April 2008 1 M9999-042108
MIC4426/4427/4428 Micrel, Inc.
MIC4426/4427/4428
Dual 1.5A-Peak Low-Side MOSFET Driver
General Description
The MIC4426/4427/4428 family are highly-reliable dual low-
side MOSFET drivers fabricated on a BiCMOS/DMOS process
for low power consumption and high efficiency. These drivers
translate TTL or CMOS input logic levels to output voltage
levels that swing within 25mV of the positive supply or ground.
Comparable bipolar devices are capable of swinging only
to within 1V of the supply. The MIC4426/7/8 is available in
three configurations: dual inverting, dual noninverting, and
one inverting plus one noninverting output.
The MIC4426/4427/4428 are pin-compatible replacements
for the MIC426/427/428 and MIC1426/1427/1428 with im-
proved electrical performance and rugged design (Refer to
the Device Replacement lists on the following page). They
can withstand up to 500mA of reverse current (either polarity)
without latching and up to 5V noise spikes (either polarity)
on ground pins.
Primarily intended for driving power MOSFETs, MIC4426/7/8
drivers are suitable for driving other loads (capacitive, resistive,
or inductive) which require low-impedance, high peak current,
and fast switching time. Other applications include driving
heavily loaded clock lines, coaxial cables, or piezoelectric
transducers. The only load limitation is that total driver power
dissipation must not exceed the limits of the package.
Note See MIC4126/4127/4128 for high power and narrow
pulse applications.
Functional Diagram
INA
OUTA
INVERTING
NONINVERTING
0.1mA
0.6mA
2k
INB
OUTB
INVERTING
NONINVERTING
0.1mA
0.6mA
2k
V
S
GND
Features
Bipolar/CMOS/DMOS construction
Latch-up protection to >500mA reverse current
1.5A-peak output current
4.5V to 18V operating range
Low quiescent supply current
4mA at logic 1 input
400µA at logic 0 input
Switches 1000pF in 25ns
Matched rise and rall times
7Ω output impedance
<40ns typical delay
Logic-input threshold independent of supply voltage
Logic-input protection to –5V
6pF typical equivalent input capacitance
25mV max. output offset from supply or ground
Replaces MIC426/427/428 and MIC1426/1427/1428
Dual inverting, dual noninverting, and inverting/
noninverting configurations
ESD protection
Applications
MOSFET driver
Clock line driver
Coax cable driver
Piezoelectic transducer driver
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
MIC4426/4427/4428 Micrel, Inc.
M9999-042108 2 April 2008
Ordering Information
Part Number Temperature
Standard Pb-Free Range Package Configuration
MIC4426BM MIC4426YM –40ºC to +85ºC 8-Pin SOIC Dual Inverting
MIC4426CM MIC4426ZM –0ºC to +70ºC 8-Pin SOIC Dual Inverting
MIC4426BMM MIC4426YMM –40ºC to +85ºC 8-Pin MSOP Dual Inverting
MIC4426BN MIC4426YN –40ºC to +85ºC 8-Pin PDIP Dual Inverting
MIC4426CN MIC4426ZN –0ºC to +70ºC 8-Pin PDIP Dual Inverting
MIC4427BM MIC4427YM –40ºC to +85ºC 8-Pin SOIC Dual Non-Inverting
MIC4427CM MIC4427ZM –0ºC to +70ºC 8-Pin SOIC Dual Non-Inverting
MIC4427BMM MIC4427YMM –40ºC to +85ºC 8-Pin MSOP Dual Non-Inverting
MIC4427BN MIC4427YN –40ºC to +85ºC 8-Pin PDIP Dual Non-Inverting
MIC4427CN MIC4427ZN –0ºC to +70ºC 8-Pin PDIP Dual Non-Inverting
MIC4428BM MIC4428YM –40ºC TO +85ºC 8-Pin SOIC Inverting + Non-Inverting
MIC4428CM MIC4428ZM –0ºC to +70ºC 8-Pin SOIC Inverting + Non-Inverting
MIC4428BMM MIC4428YMM –40ºC to +85ºC 8-Pin MSOP Inverting + Non-Inverting
MIC4428BN MIC4428YN –40ºC to +85ºC 8-Pin PDIP Inverting + Non-Inverting
MIC4428CN MIC4428ZN –0ºC to +70ºC 8-Pin PDIP Inverting + Non-Inverting
Note
DESC standard military drawing 5962-88503 available;
MIC4426, CERDIP 8-Pin SMD#: 5962-8850307PA
