Datasheet

LXDC3EP series
Micro DC-DC converter
6
Dec 2014
0
50
100
150
200
250
300
350
400
0 500 1000 1500
Power Dissipation [mW]
Iout [mA]
Io - Loss Charateristics (Vin=5.0V, Vo=3.3V)
PWM
PWM/PFM
Parameter Symbol Condition Min. Typ. Max. Unit
SW Frequency Freq - 4 - MHz
Over Current
Protection
OCP 1000 1200 1700 mA
Start -up Time Ton - 170 - usec
(*1)The above characteristics are tested using the application circuit in section 8
6-3 Thermal and Current De-rating Information
The following figure shows an example of the power dissipation and temperature rise characteristics. These
data are measured on Murata’s evaluation board of this device at a no air-flow condition.
The output current of the device may need to be de-rated if it is operated in high ambient temperature or in an
application that requires continuous power delivery. The amount of current de-rating is highly dependent on the
environmental thermal conditions, e.g., PCB design, nearby components, or effective air flow. Care should
especially be taken in applications where the device temperature exceeds 85
o
C.
The case temperature of the device must be kept lower than the maximum rating of 125
o
C. It is generally
recommended to take an appropriate de-rating of the IC temperature for reliable operation. A general de-rating
for the temperature of the semiconductor is 80%.
MLCC capacitors’ reliability and lifetime are also dependent on temperature and applied voltage stress. Higher
temperature and/or higher voltage cause shorter lifetime of the MLCC, and the degradation can be described by
the Arrhenius model. The most critical parameter of the degradation is IR (Insulation Resistance). The below
figure shows MLCC’s B1 life based on a failure rate reaching 1%. It should be noted that wear-out mechanisms
in the MLCC capacitor is not reversible but cumulative over time.