Datasheet

UNISONIC TECHNOLOGIES CO., LTD
UC3854
Preliminary
CMOS IC
ENHANCED HIGH POWER
FACTOR PREREGULATOR

DESCRIPTION
The UTC UC3854 provide all the functions necessary for active
power factor corrected preregulators. The controller achieves near
unity power factor by shaping the AC input line current waveform to
correspond to that of AC input line voltage. Average current mode
control maintains stable, low distortion sinusoidal line current
without the need for slope compensation, unlike peak current mode
control.
Designed in UTC’s Bipolar process, the UTC UC3854 offers
new features such as wide bandwidth, low offset Current Amplifier,
a faster responding and improved accuracy enable comparator, a
VREF "good" comparator, UVLO threshold options (16/10V for
offline, 10.5/10V for startup from an auxiliary 12V regulator), lower
startup supply current, and an enhanced multiply/divide circuit.
New features like the improved amplifier current sinking capability,
amplifier output clamps, and low offset VAC pin reduce the external
component count while improving performance. Improved common
mode input range of the Multiplier output/Current Amp input allow
the designer greater flexibility in choosing a method for current
sensing. Unlike its predecessor, the maximum multiplier output
current is now clamped to a maximum of 2 * IAC at all times.
A 1% 7.5V reference, fixed frequency oscillator, PWM, Voltage
Amplifier with softstart, line voltage feedforward (VRMS squarer),
input supply voltage clamp, and over current comparator round out
the list of features.

SOP-16
FEATURES
* Controls Boost Preregulator to Near Unity Power Factor
* Limits Line Distortion
* World-Wide Line Operation
* Accurate Power Limiting
* Fixed Frequency Average Current Mode Control
* High Bandwidth (5MHz), Low Offset Current Amplifier
* Integrated Current and Voltage Amp Output Clamps
* Multiplier Improvements: Linearity, 500mV VAC Offset (eliminates
external resistor), 0-5V Multout Common Mode Range
* VREF "GOOD" Comparator
* Faster and Improved Accuracy ENABLE Comparator
* 300uA Startup Supply Current
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Copyright © 2015 Unisonic Technologies Co., Ltd
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
Preliminary
CMOS IC
ORDERING INFORMATION
Ordering Number
UC3854xG-S16-R
Package
SOP-16
Packing
Tape Reel
UC3854xG-S16-R

(1) Packing Type
(1) R: Tape Reel
(2) Package Type
(2) S16: SOP-16
(3) Green Package
(3) G: Halogen Free and Lead Free
(4) VCC Turn-On/Off
(4) refer to ELECTRICAL CHARACTERISTICS
MARKING
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Preliminary

PIN CONFIGURATION

PIN DESCRIPTION
PIN NO.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16

PIN NAME
GND
PKLMT
CA OUT
ISNESE
Mult OUT
IAC
VA OUT
VRMS
VREF
ENA
VSNESE
RSET
SS
CT
VCC
GT Drv
CMOS IC
DESCRIPTION
Ground. All voltage are measured with respect to GND .
Peak Limit. The threshold for PKLMT is 0V.
Current Error Amplifier Output.
Current Sense Minus. The negative input to the current amplifier.
Multiplier/Divider Output. Multiplier output and non-inverting input connected together
Analog Input AC Current.
Voltage Error Amplifier Output.
RMS Line Voltage.
Voltage Reference Output.
Enable. A logic input, set “H” active.
Voltage Error Amplifier Inverting Input.
Oscillator Charging Current.
Soft Start.
Oscillator Timing Capacitor.
Positive supply voltage.
Gate Driver.
BLOCK DIAGRAM
VA
OUT
7
VCC
Mult
CA PK
OUT OUT LMT
5
3
2
RFE
9
7.5V
REF
(A) 16V/10V
(B) 10.5V/10V
ENA 10
7.2V
2.65V/2.15V
3V
A
IM=
C
IAC 6
VRMS 8
SS 13
15 VCC
A
VSENSE 11
X2
S
14µA
16 GT Drv
Q
20V
OSCILLATOR
1 GND
4
ISNESE
UNISONIC TECHNOLOGIES CO., LTD
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R
R
B
C
14
CT
12
RSET
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
Preliminary
CMOS IC
ABSOLUTE MAXIMUM RATING
PARAMETER
RATINGS
UNIT
22
V
Continuous
0.5
A
GT Drv Current
IOUT
50% Duty Cycle
1.5
A
VSENSE, VRMS
11
V
ISENSE, Mult Out
11
V
Input Voltage
VIN
PKLMT
5
V
RSET, IAC PKLMT, ENA
10
mA
Power Dissipation
PD
1
W
Storage Temperature
TSTG
-65~+150
°C
Notes: 1. Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
2. All voltages with respect to Gnd (Pin 1)
3. All currents are positive into the specified terminal
Supply Voltage