Micrel Part Number: 5952-8850307PA
MIC4427, CERDIP 8-Pin SMD#: 5962-8850308PA Micrel Part Number: 5952-8850308PA
MIC4428, CERDIP 8-Pin SMD#: 5962-8850309PA
Micrel Part Number: 5952-8850309PA
MIC426/427/428 Device Replacement
Discontinued Number Replacement
MIC426CM MIC4426BM
MIC426BM MIC4426BM
MIC426CN MIC4426BN
MIC426BN MIC4426BN
MIC427CM MIC4427BM
MIC427BM MIC4427BM
MIC427CN MIC4427BN
MIC427BN MIC4427BN
MIC428CM MIC4428BM
MIC428BM MIC4428BM
MIC428CN MIC4428BN
MIC428BN MIC4428BN
MIC1426/1427/1428 Device Replacement
Discontinued Number Replacement
MIC1426CM MIC4426BM
MIC1426BM MIC4426BM
MIC1426CN MIC4426BN
MIC1426BN MIC4426BN
MIC1427CM MIC4427BM
MIC1427BM MIC4427BM
MIC1427CN MIC4427BN
MIC1427BN MIC4427BN
MIC1428CM MIC4428BM
MIC1428BM MIC4428BM
MIC1428CN MIC4428BN
MIC1428BN MIC4428BN
April 2008 3 M9999-042108
MIC4426/4427/4428 Micrel, Inc.
Pin Configuration
1
2
3
4
8
7
6
5
NC
INA
GND
INB
NC
OUTA
VS
OUTB
MIC4426
Dual
Inverting
A
B
7
5
2
4
MIC4426 MIC4427 MIC4428
A
B
7
5
2
4
A
B
7
5
2
4
1
2
3
4
8
7
6
5
NC
INA
GND
INB
NC
OUTA
VS
OUTB
MIC4427
Dual
Noninverting
1
2
3
4
8
7
6
5
NC
INA
GND
INB
NC
OUTA
VS
OUTB
MIC4428
Inverting+
Noninverting
Pin Description
Pin Number Pin Name Pin Function
1, 8 NC not internally connected
2 INA Control Input A: TTL/CMOS compatible logic input.
3 GND Ground
4 INB Control Input B: TTL/CMOS compatible logic input.
5 OUTB Output B: CMOS totem-pole output.
6 VS Supply Input: +4.5V to +18V
7 OUTA Output A: CMOS totem-pole output.
MIC4426/4427/4428 Micrel, Inc.
M9999-042108 4 April 2008
Absolute Maximum Ratings(1)
Supply Voltage (VS) .....................................................+22V
Input Voltage (VIN) .......................... VS + 0.3V to GND – 5V
Junction Temperature (TJ) ......................................... 150°C
Storage Temperature ................................ –65°C to +150°C
Lead Temperature (10 sec.) ...................................... 300°C
ESD Rating(3)
Operating Ratings(2)
Supply Voltage (VS) ...................................... +4.5V to +18V
Temperature Range (TA)
(A) ......................................................... –55°C to +125°C
(B) ........................................................... –40°C to +85°C
Package Thermal Resistance
PDIP θJA ..........................................................................130°C/W
PDIP θJC ............................................................................ 42°C/W
SOIC θJA ........................................................... 120°C/W
SOIC θJC ............................................................75°C/W
MSOP θJA ......................................................... 250°C/W
Electrical Characteristics(4)
4.5V ≤ Vs ≤ 18V; TA = 25°C, bold values indicate full specified temperature range; unless noted.
Symbol Parameter Condition Min Typ Max Units
Input
VIH Logic 1 Input Voltage 2.4 1.4 V
2.4 1.5 V
VIL Logic 0 Input Voltage 1.1 0.8 V
1.0 0.8 V
IIN Input Current 0 ≤ VIN ≤ VS –1 1 µA
Output
VOH High Output Voltage
VS–0.025
V
VOL Low Output Voltage 0.025 V
RO Output Resistance IOUT = 10mA, VS = 18V 6 10 Ω
8 12 Ω
IPK Peak Output Current 1.5 A
I Latch-Up Protection withstand reverse current >500 mA
Switching Time
tR Rise Time test Figure 1 18 30 ns
20 40 ns
tF Fall Time test Figure 1 15 20 ns
29 40 ns
tD1 Delay Tlme test Flgure 1 17 30 ns
19 40 ns
tD2 Delay Time test Figure 1 23 50 ns
27 60 ns
tPW Pulse Width test Figure 1 400 ns
Power Supply
IS Power Supply Current VINA = VINB = 3.0V 0.6 1.4 4.5 mA
1.5 8 mA
IS Power Supply Current VINA = VINB = 0.0V 0.18 0.4 mA
0.19 0.6 mA
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. Devices are ESD sensitive. Handling precautions recommended.
