MIC5316-F4CYMT TR Micrel Inc, MIC5316-F4CYMT TR Datasheet - Page 11

• Manufacturer Part Number: MIC5316-F4CYMT TR
• Description: Low Vin/Vout Dual 300mA LDO With VSC + POR In 2.5mm X 2.5mm TMLFr
• Manufacturer: Micrel Inc

Specifications of MIC5316-F4CYMT TR

• Regulator Topology: Positive Fixed
• Voltage - Output: 1.5V, 1.2/1V
• Voltage - Input: 1.7 ~ 5.5 V
• Voltage - Dropout (typical): 0.085V @ 300mA
• Number Of Regulators: 2
• Current - Output: 300mA
• Current - Limit (min): 350mA
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 12-TMLF®
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 576-3145-2

Thermal Considerations
The MIC5316 is designed to provide 300mA of
continuous current for both outputs in a very small
package. Maximum ambient operating temperature can
be calculated based upon the output current and the
voltage drop across the part. Given that the input voltage
is 1.8V, the output voltage is 1.5V for V
V
The actual power dissipation of the regulator circuit can
be determined using the equation:
P
Because this device is CMOS and the ground current is
typically <100µA over the load range, the power
dissipation contributed by the ground current is <1% and
can be ignored for this calculation.
P
To
temperature of the package, use the junction-to-ambient
thermal resistance of the device and the following basic
equation:
Micrel, Inc.
July 2008
OUT2
D
D
= (V
= (1.8V – 1.5V) × 300mA + (1.8V – 1.0V) × 300mA
determine
and the output current = 300mA for each output.
IN
P
P
– V
D
D(MAX)
= 0.33W
OUT1
=
) I
the
⎛
⎜
⎜
⎝
OUT1
T
J(MAX)
+ (V
θ
maximum
JA
−
IN
T
– V
A
⎞
⎟
⎟
⎠
OUT2
ambient
) I
OUT2
OUT1
+ V
, 1.0V for
BIAS
operating
I
GND
11
T
the die. The junction-to-ambient thermal resistance for
the minimum footprint, is θ
Substituting P
operating temperature will give the maximum operating
conditions for the regulator circuit.
The maximum power dissipation must not be exceeded
for proper operation.
For example, when operating the MIC5316-F5CYMT at
an input voltage of 1.8V and 300mA, loads at each
output with a minimum footprint layout, the maximum
ambient operating temperature T
follows:
For a full discussion of heat sinking and thermal effects
on voltage regulators, refer to the “Regulator Thermals”
section of Micrel’s Designing with Low-Dropout Voltage
Regulators handbook. This information can be found on
Micrel's website at:
http://www.micrel.com/_PDF/other/LDOBk_ds.pdf
J(max)
= 125°C, the maximum junction temperature of
0.33W = (125°C – T
T
A
= 101.9°C
D
for P
D(max)
JA
and solving for the ambient
A
= 70°C/W.
)/(70°C/W)
A
can be determined as
M9999-070208-A
MIC5316