LTM4602HVEV#PBF Linear Technology, LTM4602HVEV#PBF Datasheet - Page 18

• Manufacturer Part Number: LTM4602HVEV#PBF
• Description: IC DC/DC UMODULE 6A 104-LGA
• Manufacturer: Linear Technology
• Series: µModuler
• Type: Point of Load (POL) Non-Isolatedr

Specifications of LTM4602HVEV#PBF

• Design Resources: LTM4602HV Spice Model
• Output: 0.6 ~ 5 V
• Number Of Outputs: 1
• Power (watts): 30W
• Mounting Type: Surface Mount
• Voltage - Input: 4.5 ~ 28 V
• Package / Case: 104-LGA
• 1st Output: 0.6 ~ 5 VDC @ 6A
• Size / Dimension: 0.59" L x 0.59" W x 0.11" H (15mm x 15mm x 2.8mm)
• Power (watts) - Rated: 30W
• Operating Temperature: -40°C ~ 85°C
• Efficiency: 92%
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• 3rd Output: -
• 2nd Output: -

APPLICATIO S I FOR ATIO
LTM4602HV
Using the frequency = (I
I
calculated from 12V input was 103µA, so a resistor from
f
57µA, sets the adequate I
range for the higher duty cycle conversion of 12V to
5V. Input voltage range is limited to 8V to 16V. Higher
input voltages can be used without the 15k on f
The inductor ripple current gets too high above 16V or
below 8V.
Equations for setting frequency: V
t
~450kHz frequency or 2.22µs period is chosen. Frequency
range is about 450kHz to 650kHz from 4.5V to 7V input.
t
band.
18
ON
ADJ
OFF
ON
I
frequency = (I
DC = duty cycle, duty cycle is (V
t = t
switching period; t = 1/frequency
t
t
t
ON
ON
ON
OFF
and t
= (1MHz • 2.4V • 10pF) • (1/0.41) ≅ 58µA. I
must be greater than 400ns, or t – t
to ground = (0.7V/15k) = 46µA. 103µA – 46µA =
= (V
= DC • t
= 0.66 • 2.22µs ≅ 1.46µs
= 2.22µs – 1.46µs ≅ 760ns
ON
OFF
IN
+ t
are above the minimums with adequate guard
– 0.7V)/110k; for 5V input, I
OFF
, t
ON
ON
U
/[2.4V • 10pF]) • (DC) = 1.07MHz;
5V TO 3.3V AT 5A WITH f
LTM4602HV MINIMUM ON-TIME = 100ns
LTM4602HV MINIMUM OFF-TIME = 400ns
= on-time, t
ON
RUN/SOFT-START
C3
10µF
25V
ON
U
/[2.4V • 10pF]) • (DC), solve for
current for proper frequency
4.5V TO 7V
C1
10µF
25V
OUT
V
IN
OUT
OFF
W
ADJ
= 3.3V
/V
= off-time of the
ON
IN
= 30.1k
EXTV
FCB
RUN/SS
COMP
ON
)
> 400ns.
= 39µA
CC
SGND
ON
V
U
LTM4602HV
IN
current
5V to 3.3V at 5A
ADJ
PGND
f
ADJ
.
PGOOD
V
4602HV F23
V
OSET
SV
30.1k
C1, C3: TDK C3216X5R1E106MT
C2: TAIYO YUDEN, JMK316BJ226ML
C4: SANYO POS CAP, 6TPE330MIL
OUT
R1
IN
Using the frequency = (I
for I
current calculated from 5V input was 39µA, so a resistor
from f
= 16µA, sets the adequate I
range for the higher duty cycle conversion of 5V to 3.3V.
Input voltage range is limited to 4.5V to 7V. Higher input
voltages can be used without the 30.1k on f
tor ripple current gets too high above 7V, and the 400ns
minimum off-time is limited below 4.5V.
Therefore, at 3.3V output, a 30.1k resistor is recommended
to add from pin f
between 4.5V to 7V. However, this resistor needs to be
removed to avoid high inductor ripple current when the
input voltage is more than 7V. Similarly, for 5V output, a
15k resistor is recommended to adjust the frequency when
the input voltage is between 8V to 16V. This 15k resistor
is removed when the input voltage becomes higher than
16V. Please refer to the Typical Performance curve V
V
In 12V to 3.3V and 24V to 3.3V applications, if a 35k
resistor is added from the f
effi ciency gain will be achieved as shown in the 12V and
24V effi ciency graphs shown in the Typical Characteris-
tics. This is due to lowering the transition losses in the
power MOSFETs by reducing the switching frequency
from 1.3mHz to 1mHz.
OUT
ON
OPEN DRAIN
Step-Down Ratio.
ADJ
= (450kHz • 2.4V • 10pF) • (1/0.66) ≅ 16µA. I
to ground = (0.7V/30.1k) = 23µA. 39µA – 23µA
C5
100pF
3.3V AT 5A
R
22.1k
1%
SET
ADJ
V
OUT
to ground when the input voltage is
C2
22µF
EFFICIENCY = 92%
ON
ON
/[2.4V • 10pF]) • (DC), solve
ADJ
+
current for proper frequency
pin to ground, then a 2%
C4
330µF
6.3V
ADJ
. The induc-
4602hvf
IN
ON
to