MAX15017BATX+ Maxim Integrated Products, MAX15017BATX+ Datasheet - Page 22

• Manufacturer Part Number: MAX15017BATX+
• Description: IC DC/DC CONV 1A 36-TQFN-EP
• Manufacturer: Maxim Integrated Products
• Type: Step-Down (Buck)r

Specifications of MAX15017BATX+

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 2
• Voltage - Output: 1.26 ~ 32 V
• Current - Output: 1A
• Frequency - Switching: 135kHz ~ 500kHz
• Voltage - Input: 7.5 ~ 40 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 36-TQFN Exposed Pad
• Power - Output: 2.1W
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

1A, 4.5V to 40V Input Buck Converters with
50mA Auxiliary LDO Regulators
power dissipated due to the RMS current through the
internal power MOSFET (P
dissipated in the package must be limited such that the
junction temperature does not exceed its absolute max-
imum rating of +150°C at maximum ambient tempera-
ture. Calculate the power lost in the MAX15014–
MAX15017 using the following equations:
The power loss through the switch:
Figure 6. MAX15015/MAX15016 Typical Application Circuit (4.5V to 40V Input Operation)
22
I
I
I
P
D
RMS MOSFET
PK
DC
______________________________________________________________________________________
MOSFET
=
=
=
V
PGND
_
OUT
V
I
I
OUT
OUT
IN
C6
R6
=
SGND
+
−
(
I
RMS MOSFET
C
∆
∆
SS
I
I
=
P P
P P
2
2
−
−
_
D
3
R3
R4
×
⎡
⎣ ⎢
I
2
C
PK
5V TO 40V
REG
MOSFET
R5
)
2
+
×
4.5V TO 40V
V
C8
(
R
I
IN
PK
0.47µF
ON
1Ω
C
C7
). The total power
×
V
F
IN
I
DC
)
+
I
2
C
DC
COMP
FB
EN_SW
EN_SYS
C+
C-
SS
SYNC
REG
DVREG
IN_LDO
⎤
⎦ ⎥
IN_LDO
PGND
MAX15015
MAX15016
IN_SW
R
(see the Electrical Characteristics ).
The power loss due to switching the internal MOSFET:
t
MOSFET measured at LX.
The power loss due to the switching supply current (I
The power loss due to the LDO regulator:
The total power dissipated in the device will be:
R
C
ON
IN_SW
and t
SGND
DRAIN
is the on-resistance of the internal power MOSFET
LDO_OUT
P
SET_LDO
F
P
LDO
RESET
TOTAL
are the rise and fall times of the internal power
BST
CT
LX
D1
P
=
SW
C
(
DRAIN
V
= P
IN LDO
P
=
Q
_
V
MOSFET
=
D2
IN
C
BST
V
×
IN SW
I
−
OUT
_
V
LDO OUT
L
+ P
C
CT
×
×
(
_
4
I
t
SW
SW
R
10kΩ
+
+ P
t
F
)
×
)
V
V
Q
OUT1
OUT2
×
I
C
C
LDO OUT
OUT
LDO_OUT
f
+ P
SW
AT 1A
AT 50mA
_
LDO
SW
):