MIC2940 Micrel Semiconductor, MIC2940 Datasheet - Page 4

• Manufacturer Part Number: MIC2940
• Description: 1.25A Low-Dropout Voltage Regulator Preliminary Information
• Manufacturer: Micrel Semiconductor

MIC2940A/2941A
Electrical Characteristics
Parameter
Reference Voltage
Reference Voltage
Adjust Pin
Bias Current
Reference Voltage
Temperature
Coefficient
Adjust Pin Bias
Current Temperature
Coefficient
Shutdown Input
Input Logic Voltage
Shutdown Pin
Input Current
Regulator Output
Current in Shutdown
Note 1:
apply when operating the device outside of its rated operating conditions. The maximum allowable power dissipation is a function of the
maximum junction temperature, T
allowable power dissipation at any ambient temperature is calculated using: P
power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown.
Note 2:
Note 3:
heating effects are covered by the thermal regulation specification.
Note 4:
measured at 1V differential. At low values of programmed output voltage, the minimum input supply voltage of 4.3V over temperature must
be taken into account.
Note 5:
the ground pin current.
Note 6:
normal output voltage.
Note 7:
load or line regulation effects. Specifications are for a 200mA load pulse at V
Note 8:
Note 9:
Note 10: 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 11: Maximum positive supply voltage of 60 V must be of limited duration (< 100 ms) and duty cycle ( 1%). The maximum continuous
supply voltage is 26V.
MIC2940A/2941A
Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not
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. Changes in output voltage due to
Dropout Voltage is defined as the input to output differential at which the output voltage drops 100 mV below its nominal value
Ground pin current is the regulator quiescent current. The total current drawn from the source is the sum of the load current plus
The MIC2940A features fold-back current limiting. The short circuit (V
Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding
V
Circuit of Figure 3 with R1
REF
V
OUT
(V
(Note 8)
Low (ON)
High (OFF)
V
V
(Note 10)
Conditions
SHUTDOWN
SHUTDOWN
IN
– 1 V), 4.3V
J (MAX)
= 2.4V
= 26V
, the junction-to-ambient thermal resistance,
150k . V
(MIC2941A Only)
V
IN
SHUTDOWN
26V, 5mA < I
2 V and V
L
1.25A, T
4
IN
26 V,V
J
IN
(MAX)
T
OUT
= 20V (a 4W pulse) for T = 10ms.
J MAX.
OUT
= 0V) current limit is less than the maximum current with
= (T
JA
= 0.
, and the ambient temperature, T
J(MAX)
– T
A
) /
1.223
1.210
1.204
Min
2.0
JA.
Exceeding the maximum allowable
Typical
1.235
450
0.1
1.3
20
20
30
3
1.247
1.260
1.266
Max
100
600
750
0.7
40
60
50
30
60
A
. The maximum
June 1999
ppm/ C
V max
nA/ C
Micrel
Units
nA
V
V
V
A
A
A