MIC5018
IttyBitty
™
High-Side MOSFET Driver
General Description
The MIC5018 IttyBitty™ high-side MOSFET driver is
designed to switch an N-channel enhancement-type
MOSFET from a TTL compatible control signal in high- or
low-side switch applications. This driver features the tiny
4-lead SOT-143 package.
The MIC5018 is powered from a +2.7V to +9V supply
and features extremely low off-state supply current.
An internal charge pump drives the gate output higher
than the driver supply voltage and can sustain the gate
voltage indefinitely. An internal zener diode limits the
gate-to-source voltage to a safe level for standard
N-channel MOSFETs.
In high-side configurations, the source voltage of the
MOSFET approaches the supply voltage when switched
on. To keep the MOSFET turned on, the MIC5018’s output
drives the MOSFET gate voltage higher than the supply
voltage. In a typical high-side configuration, the driver is
powered from the load supply voltage. Under some
conditions, the MIC5018 and MOSFET can switch a load
voltage that is slightly higher than the driver supply
voltage.
In a low-side configuration, the driver can control a
MOSFET that switches any voltage up to the rating of the
MOSFET. The gate output voltage is higher than the
typical 3.3V or 5V logic supply and can fully enhance a
standard MOSFET.
The MIC5018 is available in the SOT-143 package and is
rated for –40°C to +85°C ambient temperature range.
Features
•
•
•
•
•
•
•
•
+2.7V to +9V operation
150µA typical supply current at 5V supply
≤1µA
typical standby (off) current
Charge pump for high-side low-voltage applications
Internal zener diode gate-to-ground MOSFET protection
Operates in low- and high-side configurations
TTL compatible input
ESD protected
Applications
•
•
•
•
Battery conservation
Power bus switching
Solenoid and motion control
Lamp control
Typical Applications
+5V
‡
‡
V
L O AD SU PPL Y
Load voltage limited only by
MOSFET drain-to-source rating
2
4
VS
G
3
1
Load
On
Off
C T L GND
+2.7 to +9V
4.7µF
MIC5018
2
4
On
Off
Load
3
1
4.7µF
MIC5018
IRFZ24*
N-Channel
MO S F E T
* Siliconix
30m , 7A max., 30V V
DS
max.
8-lead SOIC package
* International Rectifier
100m , 17A max.
TO-220 package
VS
G
C T L GND
Si9410DY*
N-channel
MO S F E T
Low-Voltage High-Side Power Switch
IttyBitty is a trademark of Micrel, Inc.
Low-Side Power Switch
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (
408
) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
April 2006
M9999-042406
(408) 955-1690
Micrel, Inc.
MIC5018
Ordering Information
Part Number
Standard
MIC5018BM4
Pb-Free
MIC5018YM4
H10
Making
Standard
Pb-Free
H10
–40
º
C to +85
ºC
SOT-143
Temp. Range
Package
Pin Configuration
VS
2
GND
1
Part
Identificatio
n
Early production identification:
MH10
3
H10
H10
4
G
CTL
SOT-143 (M4)
Pin Description
Pin Number
1
2
3
4
Pin Name
GND
VS
G
CTL
Pin Function
Ground: Power return.
Supply (Input): +2.7V to +9V supply.
Gate (Output): Gate connection to external MOSFET.
Control (Input): TTL compatible on/off control input. Logic high drives the gate output above the supply
voltage. Logic low forces the gate output near ground.
April 2006
2
M9999-042406
(408) 955-1690
Micrel, Inc.
MIC5018
Absolute Maximum Ratings
Supply Input Voltage (V
SUPPLY
) .....................................+10V
Control Voltage (V
CTL
) ................................... –0.6V to +16V
Gate Voltage (V
G
).........................................................+16V
Ambient Temperature Range (T
A
)...............–40°C to +85°C
Operating Ratings
Lead Temperature, soldering 10 sec ..........................300ºC
Package Thermal Resistance
SOT-143 (θ
JA
) ....................................................220°C/W
SOT-143 (θ
JC
) ....................................................130°C/W
Electrical Characteristics
Parameter
Supply Current
Conditions
(1)
V
SUPPLY
= 3.3V
V
SUPPLY
= 5V
V
CTL
= 0V
V
CTL
= 3.3V
V
CTL
= 0V
V
CTL
= 5V
V
CTL
for logic 0 input
V
CTL
for logic 1 input
V
CTL
for logic 1 input
Min
Typ
0.01
70
0
150
Max
1
140
1
300
0.8
V
SUPPLY
V
SUPPLY
Units
µA
µA
µA
µA
V
V
V
µA
pF
V
V
V
V
µA
Control Input Voltage
2.7V
≤
V
SUPPLY
≤
9V
2.7V
≤
V
SUPPLY
≤
5V
5V
≤
V
SUPPLY
≤
9V
0
2.0
2.4
0.01
5
13
6.3
7.1
11.4
16
7.1
8.2
13.4
9.5
0.75
2.1
10
30
Control Input Current
Control Input Capacitance
Zener Diode Output Clamp
Gate Output Voltage
2.7V
≤
V
SUPPLY
≤
9V
(2)
1
19
V
SUPPLY
= 9V
V
SUPPLY
= 2.7V
V
SUPPLY
= 3.0V
V
SUPPLY
= 4.5V
Gate Output Current
Gate Turn-On Time
Gate Turn-Off Time
Notes:
V
SUPPLY
= 5V
V
SUPPLY
= 4.5V
V
SUPPLY
= 4.5V
V
OUT
= 10V
(3)
(4)
C
L
= 1000pF
(4)
C
L
= 3000pF
C
L
= 1000pF
(5)
C
L
= 3000pF
1.5
4.2
20
60
Ms
ms
µs
µs
(5)
General Note: Devices are ESD protected, however handling precautions are recommended.
