OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

MAX8577EUB+T

P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18
General Description
The MAX8576–MAX8579 synchronous PWM buck con-
trollers use a hysteretic voltage-mode control algorithm
to achieve a fast transient response without requiring
loop compensation. The MAX8576/MAX8577 contain an
internal LDO regulator allowing the controllers to func-
tion from only one 3V to 28V input supply. The
MAX8578/MAX8579 do not contain the internal LDO
and require a separate supply to power the IC when the
input supply is higher than 5.5V. The MAX8576–
MAX8579 output voltages are adjustable from 0.6V to
0.9 x V
IN
at loads up to 15A.
Nominal switching frequency is programmable over the
200kHz to 500kHz range. High-side MOSFET sensing is
used for adjustable hiccup current-limit and short-cir-
cuit protection. The MAX8576/MAX8578 can start up
into a precharged output without pulling the output volt-
age down. The MAX8577/MAX8579 have startup output
overvoltage protection (OVP), and will pull down a
precharged output.
Applications
Motherboard Power Supplies
AGP and PCI-Express Power Supplies
Graphic-Card Power Supplies
Set-Top Boxes
Point-of-Load Power Supplies
Features
♦ 3V to 28V Supply Voltage Range
♦ 1.2% Accurate Over Temperature
♦ Adjustable Output Voltage Down to 0.6V
♦ 200kHz to 500kHz Switching Frequency
♦ Adjustable Temperature-Compensated Hiccup
Current Limit
♦ Lossless Peak Current Sensing
♦ Monotonic Startup into Prebias Output
(MAX8576/MAX8578)
♦ Startup Overvoltage Protection
(MAX8577/MAX8579)
♦ Enable/Shutdown
♦ Adjustable Soft-Start
MAX8576–MAX8579
3V to 28V Input, Low-Cost, Hysteretic
Synchronous Step-Down Controllers
________________________________________________________________ Maxim Integrated Products 1
OCSET
IN
DH
LXGND
VL
SS
FB
MAX8576
MAX8577
BST
DL
INPUT
UP TO 28V
OUTPUT
0.6V TO 0.9 x V
IN
Typical Operating Circuit
19-3289; Rev 1; 6/05
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.
EVALUATION KIT
AVAILABLE
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX8576EUB
-40°C to +85°C
10 µMAX
®
MAX8577EUB
-40°C to +85°C
10 µMAX
MAX8578EUB
-40°C to +85°C
10 µMAX
MAX8579EUB
-40°C to +85°C
10 µMAX
Pin Configurations appear at end of data sheet.
µMAX is a registered trademark of Maxim Integrated Products, Inc.
MAX8576–MAX8579
3V to 28V Input, Low-Cost, Hysteretic
Synchronous Step-Down Controllers
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
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.
IN to GND (MAX8576/MAX8577) ...........................-0.3V to +30V
VL to GND (MAX8576/MAX8577).............................-0.3V to +6V
IN to VL (MAX8576/MAX8577) ...............................-0.3V to +30V
V
CC
to GND (MAX8578/MAX8579) ..........................-0.3V to +6V
SS to GND (MAX8576/MAX8577) ...............-0.3V to (V
VL
+ 0.3)V
SS to GND (MAX8578/MAX8579)...............-0.3V to (V
CC
+ 0.3)V
DL to GND (MAX8576/MAX8577) ...............-0.3V to (V
VL
+ 0.3)V
DL to GND (MAX8578/MAX8579) ..............-0.3V to (V
CC
+ 0.3)V
BST to GND ............................................................-0.3V to +36V
BST to LX..................................................................-0.3V to +6V
LX to GND .....................-1V (-2.5V for <50ns Transient) to +30V
DH to LX..................................................-0.3V to +(V
BST
+ 0.3)V
FB to GND ................................................................-0.3V to +6V
EN to GND (MAX8578/MAX8679EUB) .....................-0.3V to +6V
OCSET to GND (MAX8576/MAX8677) ........-0.3V to (V
IN
+ 0.3)V
OCSET to GND (MAX8578/MAX8679) ...................-0.3V to +30V
OCSET to LX (MAX8576/MAX8677) ............-0.6V to (V
IN
+ 0.3)V
OCSET to LX (MAX8578/MAX8679) .......................-0.6V to +30V
