MIC2950/2951
Parameter
Shutdown Input Logic Voltage
Condition
MIC295x-02/-05 (±0.5%)
Low
High
MIC295x-03/-06 (±1%)
Low
High
MIC2951-3.3 (±1%)
Low
High
MIC2951-4.8 (±1%)
Low
High
Shutdown Input Current
V
SHUTDOWN
= 2.4V
V
SHUTDOWN
= 30V
Regulator Output Current
in Shutdown
Note 1.
Note 2.
Note 3.
Note 4.
Micrel
Min
Typ
1.3
0.7
2.0
1.3
0.7
2.0
1.3
0.7
2.0
1.3
0.7
2.0
30
450
3
50
100
600
750
10
20
Max
Units
V
V
V
V
V
V
V
V
V
V
V
V
µA
µA
µA
µA
µA
µA
Note 7
Exceeding the absolute maximum rating may damage the device.
The device is not guaranteed to function outside its operating rating.
Devices are ESD sensitive. Handling precautions are recommended.
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.
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. Junction-to-ambient thermal resistance for the MM8™ (MM) is 250°C/W.
The maximum positive supply voltage of 60V must be of limited duration (≤100ms) and duty cycle (≤1%). The maximum continuous supply
voltage is 30V.
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.
V
SHDN
≥
2V, V
IN
≤
30 V, V
OUT
= 0, with the FB pin connected to TAP.
Additional conditions for 8-pin devices are V
FB
= 5V, TAP and OUT connected to SNS (V
OUT
= 5V) and V
SHDN
≤
0.8V.
Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
Note 5.
Note 6.
Note 7.
Note 8.
Note 9.
Note 10.
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 11.
Line regulation for the MIC2951 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.
Note 12.
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 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.
V
REF
≤
V
OUT
≤
(V
IN
– 1 V), 2.3V
≤
V
IN
≤
30V, 100µA < I
L
≤
150mA, T
J
≤
T
JMAX
.
Note 15.
Comparator thresholds are expressed in terms of a voltage differential at the FB 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.
3-54
February 1999
MICREL [ MICREL SEMICONDUCTOR ]
