19-2997; Rev 0; 10/03
10
KIT
ATION
EVALU
E
BL
AVAILA
-PIN
TD
m
m
x
3.0
General Description
The MAX8552 highly integrated monolithic MOSFET dri-
ver is capable of driving a pair of power MOSFETs in
single or multiphase synchronous buck-converter appli-
cations that provide up to 30A output current per
phase. The MAX8552 simplifies PC board layout in mul-
tiphase systems, particularly three phases and higher.
High input voltages up to 24V allow the MAX8552 to be
used in desktop, notebook, and server applications.
Each MOSFET driver is capable of driving 3000pF
capacitive loads with only 12ns propagation delay and
11ns (typ) rise and fall times, making the MAX8552
ideal for high-frequency applications.
User-programmable break-before-make circuitry pre-
vents shoot-through currents, maximizing converter effi-
ciency. An enable input allows total driver shutdown
(<1µA typ) for power-sensitive portable applications.
The PWM control input is compatible with TTL and
CMOS logic levels. The MAX8552, along with the
MAX8524 or the MAX8525 multiphase controllers, pro-
vides flexible 2-, 3-, 4-, 6-, or 8-phase CPU core-voltage
supplies.
The MAX8552 is available in space-saving 10-pin TDFN
and µMAX packages and is specified for -40°C to
+85°C operation.
o
Single-Phase Synchronous Drivers
o
Up to 24V (max) Input Voltage
m
High-Speed, Wide-Input,
Single-Phase MOSFET Driver
Features
FN
Multiphase Buck Converters
Voltage Regulator Modules (VRMs)
Processor-Core Voltage Regulators
Desktops, Notebooks, and Servers
Switching Power Supplies
3.0
V
CC
4.5V TO 6.5V
ON
OFF
PWM CONTROL
SIGNAL
m
MAX8552
o
0.1µA (typ) Quiescent Current in Shutdown Over
Temperature
o
0.5Ω/1.0Ω/0.7Ω/1.3Ω R
OUT
Drivers
o
12ns (typ) Propagation Delay
o
11ns (typ) Rise/Fall Times with 3000pF Load
o
Adaptive Dead Time and User-Programmable
Delay Mode
o
Up to 2MHz Operation with TDFN Package
o
Up to 1.2MHz Operation with µMAX Package
o
Enable Function
o
TTL- and CMOS-Compatible Logic Inputs
o
Available in a Space-Saving Thin DFN Package
Ordering Information
PART
MAX8552EUB
MAX8552ETB
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
10 µMAX
10 TDFN
3mm x 3mm
Applications
Pin Configurations appear at end of data sheet.
Typical Operating Circuit
V
IN
6V TO 24V
V
CC
BST
GND
DH
V
OUT
1.45V AT 20A
EN
MAX8552
LX
DLY
DL
PWM
PGND
________________________________________________________________
Maxim Integrated Products
1
For pricing delivery, and ordering information please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
High-Speed, Wide-Input,
Single-Phase MOSFET Driver
MAX8552
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ..............................................................-0.3V to +7V
PWM, EN, DL, DLY to GND ........................-0.3V to (V
CC
+ 0.3V)
BST to PGND..........................................................-0.3V to +35V
LX to PGND ...............................................................-1V to +28V
DH to PGND ..............................................-0.3V to (V
BST
+ 0.3V)
DH, BST to LX...........................................................-0.3V to +7V
DH and DL Continuous Current......................................±200mA
Continuous Power Dissipation (T
A
= +70°C)
