Datasheet
UC1835 UC1836
UC2835 UC2836
UC3835 UC3836
PARAMETER TEST CONDITIONS MIN. TYP. MAX. UNITS
Regulating Voltage and Error Amplifier (UC1836 Family Only)
Regulating Level at V
OUT Sense (VREG) Driver Current = 10mA, TJ = 25°C 2.47 2.5 2.53 V
Over Temperature 2.45 2.55 V
Line Regulation +V
IN = 5.2V to 35V 6.0 20 mV
Load Regulation Driver Current = 0 to 250mA 3.0 15 mV
Bias Current at V
OUT Sense VOUT Sense =2.5V -1.0 -0.2 µA
Error Amp Transconductance ±100µA at Compensation/Shutdown Pin 0.8 1.3 2.0 mS
Maximum Compensation Output Current Sink or Source, Driver Source Open 90 200 260 µA
Driver
Maximum Current 250 500 mA
Saturation Voltage Driver Current = 250mA, Driver Sink 2.0 2.8 V
Pull-Up Current at Driver Sink Compensation/Shutdown=0.45V 140 250 300 µA
Driver Sink Leakage In UVLO 10 µA
In Reverse Voltage (UC1835 Family Only) 10 µA
Thermal Shutdown 165 °C
Foldback Current Limit
Current Limit Levels at Sense Resistor Out V
OUT Sense = (0.99) VREG 2.2 2.5 2.8 A
V
OUT Sense = (0.5) VREG 1.3 1.5 1.7 A
V
OUT Sense = 0V 0.25 0.4 0.55 A
Current Limit Amp Tansconductance ±100µA at Compensation/Shutdown,
V
OUT Sense = (0.9) VREG
12 24 42 mS
Limiting Voltage at Current Limit (-)
(Note 2)
V
OUT Sense = (0.9) VREG
Volts Below +VIN, TJ = 25°C
80 100 140 mV
Sense Resistor Value (Note 3) V
OUT
Sense = (0.9) VREG,
IOUT = IA, TJ = 25°C
40 mΩ
Note 2: This voltage has a positive temperature coefficient of approximately 3500ppm/°C.
Note 3: This resistance has a positive temperature coefficient of approximately 3500ppm/°C.
The total resistance from Pin 1 to Pin 8 will include an additional 60 to 100m
Ω
of package resistance.
ELECTRICAL CHARACTERISTICS:
Unless otherwise stated, specifications hold for TA = 0°C to + 70°C for the
UC3835/6, –25°C to + 85°C for the UC2835/6, and –55°C to +125°C for the
UC1835/6, +V
IN = 6V, Driver Source= 0V, Driver Sink = 5V, TA = TJ.
UC 1835 − Typical configurations for a 2A,
Low Dropout 5V Regulator
UC1836 − Typical Configuration for a 2A,
Low Dropout Adjustable Regulator
Note 4: Suggested Pass devices are TIP 32B. (Dropout Voltage
≤
0.75V) or, D45H, (Dropout Voltage
≤
0.5V), or equivalents.
APPLICATION AND OPERATION INFORMATION
3