6.4mARMS) with the input. No damage will
occur to MIC4451/4452 however, and it will not latch.
The input appears as a 7pF capacitance and does not change
even if the input is driven from an AC source. While the device
will operate and no damage will occur up to 25V below the
negative rail, input current will increase up to 1mA/V due to
the clamping action of the input, ESD diode, and 1kΩ resistor.
dissipation limit can easily be exceeded. Therefore, some
attention should be given to power dissipation when driving
low impedance loads and/or operating at high frequency.
The supply current vs. frequency and supply current vs
capacitive load characteristic curves aid in determining power
dissipation calculations. Table 1 lists the maximum safe
operating frequency for several power supply voltages when
driving a 10,000pF load. More accurate power dissipation
figures can be obtained by summing the three dissipation
sources.
Given the power dissipation in the device, and the thermal
resistance of the package, junction operating temperature for
any ambient is easy to calculate. For example, the thermal
resistance of the 8-pin plastic DIP package, from the data
sheet, is 130°C/W. In a 25°C ambient, then, using a maximum
junction temperature of 125°C, this package will dissipate
960mW.
Accurate power dissipation numbers can be obtained by
summing the three sources of power dissipation in the device:
• Load Power Dissipation (PL)
• Quiescent power dissipation (PQ)
• Transition power dissipation (PT)
Calculation of load power dissipation differs depending on
whether the load is capacitive, resistive or inductive.
Resistive Load Power Dissipation
Dissipation caused by a resistive load can be calculated as:
PL = I2 RO D
Power Dissipation
where:
CMOS circuits usually permit the user to ignore power
dissipation. Logic families such as 4000 and 74C have
outputs which can only supply a few milliamperes of current,
and even shorting outputs to ground will not force enough
current to destroy the device. The MIC4451/4452 on the other
hand, can source or sink several amperes and drive large
capacitive loads at high frequency. The package power
I = the current drawn by the load
RO = the output resistance of the driver when the output is
high, at the power supply voltage used. (See data
sheet)
D = fraction of time the load is conducting (duty cycle)
Capacitive Load Power Dissipation
Dissipation caused by a capacitive load is simply the energy
placed in, or removed from, the load capacitance by the
+18
WIMA
MKS-2
1 µF
5.0V
1
8
6, 7
TEK CURRENT
PROBE 6302
Table 1: MIC4451 Maximum
Operating Frequency
VS
Max Frequency
18 V
MIC4451
0V
0V
5
0.1µF
0.1µF
4
LOGIC
GROUND
2,500 pF
POLYCARBONATE
12 AMPS
300 mV
PC TRACE RESISTANCE = 0.05Ω
POWER
GROUND
220kHz
300kHz
10V
5V
640kHz
2MHz
Conditions: 1. θJA = 150°C/W
2. TA = 25°C
3. CL = 10,000pF
Figure 5. Switching Time Degradation Due to
Negative Feedback
April 1998
18V
15V
5-77
5
MIC4451/4452
Micrel
driver. The energy stored in a capacitor is described by the
equation:
E = 1/2 C V2
As this energy is lost in the driver each time the load is
charged or discharged, for power dissipation calculations the
1/2 is removed. This equation also shows that it is good
practice not to place more voltage on the capacitor than is
necessary, as dissipation increases as the square of the
voltage applied to the capacitor. For a driver with a capacitive
load:
VS = power supply voltage
Transition Power Dissipation
Transition power is dissipated in the driver each time its
output changes state, because during the transition, for a
very brief interval, both the N- and P-channel MOSFETs in
the output totem-pole are ON simultaneously, and a current
is conducted through them from VS to ground. The transition
power dissipation is approximately:
PT = 2 f VS (A•s)
where (A•s) is a time-current factor derived from the typical
characteristic curve “Crossover Energy vs. Supply Voltage.”
PL = f C (VS)2
where:
Total power (PD) then, as previously described is:
f = Operating Frequency
C = Load Capacitance
VS = Driver Supply Voltage
PD = PL + PQ + PT
Definitions
Inductive Load Power Dissipation
CL = Load Capacitance in Farads.
For inductive loads the situation is more complicated. For the
part of the cycle in which the driver is actively forcing current
into the inductor, the situation is the same as it is in the
resistive case:
D = Duty Cycle expressed as the fraction of time the
input to the driver is high.
f = Operating Frequency of the driver in Hertz
IH = Power supply current drawn by a driver when both
inputs are high and neither output is loaded.
PL1 = I2 RO D
However, in this instance the RO required may be either the
on resistance of the driver when its output is in the high state,
or its on resistance when the driver is in the low state,
depending on how the inductor is connected, and this is still
only half the story. For the part of the cycle when the inductor
is forcing current through the driver, dissipation is best
described as
PL2 = I VD (1 – D)
where VD is the forward drop of the clamp diode in the driver
(generally around 0.7V). The two parts of the load dissipation
must be summed in to produce PL
PL = PL1 + PL2
Quiescent Power Dissipation
Quiescent power dissipation (PQ, as described in the input
section) depends on whether the input is high or low. A low
input will result in a maximum current drain (per driver) of
≤ 0.2mA; a logic high will result in a current drain of ≤ 3.0mA.
Quiescent power can therefore be found from:
IL = Power supply current drawn by a driver when both
inputs are low and neither output is loaded.
ID = Output current from a driver in Amps.
PD = Total power dissipated in a driver in Watts.
PL = Power dissipated in the driver due to the driver’s
load in Watts.
PQ = Power dissipated in a quiescent driver in Watts.
PT = Power dissipated in a driver when the output
changes states (“shoot-through current”) in Watts.
NOTE: The “shoot-through” current from a dual
transition (once up, once down) for both drivers is
stated in Figure 7 in ampere-nanoseconds. This
figure must be multiplied by the number of repetitions per second (frequency) to find Watts.
RO = Output resistance of a driver in Ohms.
VS = Power supply voltage to the IC in Volts.
PQ = VS [D IH + (1 – D) IL]
where:
IH = quiescent current with input high
IL = quiescent current with input low
D = fraction of time input is high (duty cycle)
5-78
April 1998
MIC4451/4452
Micrel
+18 V
WIMA
MK22
1 µF
5.0V
1
8
2
6, 7
TEK CURRENT
PROBE 6302
18 V
MIC4452
0V
0V
5
0.1µF
0.1µF
4
15,000 pF
POLYCARBONATE
Figure 6. Peak Output Current Test Circuit
5
April 1998
5-79