4. Specification for packaged product only.
April 2008 5 M9999-042108
MIC4426/4427/4428 Micrel, Inc.
Test Circuits
A
B
INA
INB
2
4
MIC4427
5
7
OUTA
1000pF
6
VS = 18V
0.1µF 4.7µF
OUTB
1000pF
Figure 2a. Noninverting Configuration
90%
10%
tR
10%
0V
5V
tF
VS
OUTPUT
INPUT 90%
0V
tD1
tD2
tPW
2.5V
Figure 2b. Noninverting Timing
A
B
INA
INB
2
4
MIC4426
5
7
OUTA
1000pF
6
VS = 18V
0.1µF 4.7µF
OUTB
1000pF
Figure 1a. Inverting Configuration
tD1
90%
10%
tF
10%
0V
5V
tD2
tR
VS
OUTPUT
INPUT 90%
0V
2.5V
tPW
Figure 1b. Inverting Timing
MIC4426/4427/4428 Micrel, Inc.
M9999-042108 6 April 2008
Electrical Characteristics
Rise and Fall Time vs.
0 5 2010 15
tF
SUPPLY VOLTAGE (V)
70
60
50
40
10
0
TIME (ns)
20
30
0 5 2010 15
SUPPLY VOLTAGE (V)
35
30
25
20
5
0
TIME (ns)
10
15
40
30
10
TIME (ns)
20
-25 0 150
25 50
TEMPERATURE (°C)
75 100 125
35
30
25
20
5
0
TIME (ns)
10
15
-25 0 15025 50
TEMPERATURE (°C)
75 100 125
tD1
80
70
60
50
20
0
SUPPLY CURRENT (mA)
30
40
10
400kHz
200
kHz
20kHz
10 10000100
CAPACITIVE LOAD (pF)
1000
1k
100
10
1
TIME (ns)
10 10000100
CAPACITIVE LOAD (pF)
1000
tR
tF
Supply Current vs. Frequency
V = 18V
S
10 V
5 V
20
0
SUPPLY CURRENT (mA)
30
10
1 100010
FREQUENCY (kHz)
100
High Output vs. Current
| V – V | (V)
S OUT
CURRENT SOURCED (mA)
Low Output vs. Current
1.20
0.96
0
0.48
0.72
0.24
0 10
CURRENT SUNK (mA)
20 30 40 50 60 70 80 90 100
10 V
15 V
OUTPUT VOL
T
AGE (V)
1.20
0.96
0
0.48
0.72
0.24
0 10 20 30 40 50 60 70 80 90 100
10 V
15 V
-50
tR
-50
-75
tR
tF
-75
tD2
tD1
tD2
C = 1000pF
T = 25°C
L
A
C = 1000pF
T = 25°C
L
A
C = 1000pF
V = 18V
L
S
C = 1000pF
V = 18V
L
S
T = 25°C
V = 18V
A
S
T = 25°C
V = 18V
A
S
T = 25°C
C = 1000pF
L
AT = 25°C
AV = 5V
CT = 25°C
AV = 5V
S
25 50 15075 100
AMBIENT TEMPERATURE (°C)
1000
750
250
0
500
0
0.5
2.5
1.0
1.5
SUPPLY CURRENT (mA)
201550
SUPPLY VOLTAGE (V)
10
2.0
125
SUPPLY CURRENT (A)
15100 5
0
50
100
150
200
300
400
20
SUPPLY VOLTAGE (V)
MAXIMUM PACKAGE
POWER DISSIP
A
TION (mW)
1250
NO LOAD
BOTH INPUTS LOGIC "1"
T = 25°C
A
NO LOAD
BOTH INPUTS LOGIC "0"
T = 25°C
A
SOIC
PDIP
Supply Voltage
Delay Time vs.
