AS2955/56/57
(Continued)
Typ.
AS2955/56/57A
Min Max
AS2955/56/57A
AS2955/56/57B
PARAMETER
CONDITIONS
(Note 2)
Min
Max
UNITS
Typ.
1.235
AS2955/56/57B
Adjustable Versions only
Reference Voltage
1.210
1.200
1.185
1.260
1.200
1.990
1.185
1.270
1.280
1.285
V
1.270
Reference Voltage
Feedback Pin Bias Current
Over Temperature (Note 6)
(Note 7)
1.285
V
20
40
60
80
NA
60
Reference Voltage Temperature
Coefficient
ppm/°C
nA/°C
50
Feedback Pin Bias Current
Temperature Coefficient
0.1
Error Comparator
Output Leakage Current
V
0H = 30V
0.01
150
60
1.00
2.00
250
400
1.00
2.00
250
400
µA
mV
mV
mV
mV
Output Low Voltage
Upper Threshold Voltage
Lower Threshold Voltage
Hysteresis
VIN = 4.5V
I0L = 400µA
(Note 8)
40
25
40
25
(Note 8)
(Note 8)
75
95
140
95
140
15
Shutdown Input
Input logic Voltage
Low (Regulator ON)
High (Regulator OFF)
VS = 2.4V
V
1.3
30
2.0
0.7
50
100
600
750
2.0
0.7
90
Shut down Pin Input Current
µA
150
800
1000
15
VS = 30V
450
3
Regulator Output Current in Shutdown
10
20
µA
25
Note 1: Output or reference voltage temperature coefficients defined as the worst case voltage change divided by the total temperature range.
Note 2: Unless otherwise specified all limits are guaranteed for Tj = 25°C, VIN = 6V, IL = 100µA and CL = 1µF. Additional conditions for the 8-pin versions are
feedback tied to 5V tap and output tied to output sense (VOUT = 5V) and VSHUTDOWN ≤ 0.8V.
Note 3: 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 under the specification for thermal regulation.
Note 4: Line regulation for the AS2955/56/57 is tested at 150°C for IL = 1 mA. For IL = 100µA and TJ = 125°C, line regulation is guaranteed by design to 0.2%. See
typical performance characteristics for line regulation versus temperature and load current.
Note 5: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV 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: VREF ≤VOUT ≤ (Vin - 1V), 2.3 ≤Vin≤30V, 100µA≤IL≤ 250 mA, TJ ≤ TJMAX
.
Note 7: 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 = VOUT/VREF = (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 95 mV x 5V/1.235 = 384 mV. Thresholds remain constant as a percent of VOUT as
V
OUT is varied, with the dropout warning occurring at typically 5% below nominal, 7.5% guaranteed.
Note 8: VSHUTDOWN ≥ 2V, VIN ≤ 30V, VOUT =0, Feedback pin tied to 5V Tap.
Note 9: 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 (S) package is 160°C/W.
Rev. 10/6/00
SIPEX [ SIPEX CORPORATION ]
