MAX15035 Datasheet, PDF (1/27 Pages) Maxim Integrated Products – 15A Step-Down Regulator with Internal Switches

19-4123; Rev 2; 10/08
15A Step-Down Regulator with Internal Switches
General Description
The MAX15035 pulse-width modulation (PWM) controller
provides high efficiency, excellent transient response,
and high DC-output accuracy. Combined with the inter-
nal low on-resistance MOSFETs, the MAX15035 pro-
vides a highly efficient and compact solution for small
form factor applications that need a high-power density.
Maxim’s proprietary Quick-PWM™ quick-response,
constant on-time PWM control scheme handles wide
input/output voltage ratios (low-duty-cycle applications)
with ease and provides 100ns instant-on response to
load transients while maintaining a relatively constant
switching frequency. The output voltage can be dynam-
ically controlled using the dynamic REFIN, which sup-
ports input voltages between 0V to 2V. The REFIN
adjustability combined with a resistive voltage-divider
on the feedback input allows the MAX15035 to be con-
figured for any output voltage between 0V to 0.9V_IN.
The controller senses the current across the synchro-
nous rectifier to achieve a low-cost and highly efficient
valley current-limit protection. External current-limit con-
trol is provided to allow higher current-limit settings for
applications with heatsinks and air flow, or for lower
current applications that need lower current-limit set-
tings to avoid overdesigning the application circuit. The
adjustable current limit provides a high degree of flexi-
bility, allowing thermally compensated protection or
foldback current-limit protection using a voltage-divider
partially derived from the output.
The MAX15035 includes a voltage-controlled soft-start
and soft-shutdown to limit the input surge current, pro-
vide a monotonic power-up into a precharged output,
and provide a predictable soft-start time. The controller
also includes output fault protection—undervoltage and
overvoltage protection—as well as thermal-fault protec-
tion.
The MAX15035 is available in a small 40-pin, 6mm x 6mm,
TQFN package.
Applications
Server Computers
GPU Core Supplies
DDR Memory—VDDQ or VTT
Point-of-Load Applications
Step-Down Power Supplies
Storage Power Supplies
Features
o 4.5V to 26V Input Voltage Range
o Fast Transient Response
o Monotonic Power-Up with Precharged Output
o Supports Any Output Capacitor
No Compensation Required with Polymers/
Tantalum
Stable with Ceramic Output Capacitors Using
External Compensation
o Dynamically Adjustable Output Voltage
0.5% V_OUT Accuracy Over Line and Load
o Adjustable Valley Current-Limit Protection
Thermal Compensation with NTC
Supports Foldback Current Limit
o Programmable Switching Frequency
o Overvoltage Protection
o Undervoltage Protection
o Voltage Soft-Start and Soft-Shutdown
o Power-Good Window Comparator
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX15035ETL+
-40°C to +85°C
40 TQFN-EP*
+Denotes a lead-free/RoHS-compliant package.
*EP = Exposed pad.
Pin Configuration
TOP VIEW
30 29 28 27 26 25 24 23 22 21
N.C. 31
EP1 EP3
FB 32
IN
20 IN
19 IN
ILIM 33
REFIN 34
AGND
MAX15035
18 IN
17 N.C.
REF 35
EP2
SKIP 36
16 LX
15 PGND
V_CC 37
PGOOD 38
14 PGND
LX
13 PGND
N.C. 39
12 PGND
N.C. 40
11 PGND
+ _{1 2 3 4 5 6 7 8 9 10}
Quick-PWM is a trademark of Maxim Integrated Products, Inc.
THIN QFN
(6mm x 6mm)
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.