Datasheet

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SLUS579 − OCTOBER, 2003
4
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ELECTRICAL CHARACTERISTICS
T
A
= 0°C to 70°C for the UCC3819A, −40°C to 85°C for the UCC2819A, VCC = 12 V, R
T
= 22 kΩ, C
T
= 270 pF,
(unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
Over Voltage Protection and Enable
Over voltage reference
VREF
+0.48
VREF
+0.50
VREF
+0.52
V
Hysteresis 300 500 600 mV
Enable threshold 1.7 1.9 2.1
V
Enable hysteresis 0.1 0.2 0.3
V
Current Amplifier
Input offset voltage V
CM
= 0 V, V
CAOUT
= 3 V −3.5 0 2.5 mV
Input bias current V
CM
= 0 V, V
CAOUT
= 3 V −50 −100
nA
Input offset current V
CM
= 0 V, V
CAOUT
= 3 V 25 100
nA
Open loop gain V
CM
= 0 V, V
CAOUT
= 2 V to 5 V 90
dB
Common-mode rejection ratio V
CM
= 0 V to 1.5 V, V
CAOUT
= 3 V 60 80
dB
High-level output voltage I
L
= −120 µA 5.6 6.5 6.8
V
Low-level output voltage I
L
= 1 mA 0.1 0.2 0.5
V
Gain bandwidth product See Note 1 2.5 MHz
Voltage Reference
Input voltage, (UCC3819A) T
A
= 0°C to 70°C 7.387 7.5 7.613
V
Input voltage, (UCC2819A) T
A
= −40°C to 85°C 7.369 7.5 7.631
V
Load regulation I
REF
= 1 mA to 2 mA 0 10
mV
Line regulation VCC = 10.8 V to 15 V, See Note 2 0 10
mV
Short-circuit current V
REF
= 0 V −20 −25 −50 mA
Oscillator
Initial accuracy T
A
= 25°C 85 100 115 kHz
Voltage stability VCC = 10.8 V to 15 V −1% 1%
Total variation Line, temp, See Note 1 80 120 kHz
Ramp peak voltage 4.5 5 5.5
Ramp amplitude voltage
(peak to peak)
3.5 4 4.5
V
Peak Current Limit
PKLMT reference voltage −15 15 mV
PKLMT propagation delay 150 350 500 ns
NOTES: (1) Ensured by design, Not production tested.
(2) Reference variation for V
CC
< 10.8 V is shown in Figure 2.