DH and DL Continuous Current ............................±250mA RMS
Continuous Power Dissipation (T
A
= +70°C)
10-Pin µMAX (derate 5.6mW/°C above +70°C) ...........444mW
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
ELECTRICAL CHARACTERISTICS
(V
IN
= 12V (MAX8576/MAX8577 only), 4.7µF capacitor from VL (MAX8576/MAX8577 only) or V
CC
(MAX8578/MAX8579 only) to GND;
V
CC
= V
EN
= 5V (MAX8578/MAX8579 only); 0.01µF capacitor from SS to GND; V
FB
= 0.65V; V
BST
= 5V; V
LX
= V
GND
= 0V; V
OCSET
=
11.5V; DH = unconnected; DL = unconnected; T
A
= 0°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER CONDITIONS
MIN TYP MAX
UNITS
SUPPLY VOLTAGES
MAX8576/MAX8577 5.5
28.0
IN Supply Voltage
IN = VL (MAX8576/MAX8577) 3.0 5.5
V
V
CC
Input Voltage MAX8576/MAX8577 3.0 5.5 V
VL Output Voltage I
VL
= 10mA (MAX8576/MAX8577)
4.75
5.0
5.25
V
VL Maximum Output Current MAX8576/MAX8577 20 mA
Rising
2.75
2.8
2.90
Falling 2.4
2.45
2.5
V
VL or V
CC
Undervoltage Lockout
(UVLO)
Hysteresis
350
mV
V
IN
= 12V 0.6 2
V
IN
= V
VL
= 5V 1.1 3
No switching, V
FB
= 0.65V
(MAX8576/MAX8577)
V
IN
= V
VL
= 3.3V 0.6 2
V
CC
= 5V 0.6 2
Supply Current
V
EN
= 0V or V
FB
= 0.65V, no
switching (MAX8578/MAX8579)
V
CC
= 3.3V 0.6 2
mA
REGULATOR
Output Regulation Accuracy V
FB
peak
0.593
0.6
0.607
V
Output Regulation Hysteresis (Note 1)
12.5
20
28.0
mV
FB falling to DL falling 50
FB Propagation Delay
FB rising to DH falling 70
ns
Overvoltage-Protection (OVP)
Threshold
0.70 0.75 0.80
V
T
A
= +85°C60
High-Side Current-Sense
Program Current (Note 2)
T
A
= +25°C
42.5
50
57.5
µA
MAX8576–MAX8579
3V to 28V Input, Low-Cost, Hysteretic
Synchronous Step-Down Controllers
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= 12V (MAX8576/MAX8577 only), 4.7µF capacitor from VL (MAX8576/MAX8577 only) or V
CC
(MAX8578/MAX8579 only) to GND;
V
CC
= V
EN
= 5V (MAX8578/MAX8579 only); 0.01µF capacitor from SS to GND; V
FB
= 0.65V; V
BST
= 5V; V
LX
= V
GND
= 0V; V
OCSET
=
11.5V; DH = unconnected; DL = unconnected; T
A
= 0°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER CONDITIONS
MIN TYP MAX
UNITS
High-Side Current-Sense
Overcurrent Trip Adjustment
Range
V
IN
- V
OCSET
0.05 0.40
V
Soft-Start Internal Resistance 45 80 125 kΩ
Fault Hiccup Internal SS Pulldown
Current
V
LX
< V
OCSET
and V
FB
< V
SS
250
nA
DRIVER SPECIFICATIONS
Sourcing current 2.6 4.0
DH Driver Resistance
Sinking current 1.9 3.0
Ω
Sourcing current 2.6 4.0
DL Driver Resistance
Sinking current 1.1 2.0
Ω
Dead Time
DH low to DL high and DL low to DH high
(adaptive)
40 ns
DH Minimum On-Time
140
245 ns
Normal operation
120
220
DL Minimum On-Time
Current fault
580
ns
BST Current V
BST
- V
LX
= 5.5V, V
LX
= 28V, V
FB
< V
SS
1.65
mA
EN
Input Voltage Low V
CC
= 3V (MAX8578/MAX8579) 0.7 V
Input Voltage High V
CC
= 5.5V (MAX8578/MAX8579) 1.5 V
THERMAL SHUTDOWN
Thermal Shutdown Rising temperature, hysteresis = 20°C (typ)
+160
°C
ELECTRICAL CHARACTERISTICS
(V
IN
= 12V (MAX8576/MAX8577 only), 4.7µF capacitor from VL (MAX8576/MAX8577 only) or V
CC
(MAX8578/MAX8579 only) to GND;
V
CC
= V
EN
= 5V (MAX8578/MAX8579 only); 0.01µF capacitor from SS to GND; V
FB
= 0.65V; V
BST
= 5V; V
LX
= V
GND
= 0V; V
OCSET
=
11.5V; DH = unconnected; DL = unconnected; T
A
= -40°C to +85°C, unless otherwise noted. Note 3)
PARAMETER CONDITIONS
MIN TYP MAX
UNITS
SUPPLY VOLTAGES
MAX8576/MAX8577 5.5
28.0
IN Supply Voltage
IN = VL, MAX8576/MAX8577 3.0 5.5
V
V
CC
Input Voltage MAX8576/MAX8577 3.0 5.5 V
VL Output Voltage I
VL
= 10mA, MAX8576/MAX8577
4.75 5.25
V
VL Maximum Output Current MAX8576/MAX8577 20 mA
P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18

MAX8577EUB+T

Mfr. #:
Buy MAX8577EUB+T
Manufacturer:
Maxim Integrated
Description:
Switching Controllers 3-28V Hystrtic Synch Step-Down Controller
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet