LP2950 Datasheet, PDF (5/14 Pages) National Semiconductor (TI) – Series of Adjustable Micropower Voltage Regulators

LP2950/2951
Micrel
Parameter
Shutdown Input Current
Regulator Output Current
in Shutdown
Condition
V_SHUTDOWN = 2.4V
V_SHUTDOWN = 30V
Note 11
Min Typ Max Units
30
50
µA
100
µA
450 600
µA
750
µA
3
10
µA
20
µA
Note 1: Boldface limits apply at temperature extremes.
Note 2: Unless otherwise specified all limits guaranteed for T_J = 25°C, V_IN = 6V, I_L = 100µA and C_L = 1µF. Additional conditions for the 8-pin versions
are Feedback tied to 5V Tap and Output tied to Output Sense (V_OUT = 5V) and V_SHUTDOWN ≤ 0.8V.
Note 3: Guaranteed and 100% production tested.
Note 4: Guaranteed but not 100% production tested. These limits are not used to calculate outgoing AQL levels.
Note 5: Dropout voltage is defined as the input to output differential at which the output voltage drops 100mV below its nominal value measured at 1V
differential. At very low values of programmed output voltage, the minimum input supply voltage of 2V (2.3V over temperature) must be taken
into account.
Note 6:
Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the nominal reference voltage
measured at 6V input. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = V_OUT /V_REF =
(R1 + R2)/R2. For example, at a programmed output voltage of 5V, the Error output is guaranteed to go low when the output drops by
95mV x 5V/1.235V = 384mV. Thresholds remain constant as a percent of V_OUT as V_OUT is varied, with the dropout warning occurring at
typically 5% below nominal, 7.5% guaranteed.
Note 7: V_REF ≤ V_OUT ≤ (V_IN – 1 V), 2.3V ≤ V_IN ≤ 30V, 100µA < I_L ≤ 100mA, T_J ≤ T_JMAX.
Note 8: The junction-to-ambient thermal resistance of the TO-92 package is 180°C/W with 0.4” leads and 160°C/W with 0.25” leads to a PC board.
3
The thermal resistance of the 8-pin DIP package is 105°C/W junction-to-ambient when soldered directly to a PC board. Junction-to-ambient
thermal resistance for the SOIC (M) package is 160°C/W.
Note 9: May exceed input supply voltage.
Note 10: When used in dual-supply systems where the output terminal sees loads returned to a negative supply, the output voltage should be diode-
clamped to ground.
Note 11: V_SHUTDOWN ≥ 2V, V_IN ≤ 30 V, V_OUT = 0, with Feedback pin tied to 5V Tap.
Note 12: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
Note 13: 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 50mA load pulse at V_IN = 30V (1.25W pulse) for t = 10ms.
Note 14: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating
effects are covered in the specification for thermal regulation.
Note 15: Line regulation for the LP2951 is tested at 150°C for I_L = 1mA. For I_L = 100µA and T_J = 125°C, line regulation is guaranteed by design to
0.2%. See Typical Performance Characteristics for line regulation versus temperature and load current.
February 1999
3-39