10-Pin µMAX (derate 5.6mW/°C above +70°C) ........444.4mW
10-Pin TDFN (derate 24.4mW/°C above +70°C) .......1951mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
CC
= V
BST
= V
DLY
= V
EN
= 5V, V
GND
= V
PGND
= V
LX
= 0V; T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
=
+25°C.) (Note 1)
PARAMETER
UNDERVOLTAGE PROTECTION
V
CC
Supply Voltage Range
Undervoltage Lockout (UVLO)
0.25V hysteresis
V
CC
rising
V
CC
falling
PWM = GND or V
CC
,
T
A
= +25°C
PWM = GND or V
CC
,
T
A
= +85°C
V
CC
= 6.5V, PWM = GND,
R
DLY
= 47kΩ
PWM = GND
PWM = V
CC
f
PWM
= 250kHz,
50% duty cycle
PWM = GND
PWM = V
CC
PWM = GND
PWM = V
CC
250kHz
V
BST
= 4.5V
V
BST
= 5V
V
BST
= 4.5V
V
BST
= 5V
4.5
3.25
3.0
0.04
0.1
330
25
2
1.8
0.1
1.2
0.1
1.2
2
1.3
1.2
0.7
0.6
1.1
500
50
3
3
10
2
10
2
4
2.4
Ω
µA
µA
mA
mA
µA
mA
µA
mA
6.5
3.80
3.5
1
µA
V
V
CONDITIONS
MIN
TYP
MAX
UNITS
Shutdown Supply Current
V
EN
= 0V, V
CC
= 6.5V
Idle Supply Current (I
CC
)
No switching
No switching
Control Supply Current (I
GND
)
Switching
No switching, I
CC
Driver Supply Current (I
PGND
)
No switching, I
BST
Switching, I
BST
+ I
CC
DRIVER SPECIFICATIONS
(See the
Timing Diagram)
PWM = GND,
sourcing current
DH Driver Resistance
PWM = V
CC
,
sinking current
2
_______________________________________________________________________________________
High-Speed, Wide-Input,
Single-Phase MOSFET Driver
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= V
BST
= V
DLY
= V
EN
= 5V, V
GND
= V
PGND
= V
LX
= 0V; T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
=
+25°C.) (Note 1)
PARAMETER
PWM = GND,
sourcing current
DL Driver Resistance
PWM = V
CC
,
sinking current
DH Rise Time (t
rDH
)
DH Fall Time (t
fDH
)
DL Rise Time (t
rDL
)
DL Fall Time (t
fDL
)
DH Propagation Delay
PWM = V
CC
PWM = GND
PWM = V
CC
PWM = GND
PWM falling (t
pDHf
)
PWM = V
CC,
DL falling (t
pDHr
)
PWM rising (t
pDLf
)
DL Propagation Delay
EN
V
PWM
= 0V or 6.5V, V
EN
= 0V or 6.5V,
V
CC
= 6.5V, T
A
= +25°C
V
PWM
= 0V or 6.5V, V
EN
= 0V or 6.5V,
V
CC
= 6.5V, T
A
= +85°C
Input-Voltage High Threshold
Input-Voltage Low Threshold
PWM
V
PWM
= 0V or 6.5V, V
EN
= 0V or 6.5V,
V
CC
= 6.5V, T
A
= +25°C
V
PWM
= 0V or 6.5V, V
EN
= 0V or 6.5V,
V
CC
= 6.5V, T
A
= +85°C
Input-Voltage High Threshold
Input-Voltage Low Threshold
Input Threshold Hysteresis
DLY
Delay Program Accuracy
Delay Disable-Detection
Threshold
R
DLY
= 47kΩ, DL fall to DH rise
67.5
4.0
90.0
112.5
4.7
ns
V
V
CC
= 6.5V
V
CC
= 4.5V
1.2
0.5
0.01
0.1
3.5
V
V
V
1
µA
V
CC
= 6.5V
V
CC
= 4.5V
0.8
0.01
0.1
2.5
V
V
1
µA
PWM = GND,
LX falling (t
pDLr
)
V
BST
- V
LX
= 5V
CONDITIONS
V
CC
= 4.5V
V
CC
= 5V
V
CC
= 4.5V
V
CC
= 5V
V
BST
= 5V, 3000pF load
V
BST
= 5V, 3000pF load
V
CC
= 5V, 3000pF load
V
CC
= 5V, 3000pF load
V
BST
= 5V
V
BST
= 5V
MIN
TYP
1.0
0.9
0.5
0.45
14
9
11
8
12
14
9
16
ns
ns
ns
ns
ns
ns
0.8
MAX
1.6
Ω
UNITS
MAX8552
Leakage Current
Leakage Current
Note 1:
Specifications are production tested at T
A
= +25°C. Maximum and minimum limits are guaranteed by design and characterization.
_______________________________________________________________________________________
3
High-Speed, Wide-Input,
Single-Phase MOSFET Driver
MAX8552
Typical Operating Characteristics
(V
CC
= V
DLY
= 5V, C
HS_LOAD
= C
LS_LOAD
= 3000pF, 50% duty ratio.)