1. Typical values at T
A
= 25°C. Minimum and maximum values indicate performance at –40°C
≥
T
A
≥
+85°C. Parts production tested at 25°C.
2. Guaranteed by design.
3. Resistive load selected for V
OUT
= 10V.
4. Turn-on time is the time required for gate voltage to rise to 4V greater than the supply voltage. This represents a typical MOSFET gate threshold
voltage.
5. Turn-off time is the time required for the gate voltage to fall to 4V above the supply voltage. This represents a typical MOSFET gate threshold
voltage.
Test Circuit
V
S U P P L Y
0.1µF
2
4
5V
0V
MIC5018
VS
G
3
1
V
OU T
C
L
C T L GND
April 2006
3
M9999-042406
(408) 955-1690
Micrel, Inc.
MIC5018
Typical Characteristics
(4)
Supply Current
vs. Supply Voltage
1.0
0.8
-40°C
0.6
25°C
0.4
0.2
0
125°C
0
2
4
6
8
10
SUPPLY VOLTAGE (V)
20
15
Gate Output Voltage
vs. Supply Voltage
125°C
-40°C
10
5
0
25°C
0
2
4
6
8
10
SUPPLY VOLTAGE (V)
Note 4:
Note 5:
Note 6:
T
A
= 25°C, V
SUPPLY
= 5V unless noted.
Full turn-on time is the time between V
CTL
rising to 2.5V and the V
G
rising to 90% of its steady on-state value.
Full turn-off time is the time between V
CTL
falling to 0.5V and the V
G
falling to 10% of its steady on-state value.
April 2006
4
M9999-042406
(408) 955-1690
Micrel, Inc.
MIC5018
Functional Diagram
+2.7V to +9V
VS
I1
20µA
MIC5018
D2
35V
Q1
On
Off
CTL
R1 2k
D1
16V
Q2
R2
15k
EN CHARGE
PUMP
G
D3 16V
Q3
Functional Diagram with External Components
(High-Side Driver Configuration)
Functional Description
Refer to the functional diagram.
The MIC5018 is a noninverting device. Applying a logic
high signal to CTL (control input) produces gate drive
output. The G (gate) output is used to turn on an
external N-channel MOSFET.
Supply
VS (supply) is rated for +2.7V to +9V. An external
capacitor is recommended to decouple noise.
Control
CTL (control) is a TTL compatible input. CTL must be
forced high or low by an external signal. A floating input
may cause unpredictable operation.
A high input turns on Q2, which sinks the output of
current source I1, making the input of the first inverter
low. The inverter output becomes high enabling the
charge pump.
Charge Pump
The charge pump is enabled when CTL is logic high.
The charge pump consists of an oscillator and voltage
quadrupler (4×). Output voltage is limited to 16V by a
zener diode. The charge pump output voltage will be
approximately:
V
G
= 4 × V
SUPPLY
– 2.8V, but not exceeding 16V
The oscillator operates from approximately 70kHz to
approximately 100kHz depending upon the supply
voltage and temperature.
Gate Output
The charge pump output is connected directly to the G
(gate) output. The charge pump is active only when CTL
is high. When CTL is low, Q3 is turned on by the second
inverter and discharges the gate of the external
MOSFET to force it off.
If CTL is high, and the voltage applied to VS drops to
zero, the gate output will be floating (unpredictable).
ESD Protection
D1 and D2 clamp positive and negative ESD voltages.
R1 isolates the gate of Q2 from sudden changes on the
CTL input. Q1 turns on if the emitter (CTL input) is
forced below ground to provide additional input
protection. Zener D3 also clamps ESD voltages for the
gate (G) output.
April 2006
5
Load
M9999-042406
(408) 955-1690
GND
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