TABLE 1. Typical Values of Case-to-Heatsink

Thermal Resistance (˚C/W) (Data from AAVID Eng.)

Silicone grease

1.0

Dry interface

1.3

Mica with grease

1.4

TABLE 2. Typical Values of Case-to-Heatsink

Thermal Resistance (˚C/W) (Data from Thermalloy)

Thermasil III

1.3

Thermasil II

1.5

Thermalfilm (0.002) with grease

2.2

Note 3: Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.

Note 4: Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested separately for load regulation in the load

ranges 0.1 mA–1 mA and 1 mA–250 mA. Changes in output voltage due to heating effects are covered by the thermal regulation specification.

Note 5: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV below the value measured with a 1V differential.

Note 6: Ground pin current is the regulator quiescent current. The total current drawn from the source is the sum of the load current plus the ground pin current.

Note 7: 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

Note 8: When used in dual-supply systems where the regulator load is returned to a negative supply, the output voltage must be diode-clamped to ground.

Note 9: Connect a 0.1µF capacitor from the output to the feedback pin.

Note 13: Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the nominal reference voltage measured at

Note 14: Human body model, 200pF discharged through 1.5k

Ω.

Typical Performance Characteristics

Quiescent Current

DS011128-12

Quiescent Current

DS011128-13

Ground Pin Current vs Load

DS011128-14

Ground Pin Current

DS011128-15

Ground Pin Current

DS011128-16

Output Noise Voltage

DS011128-17

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