Supply Voltage
Rise and Fall Time vs.
Temperature
Rise and Fall Time vs.
Capacitive Load
Supply Current vs.
Capacitive Load
Delay Time vs.
Temperature
Quiescent Power Supply Current
vs. Supply Voltage Quiescent Power Supply Current
vs. Supply Voltage
Package Power Dissipation
April 2008 7 M9999-042108
MIC4426/4427/4428 Micrel, Inc.
Applications Information
Supply Bypassing
Large currents are required to charge and discharge large
capacitive loads quickly. For example, changing a 1000pF
load by 16V in 25ns requires 0.8A from the supply input.
To guarantee low supply impedance over a wide frequency
range, parallel capacitors are recommended for power supply
bypassing. Low-inductance ceramic MLC capacitors with short
lead lengths (< 0.5”) should be used. A 1.0µF film capacitor
in parallel with one or two 0.1µF ceramic MLC capacitors
normally provides adequate bypassing.
Grounding
When using the inverting drivers in the MIC4426 or MIC4428,
individual ground returns for the input and output circuits or
a ground plane are recommended for optimum switching
speed. The voltage drop that occurs between the driver’s
ground and the input signal ground, during normal high-cur-
rent switching, will behave as negative feedback and degrade
switching speed.
Control Input
Unused driver inputs must be connected to logic high (which
can be VS) or ground. For the lowest quiescent current
(< 500µA) , connect unused inputs to ground. A logic-high
signal will cause the driver to draw up to 9mA.
The drivers are designed with 100mV of control input hys-
teresis. This provides clean transitions and minimizes output
stage current spikes when changing states. The control input
voltage threshold is approximately 1.5V. The control input
recognizes 1.5V up to VS as a logic high and draws less than
1µA within this range.
The MIC4426/7/8 drives the TL494, SG1526/7, MIC38C42,
TSC170 and similar switch-mode power supply integrated
circuits.
Power Dissipation
Power dissipation should be calculated to make sure that the
driver is not operated beyond its thermal ratings. Quiescent
power dissipation is negligible. A practical value for total
power dissipation is the sum of the dissipation caused by the
load and the transition power dissipation (PL + PT).
Load Dissipation
Power dissipation caused by continuous load current (when
driving a resistive load) through the driver’s output resistance
is:
PL = IL2 RO
For capacitive loads, the dissipation in the driver is:
PL = f CL VS2
Transition Dissipation
In applications switching at a high frequency, transition power
dissipation can be significant. This occurs during switching
transitions when the P-channel and N-channel output FETs
are both conducting for the brief moment when one is turning
on and the other is turning off.
PT = 2 f VS Q
Charge (Q) is read from the following graph:
1×10-8
8×10-9
4×10-9
3×10-9
2×10-9
6×10-9
1×10-9
4 6 8 10 12 14 16 18
SUPPLY VOLTAGE (V)
CHARGE (Q)
Crossover Energy Loss per Transition
MIC4426/4427/4428 Micrel, Inc.
M9999-042108 8 April 2008
Package Information
45°
0°–8°
0.228 (5.79)
0.189 (4.8)
PLANE
MAX )
0.010 (0.25)
0.007 (0.18)
0.045 (1.14)
0.0040 (0.102)
0.013 (0.33)
0.150 (3.81)
TYP
PIN 1
INCHES (MM)
0.016 (0.40)
8-Pin SOIC (M)
0.004 (0.10)
0.035 (0.89)
0.021 (0.53)
0.012 (0.03) R
0.0256 (0.65) TYP
0.012 (0.30) R
5°
0° MIN
0.112 (2.84)
0.116 (2.95)
0.012 (0.03)
0.007 (0.18)
0.005 (0.13)
0.038 (0.97)
0.032 (0.81)
INCH (MM)
0.187 (4.74)
8-Pin MM8™ MSOP (MM)
8-Pin Plastic DIP (N)
April 2008 9 M9999-042108
MIC4426/4427/4428 Micrel, Inc.
MICREL INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL + 1 (408) 944-0800 FAX + 1 (408) 474-1000 WEB http://www.micrel.com
This information furnished by Micrel in this data sheet is believed to be accurate and reliable. However no responsibility is assumed by Micrel for its use.
Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can
reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into
the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser’s
use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully indemnify
Micrel for any damages resulting from such use or sale.
© 2003 Micrel, Incorporated.