MAX15041ETE+T Maxim Integrated Products, MAX15041ETE+T Datasheet - Page 15

• Manufacturer Part Number: MAX15041ETE+T
• Description: IC REG DC-DC PWM STEP DN 16-TQFN
• Manufacturer: Maxim Integrated Products
• Type: Step-Down (Buck)r

Specifications of MAX15041ETE+T

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 0.6 ~ 25.2 V
• Current - Output: 3A
• Frequency - Switching: 350kHz
• Voltage - Input: 4.5 ~ 28 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-TQFN Exposed Pad
• Power - Output: 1.67W
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

For R
further simplified as follows:
where V
3) Select C
therefore:
4) If the ESR output zero is located at less than one-half
therefore:
If the ESR zero exceeds 1/2 the switching frequency,
use the following equation:
therefore:
The downside of C
system phase margin. Care should be taken to guarantee
Step-Down DC-DC Regulator with Internal Switches
desired first system zero, f
phase margin. Typically, setting f
f
the switching frequency use the (optional) sec-
ondary compensation capacitor, C
as follows:
CO
LOAD
provides sufficient phase margin.
2
FB
is equal to 0.606V.
much greater than ESR, the equation can be
Low-Cost, 3A, 4.5V to 28V Input, 350kHz, PWM
C
R
C
1
C
CC C
. C
f
P
f
Z
R
3
C
C
1
C
C
______________________________________________________________________________________
V
CC
CC
CC
V
OUT
C
FB
is determined by selecting the
2
2
f
is that it detracts from the overall
P
2
3
2
C
C
C R
OUT
1
2
1
CC C
C C
g
f
Z
f
CO
f
MV
SW
2
R
5
Z1
R
2
f
C
CO
, based on the desired
2
ESR
R
G
f
R
CO
C
MOD
5
f
C
SW
C
2
Z1
OUT
C
CC
OUT
1
below 1/5th of
, to cancel it,
ESR
this third-pole placement is well beyond the desired
crossover frequency, minimizing its interaction with the
system loop response at crossover. If C
10pF, it can be neglected in these calculations.
The soft-start feature ramps up the output voltage slow-
ly, reducing input inrush current during startup. Size the
C
using:
I
put feedback voltage threshold, is 0.606V (typ). When
using large C
current limit may trigger during the soft-start period. To
ensure the correct soft-start time, t
enough to satisfy:
I
limit value.
The MAX15041 is available in a thermally enhanced
TQFN package and can dissipate up to 1.666W at T
+70°C. The exposed pad should be connected to
SGND externally, preferably soldered to a large ground
plane to maximize thermal performance. When the die
temperature exceeds +155°C, The thermal-shutdown
protection is activated (see the Thermal-Shutdown
Protection section).
Careful PCB layout is critical to achieve clean and sta-
ble operation. It is highly recommended to duplicate
the MAX15041 evaluation kit layout for optimum perfor-
mance. If deviation is necessary, follow these guide-
lines for good PCB layout:
1) Connect input and output capacitors to the power
SS
HSCL_MIN
SS
ground plane; connect all other capacitors to the
signal ground plane.
, the soft-start current, is 5µA (typ) and V
capacitor to achieve the desired soft-start time t
C
SS
is the minimum high-side switch, current-
OUT
C
OUT
capacitance values, the high-side
C
Setting the Soft-Start Time
SS
(
I
HSCL MIN
I
SS
V
_
FB
V
t
OUT
Power Dissipation
SS
Layout Procedure
SS
, choose C
I
OUT
I
CC
SS
is smaller than
)
FB
V
FB
, the out-
SS
large
A
15
SS
=