Datasheet

ELECTRICAL CHARACTERISTICS:
PARAMETER TEST CONDITIONS UC1526 / UC2526 UC3526 UNITS
MIN TYP MAX MIN TYP MAX
Oscillator Section (Note 5)
Initial Accuracy T
J = + 25°C ±3 ±8 ±3 ±8%
Voltage Stability +V
IN = 8 to 35V 0.5 1 0.5 1 %
Temperature Stability Over Operating T
J 710 3 5%
Minimum Frequency R
T = 150kΩΩ, CT = 20µµF11Hz
Maximum Frequency R
T = 2kΩΩ, CT = 1.0nF 400 400 kHz
Sawtooth Peak Voltage +V
IN = 35V 3.0 3.5 3.0 3.5 V
Sawtooth Valley Voltage +V
IN = 8V 0.5 1.0 0.5 1.0 V
Error Amplifier Section (Note 6)
Input Offset Voltage R
S ≤≤ 2kΩΩ 25 210mV
Input Bias Current -350 -1000 -350 -2000 nA
Input Offset Current 35 100 35 200 nA
DC Open Loop Gain R
L ≥ 10MΩΩ 64 72 60 72 dB
HIGH Output Voltage V
PIN1-VPIN2 ≥≥ 150mV, ISOURCE =
100µµA
3.6 4.2 3.6 4.2 V
LOW Output Voltage V
PIN2-VPIN1 ≥≥ 150mV, ISINK = 100µµA 0.2 0.4 0.2 0.4 V
Common Mode Rejection Rs ≤ 12kΩ 70 94 70 94 dB
Supply Voltage Rejection +V
IN = 12 to 18V 66 80 66 80 dB
PWM Comparator (Note 5)
Minimum Duty Cycle V
COMPENSATION = +0.4V 0 0 %
Maximum Duty Cycle V
COMPENSATION = +3.6V 45 49 45 49 %
Digital Ports (
SYNC, SHUTDOWN, and RESET)
HIGH Output Voltage I
SOURCE =40µµA 2.4 4.0 2.4 4.0 V
LOW Output Voltage I
SINK = 3.6mA 0.2 0.4 0.2 0.4 V
HIGH Input Current V
IH = +2.4V -125 -200 -125 -200 µA
LOW Input Current V
IL = +0.4V -225 -360 -225 -360 µA
Current LImit Comparator (Note 7)
Sense Voltage R
S ≤≤ 50ΩΩ 90 100 110 80 100 120 mV
Input Bias Current -3 -10 -3 -10 µA
Soft-Start Section
Error Clamp Voltage
RESET = +0.4V 0.1 0.4 0.1 0.4 V
Cs Charging Current
RESET =+2.4V 50 100 150 50 100 150 µA
Output Drivers (Each Output) (Note 8)
HIGH Output Voltage I
SOURCE = 20mA 12.5 13.5 12.5 13.5 V
I
SOURCE = 100mA 12 13 12 13 V
LOW Output Voltage I
SINK = 20mA 0.2 0.3 0.2 0.3 V
I
SINK = 100mA 1.2 2.0 1.2 2.0 V
Collector Leakage V
C = 40V 50 150 50 150 µA
Rise Time CL = 1000pF 0.3 0.6 0.3 0.6 µs
Fall Time CL = 1000pF 0.1 0.2 0.1 0.2 µs
Power Consumption (Note 9)
Standby Current SHUTDOWN
____________
=
+0.4V 18 30 18 30 mA
+VIN = 15V, and over operating ambient temperature, unless otherwise
specified, TA = TJ.
UC1526
UC2526
UC3526
Note 4: I L = 0mA.
Note 5: F
OSC = 40kHz (R T = 4.12k Ω ± 1%, C T = 0.1 µ F ± 1%,
R
D = 0 Ω )
Note 6: V
CM = 0 to +5.2V
Note 8: V
C = +15V
Note 9: +V
IN = +35V, R T = 4.12k Ω
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