Datasheet

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
Reference Section
Output Voltage T
J=25°C 2.963 3.000 3.037 V
Overtemp 2.940 3.000 3.060 V
Line Regulation V
CC = 4.75V to 18V 10 mV
Load Regulation Io=0 to -5mA 10 mV
Oscillator Section
Free Running Freq T
J=25°C 576878kHz
Max Sync Frequency T
J=25°C 160 200 240 kHz
Charge Current V
CT = 1.5V 180 200 220 µA
Voltage Stability 2%
Temperature Stability 48%
Zero Detect Threshold 0.46 0.5 0.56 V
Error Amp 1 Section
Input Voltage V
O = 2V 1.445 1.475 1.505 V
Input Bias Current -0.4 -2 µA
Open Loop Gain V
O = 0.5 to 3V 65 90 dB
Output High V
EA(-) = 1.3V 3.1 3.5 3.9 V
Output Low V
EA(-) = 1.7V 0.1 0.2 V
Output Source Current V
EA(-) = 1.3V, Vo = 2V -350 -500 µA
Output Sink Current V
EA(-) = 1.7V, Vo = 2V 10 20 mA
Common Mode Range 0V
IN-1V V
Unity Gain Bandwidth T
J = 25°C (Note 4) 1 MHz
Maximum Source Impedance Note 5 100k Ω
UC1871
UC2871
UC3871
ELECTRICAL CHARACTERISTICS
Unless otherwise stated, these parameters apply for TA = -55°C to +125°C for the
UC1871; -25°C to +85°C for the UC2871; 0°C to +70°C for the UC3871; V
CC = 5V,
V
C = 15V, VENABLE = 5V, CT = 1nF, Zero Det = 1V.
ABSOLUTE MAXIMUM RATINGS
Analog Inputs . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 to +10V
V
CC, VC Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +20V
Zero Detect Input Current
High Impedance Source . . . . . . . . . . . . . . . . . . +10mA
Zero Detect
Low Impedance Source. . . . . . . . . . . . . . . . . . . . . +20V
Power Dissipation at T
A = 25°C . . . . . . . . . . . . . . . . . . . 1W
Storage Temperature . . . . . . . . . . . . . . . . -65°C to +150°C
Lead Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . 300°C
Note 1: Currents are positive into, negative out of the specified ter-
minal.
Note 2: Consult Packaging Section of Databook for thermal
limitations and considerations of package.
DIL-18, SOIC-18 (TOP VIEW)
J or N, DW Package
PACKAGE PIN FUNCTION
FUNCTION PIN
Gnd 1
B Out 2
A Out 3
VC 4
E/A 1 Comp 5
SS 6
E/A 1(-) 7
N/C 8
C
T 9
Zero Detect 10
N/C 11
VREF 12
E/A 2(+) 13
E/A 2(-) 14
E/A 2 Comp 15
V
CC 16
Enable 17
Flyback I
SENSE 18
D Out 19
C Out 20
PLCC-20 (Top View)
Q Package
CONNECTION DIAGRAMS
2