PACKAGE-POWER DISSIPATION
vs. PWM FREQUENCY
MAX8552 toc01
PACKAGE-POWER DISSIPATION
vs. CAPACITIVE LOAD ON DH AND DL
MAX8552 toc02
DL RISE AND FALL TIMES
vs. CAPACITIVE LOAD
18
16
RISE AND FALL TIME (ns)
14
12
10
8
6
4
2
0
1000
2000
3000
CAPACITANCE (pF)
4000
5000
FALL TIME
RISE TIME
MAX8552 toc03
500
450
400
350
P
D
(mW)
300
250
200
150
100
50
0
0
A: C
HS
= 3300pF; C
LS
= 3300pF
B: C
HS
= 3300pF; C
LS
= 5600pF
C: C
HS
= 1500pF; C
LS
= 3300pF
B
A
500
450
400
350
P
D
(mW)
300
250
200
150
100
A: f
S
= 300kHz
B: f
S
= 600kHz
C: f
S
= 1MHz
C
20
C
B
A
C
DH
= C
DL
V
CC
= 6.5V
1000 1500 2000 2500 3000 3500 4000 4500 5000
CAPACITANCE (pF)
V
CC
= 6.5V
200
400
600
800
1000
1200
50
0
PWM FREQUENCY (kHz)
DH RISE AND FALL TIMES
vs. CAPACITIVE LOAD
MAX8552 toc04
DH AND DL RISE AND FALL TIMES
vs. TEMPERATURE
MAX8552 toc05
CONTROL-CIRCUITRY CURRENT
vs. PWM FREQUENCY
MAX8552 toc06
25
RISE TIME
RISE AND FALL TIME (ns)
20
18
16
RISE AND FALL TIME (ns)
14
12
10
8
6
2
4
DL FALL
DH RISE
1.2
1.0
V
CC
= 6.5V
0.8
I
GND
(mA)
DL RISE
DH FALL
15
0.6
0.4
0.2
0
V
CC
= 5V
10
FALL TIME
5
V
EN
= 0V
0
1000 1500 2000 2500 3000 3500 4000 4500 5000
CAPACITANCE (pF)
0
-40 -20
0
20
40
60
80 100 120
TEMPERATURE (°C)
0
200
400
600
800
1000
1200
PWM FREQUENCY (kHz)
PROPAGATION DELAY
vs. TEMPERATURE
MAX8552 toc07
PROGRAMMABLE DELAY (t
DLY
)
vs. R
DLY
MAX8552 toc08
TYPICAL APPLICATION CIRCUIT
SWITCHING WAVEFORMS
MAX8552 toc09
30
DL FALL TO DH RISE
25
PROPAGATION DELAY (ns)
20
15
10
PWM RISE TO DL FALL
5
0
-40 -20
0
20
40
60
80
100 120
TEMPERATURE (°C)
PWM FALL TO DH FALL
200
180
PROGRAMMABLE DELAY (ns)
160
140
120
100
80
60
40
20
0
5
25
45
65
R
DLY
(kΩ)
85
105
V
PWM
5V/div
V
LX
10V/div
V
DL
5V/div
125
V
DH
100ns/div
20V/div
4
_______________________________________________________________________________________
High-Speed, Wide-Input,
Single-Phase MOSFET Driver
MAX8552
Pin Description
PIN
1
NAME
V
CC
FUNCTION
Input Supply Voltage. Connect to a supply voltage in the 4.5V to 6.5V range. Bypass to PGND with a
2.2µF or larger capacitor, and bypass to GND with a 0.47µF or larger capacitor.
External Synchronous-Rectifier N-MOSFET Gate-Driver Output. Swings between V
CC
and PGND.
Anticrowbar feature prevents DL from turning on until DH is off and (LX - PGND) < 2V. DL is pulled to
GND in shutdown.
Power Ground
Analog Ground
Dead-Time Delay Programming Input. Connect a resistor from DLY to GND to set the dead-time delay
between when DL falls and when DH rises. Connect DLY to V
CC
to disable the delay function. See the
Typical Operating Characteristics
for R
DLY
selection.
PWM Input. DH is high when PWM is high; DL is high when PWM is low. Input frequency can be as
high as 1.2MHz for the 10-pin µMAX package and as high as 2MHz for the 10-pin TDFN package.
Enable Input. Drive high to enable output drivers. Drive low to disable output drivers and place the IC
in low-power shutdown mode.
Switching Node and Inductor Connection. Low power supply for the DH high-side gate driver.
Connect to the source of the high-side N-MOSFET and the drain of the low-side N-MOSFET, as well
as the switched side of the inductor.
External High-Side N-MOSFET Gate-Driver Output. Swings between LX and BST. Anticrowbar feature
delays DH from turning on until DL is off. An additional user-programmable delay can be added. DH
is pulled to LX in shutdown.
Boost Flying-Capacitor Connection. Gate-drive power supply for DH high-side gate driver. Connect a
0.47µF or larger capacitor between BST and LX.
Exposed Paddle. Connect to GND.
2
3
4
5
DL
PGND
GND
DLY
6
7
PWM
EN
8
LX
9
DH
10
—
BST
Exposed
Paddle*
*10-pin
TDFN only.
_______________________________________________________________________________________
5
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