MAX15040EWE+T Maxim Integrated Products, MAX15040EWE+T Datasheet - Page 9

• Manufacturer Part Number: MAX15040EWE+T
• Description: DC/DC Switching Controllers 4A Step-Down w/Internal Switch
• Manufacturer: Maxim Integrated Products

Specifications of MAX15040EWE+T

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Figure 1. All-Ceramic Capacitor Design with V
The MAX15040 high-efficiency, voltage-mode switching
regulator is capable of delivering up to 4A of output
current. The MAX15040 provides output voltages from
0.6V to (0.9 x V
making it ideal for on-board point-of-load applications.
The output-voltage accuracy is better than ±1% over
load, line, and temperature.
The MAX15040 features a 1MHz fixed switching frequen-
cy, allowing the user to achieve all-ceramic capacitor
designs and fast transient responses. The high operating
frequency minimizes the size of external components.
The MAX15040 is available in a 2mm x 2mm, 16-bump
(4 x 4 array), 0.5mm pitch WLP package. The REFIN/SS
function makes the MAX15040 an ideal solution for DDR
and tracking power supplies. Using internal low-R
(15mΩ) n-channel MOSFETs for both high- and low-side
switches maintains high efficiency at both heavy-load
and high-switching frequencies.
The MAX15040 employs voltage-mode control architec-
ture with a high-bandwidth (> 15MHz) error amplifier.
The op-amp voltage-error amplifier works with Type III
compensation to fully utilize the bandwidth of the high-
frequency switching to obtain fast transient response.
High-Efficiency, 4A, Step-Down Regulator with
2.4V TO 3.6V
10Ω
1µF
C5
R1
INPUT
Integrated Switches in 2mm x 2mm Package
22µF
C1
IN
_______________________________________________________________________________________
) from 2.4V to 3.6V input supplies,
0.1µF
C3
Detailed Description
OFF
C8
0.033µF
ON
IN
IN
V
EN
REFIN/SS
DD
OUT
MAX15040
= 1.8V
GND
U1
PWRGD
DSON
COMP
GND
BST
BST
LX
LX
LX
FB
Adjustable soft-start time provides flexibilities to mini-
mize input startup inrush current. An open-drain,
power-good (PWRGD) output goes high impedance
when V
is above 0.54V. PWRGD goes low when V
90% of V
The controller logic block is the central processor that
determines the duty cycle of the high-side MOSFET
under different line, load, and temperature conditions.
Under normal operation, where the current-limit and tem-
perature protection are not triggered, the controller logic
block takes the output from the PWM comparator and
generates the driver signals for both high-side and low-
side MOSFETs. The control logic block controls the
break-before-make logic and the timing for charging the
bootstrap capacitors. The error signal from the voltage-
error amplifier is compared with the ramp signal generat-
ed by the oscillator at the PWM comparator to produce
the required PWM signal. The high-side switch turns on
at the beginning of the oscillator cycle and turns off when
the ramp voltage exceeds the V
rent-limit threshold is exceeded. The low-side switch
then turns on for the remainder of the oscillator cycle.
C9
0.1µF
820pF
C11
0.47µH
L1
33pF
C12
5.1kΩ
R4
FB
REFIN/SS
20kΩ
2.2Ω
R5
exceeds 92.5% of V
R10
470pF
430Ω
Typical Application Circuit
C10
R6
V
DD
or V
C15
1000pF
REFIN/SS
OPTIONAL
C2
22µF
Controller Function
is below 0.54V.
REFIN/SS
COMP
OUTPUT
1.8V/4A
C4
0.01µF
signal or the cur-
and V
FB
falls below
REFIN/SS
R3
8.06kΩ
1%
R7
4.02kΩ
1%
9