MIC5219
Note 1:
Micrel
Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when
operating the device outside of its operating ratings. The maximum allowable power dissipation is a function of the maximum junction
temperature, T
J(max)
, the junction-to-ambient thermal resistance,
θ
JA
, and the ambient temperature, T
A
. The maximum allowable power
dissipation at any ambient temperature is calculated using: P
D(max)
= (T
J(max)
– T
A
)
÷ θ
JA
. Exceeding the maximum allowable power dissipa-
tion will result in excessive die temperature, and the regulator will go into thermal shutdown. See Table 1 and the “Thermal Considerations”
section for details.
Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load
range from 100µA to 500mA. Changes in output voltage due to heating effects are covered by the thermal regulation specification.
Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1V
differential.
Ground pin current is the regulator quiescent current plus pass transistor base current. The total current drawn from the supply is the sum of
the load current plus the ground pin current.
V
EN
is the voltage externally applied to devices with the EN (enable) input pin.
Thermal regulation is defined as the change in output voltage at a time “t” after a change in power dissipation is applied, excluding load or line
regulation effects. Specifications are for a 500mA load pulse at V
IN
= 12V for t = 10ms.
C
BYP
is an optional, external bypass capacitor connected to devices with a BYP (bypass) or ADJ (adjust) pin.
Note 2:
Note 3:
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Note 5:
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Note 7:
Note 8:
April 2001
5
MIC5219
MICREL [ MICREL SEMICONDUCTOR ]
