UC1854
UC2854
UC3854
ABSOLUTE MAXIMUM RATINGS
Supply Voltage VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35V
GT Drv Current, Continuous . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5A
GT Drv Current, 50% Duty Cycle. . . . . . . . . . . . . . . . . . . . . . . . . 1.5A
Input Voltage, VSENSE, VRMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11V
Input Voltage, ISENSE, Mult Out . . . . . . . . . . . . . . . . . . . . . . . . . . . 11V
Input Voltage, PKLMT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5V
Input Current, RSET, IAC, PKLMT, ENA . . . . . . . . . . . . . . . . . . . 10mA
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1W
Storage Temperature . . . . . . . . . . . . . . . . . . . . –65oC to +150oC
Lead Temperature (Soldering, 10 Seconds) . . . . . . . . . . . . . . +300oC
Note 1: All voltages with respect to Gnd (Pin 1).
Note 2: All currents are positive into the specified termi-
nal.
Note 3: ENA input is internally clamped to approximately
14V.
Note 4: Consult Unitrode Integrated Circuits databook for
information regarding thermal specifications and limita-
CONNECTION DIAGRAMS
PACKAGE PIN FUNCTION
DIL–16 & SOIC-16
(Top View)
J, N & DW Packages
PLCC-20 & LCC-20
(Top View)
Q & L Packages
FUNCTION
N/C
PIN
1
Gnd
2
PKLMT
CA Out
ISENSE
N/C
Mult Out
IAC
VA Out
VRMS
N/C
VREF
ENA
VSENSE
RSET
N/C
SS
CT
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
VCC
GT Drv
Unless otherwise stated, VCC=18V, RSET=15k to ground, CT=1.5nF to ground, PKLMT=1V, ENA=7.5V,
VRMS=1.5V, IAC=100µA, ISENSE=0V, CA Out=3.5V, VA Out=5V, VSENSE=7.5V, no load on SS, CA Out,
VA Out, REF, GT Drv, –55oC<TA<125oC for the UC1854, –40oC<TA<85oC for the UC2854, and
0oC<TA<70oC for the UC3854, and TA=TJ.
ELECTRICAL
CHARACTERISTICS
PARAMETER
OVERALL
TEST CONDITIONS
MIN
TYP
MAX
UNITS
Supply Current, Off
ENA=0V
1.5
10
2.0
16
mA
mA
V
Supply Current, On
VCC Turn-On Threshold
VCC Turn-Off Threshold
ENA Threshold, Rising
ENA Threshold Hysteresis
ENA Input Current
14.5
9
16
17.5
11
10
V
2.4
2.55
0.25
–0.2
–.01
2.7
0.3
5.0
1.0
V
0.2
V
ENA=0V
VRMS=5V
–5.0
–1.0
µA
µA
VRMS Input Current
VOLTAGE AMPLIFIER
Voltage Amp Offset Voltage
VSENSE Bias Current
Voltage Amp Gain
VA Out=5V
–8
–500
70
8
mV
nA
dB
V
–25
100
500
Voltage Amp Output Swing
0.5 to 5.8
–20
Voltage Amp Short Circuit Current VA Out=0V
SS Current SS=2.5V
–36
–20
–5
–6
mA
µA
–14
2