LTM4600HVEV#PBF Linear Technology, LTM4600HVEV#PBF Datasheet - Page 10

• Manufacturer Part Number: LTM4600HVEV#PBF
• Description: IC DC/DC UMODULE 10A 104-LGA
• Manufacturer: Linear Technology
• Series: µModuler
• Type: Point of Load (POL) Non-Isolatedr

Specifications of LTM4600HVEV#PBF

• Design Resources: LTM4600HV Spice Model
• Output: 0.6 ~ 5 V
• Number Of Outputs: 1
• Power (watts): 50W
• Mounting Type: Surface Mount
• Voltage - Input: 4.5 ~ 28 V
• Package / Case: 104-LGA
• 1st Output: 0.6 ~ 5 VDC @ 10A
• Size / Dimension: 0.59" L x 0.59" W x 0.11" H (15mm x 15mm x 2.8mm)
• Power (watts) - Rated: 50W
• Operating Temperature: -40°C ~ 85°C
• Efficiency: 92%
• Dc To Dc Converter Type: Step Down
• Pin Count: 104
• Input Voltage: 28V
• Output Voltage: 0.6 to 5V
• Switching Freq: 850KHz
• Output Current: 10A
• Package Type: LGA
• Output Type: Adjustable
• Switching Regulator: Yes
• Mounting: Surface Mount
• Input Voltage (min): 4.5V
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• 3rd Output: -
• 2nd Output: -
• Lead Free Status / Rohs Status: Compliant

APPLICATIONS INFORMATION
LTM4600HV
should be placed directly adjacent the module input pins
in the PCB layout to minimize the trace inductance and
high frequency AC noise.
Output Capacitors
The LTM4600HV is designed for low output voltage ripple.
The bulk output capacitors C
effective series resistance (ESR) to meet the output voltage
ripple and transient requirements. C
tantalum capacitor, low ESR polymer capacitor or ceramic
capacitor (X5R or X7R). The typical capacitance is 200μF
if all ceramic output capacitors are used. The internally
optimized loop compensation provides suffi cient stability
margin for all ceramic capacitors applications. Additional
output fi ltering may be required by the system designer,
if further reduction of output ripple or dynamic transient
spike is required. Refer to Table 2 for an output capaci-
tance matrix for each output voltage droop, peak to peak
deviation and recovery time during a 5A/μs transient with
a specifi c output capacitance.
Fault Conditions: Current Limit and Over current
Foldback
The LTM4600HV has a current mode controller, which
inherently limits the cycle-by-cycle inductor current not
only in steady state operation, but also in transient.
To further limit current in the event of an over load condi-
tion, the LTM4600HV provides foldback current limiting.
If the output voltage falls by more than 50%, then the
maximum output current is progressively lowered to about
one sixth of its full current limit value.
10
OUT
is chosen with low enough
OUT
can be low ESR
Soft-Start and Latchoff with the RUN/SS pin
The RUN/SS pin provides a means to shut down the
LTM4600HV as well as a timer for soft-start and over-
current latchoff. Pulling the RUN/SS pin below 0.8V puts
the LTM4600HV into a low quiescent current shutdown
(I
current source to charge up the timing capacitor C
Inside LTM4600HV, there is an internal 1000pF capaci-
tor from RUN/SS pin to ground. If RUN/SS pin has an
external capacitor C
starting is about:
When the voltage on RUN/SS pin reaches 1.5V, the LT-
M4600HV internal switches are operating with a clamping
of the maximum output inductor current limited by the
RUN/SS pin total soft-start capacitance. As the RUN/SS pin
voltage rises to 3V, the soft-start clamping of the inductor
current is released.
V
There are restrictions in the maximum V
down ratio that can be achieved for a given input voltage.
These contraints are shown in the Typical Performance
Characteristics curves labeled “V
Ratio”. Note that additional thermal de-rating may apply.
See the Thermal Considerations and Output Current De-
Rating sections of this data sheet.
IN
Q
t
≤ 75μA). Releasing the pin allows an internal 1.2μA
DELAY
to V
OUT
=
Stepdown Ratios
1.2μA
1.5V
• (C
SS_EXT
SS_EXT
to ground, the delay before
+ 1000pF)
IN
to V
IN
OUT
to V
Stepdown
OUT
4600hvfd
step
SS
.