SYMBOL
VCC
ELECTRICAL CHARACTERISTICS
Unless otherwise stated, VCC=18V, RT=8.2k, CT=1.5nF, PKLMT=1V, VRMS=1.5V, IAC=100uA, I=0V, CA Out=3.5V, VA
Out=5V, VSENSE=3V, 0°C <TA<70°C, TA=TJ.
PARAMETER
SYMBOL TEST CONDITIONS
MIN
TYP MAX UNIT
Overall
Supply Current, Off
ICC(On) CAO, VAO = 0V, VCC= UVLO - 0.3V
250
400
uA
Supply Current, On
ICC(Off)
12
18
mA
UC3854A
16
17.5
V
VCC Turn-On Threshold
VCC(On)
UC3854B
10.5 11.2
V
VCC Turn-OFF Threshold
VCC(Off) UC3854A/B
9
10
V
VCC Clamp
VCC(Clamp) I(VCC) = ICC(on) + 5mA
18
20
22
V
Voltage Amplifier
Input Voltage
VSENSE
2.9
3.0
3.1
V
VSENSE Bias Current
IVSENSE
-500
-25
500
nA
Open Loop Gain
AVA
VOUT= 2 ~ 5V
70
100
dB
VOUT High
VHV
ILOAD= -500uA
6
V
VOUT Low
VLV
ILOAD= 500uA
0.3
0.5
V
Output Short Circuit Current
ISCV
VOUT= 0V
1.5
3.5
mA
Gain Bandwidth Product
GBV
Fin = 100kHz, 10mV p-p, (Note 1)
1
mHz
Current amplifier
-4
TA=+25°C
0
mV
Input Offset Voltage
IOFFC
VCM= 0V
-5.5
Overtemp
0
mV
Input Bias Current(sense)
ICSENSE VCM= 0V
-500
500
nA
Open Loop Gain
ACA
VCM= 0V, VOUT= 2 ~ 6V
80
110
dB
VOUT High
VHC
ILOAD= -500uA
8
V
VOUT Low
VLC
ILOAD= 500uA
0.3
0.5
V
Output Short Circuit Current
ISCC
VOUT= 0V
1.5
3.5
mA
Common Mode Range
VCMC
-0.3
5
V
Gain Bandwidth Product
GBC
Fin = 100kHz, 10mV p-p, (Note 1)
3
5
mHz
Reference
IREF = 0mA, TA= 25°C
7.4
7.5
7.6
V
Output Voltage
VREF
IREF= 0mA
7.35
7.5
7.65
V
△VLOAD IREF= 1 ~ 10mA
Load Regulation
0
8
20
mV
△VLINE VCC=12 ~ 18V
Line Regulation
0
14
25
mV
Short Circuit Current
ISCR
VREF= 0V
25
35
60
mA
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
Preliminary
CMOS IC
ELECTRICAL CHARACTERISTICS (Cont.)
PARAMETER
SYMBOL
Oscillator
Initial Accuracy
f0
△f
Voltage Stability
VCC
Total Variation
fT
Ramp Amplitude (p-p)
VPP
Ramp Valley Voltage
VVAL
Enable/Softstart /Current Limit
Enable Threshold
VENA
Enable Hysteresis
VHYS
Enable Input Bias Current
IENA
Propagation Delay to Disable
TENA
SS Charge Current
ISS
PKLMT Offset Voltage
VOFFP
PKLMT Input Current
IPK
PKLMT Propagation Delay
TPK
Multiplier
Output Current - IAC Limited
ILIM
Output Current - Zero
IZERO
Output Current - Power Limited
IPLIM
Output Current
Gain Constant
Gate Driver
Output High Voltage
IMULT
K
TEST CONDITIONS
TA= 25°C
VCC=12 ~ 18V
Line, Temp
TYP
MAX
UNIT
85
100
1
115
kHz
%
kHz
V
V
80
4.9
0.8
2.35
VFAULT= 2.5V
VENABLE= 0V
Enable Overdrive= -100mV (Note 1)
VSOFTSTART= 2.5V
VPKLMT= -0.1V
(Note 1)
IAC=100mA, VRMS= 1V, RSET= 10k
IAC=0uA, RSET= 10k
VRMS= 1.5V, Va = 6V
VRMS= 1.5V, Va= 2V
VRMS= 1.5V, Va= 5V
VRMS= 5V, Va= 2V
VRMS= 5V, Va= 5V
(Note 2) VRMS= 1.5V, TJ= 25°C, Va = 6V
VHG
IOUT= -200mA, VCC=15V
IOUT= 200mA
Output Low Voltage Output
VLG
IOUT= 10mA
Low (UVLO)
IOUT= 50mA, VCC=0V
Output Rise / Fall Time
TRF
CLOAD= 1nF (Note 1)
Output Peak Current
IPEAK
CLOAD= 10nF (Note 1)
Notes: 1. Guaranteed by design, not 100% tested in production
I *(Va  1.5V)
2. Gain constant (K)= AC
2
VRMS * IMO
UNISONIC TECHNOLOGIES CO., LTD
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MIN
10
-15
-200
-220
-2.0
-230
-1.1
12
120
5.9
1.3
2.55
500
-2
300
14
2.8
600
-5
24
15
-100
150
-200
-0.2
-200
-22
-156
-2
-14
-1.0
12.8
1
300
0.9
35
1.0
-170
2.0
-170
-0.9
2.2
500
1.5
V
mV
uA
ns
mV
uA
ns
uA
uA
uA
uA
uA
uA
uA
A/A
v
V
mV
V
ns
A
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Preliminary
CMOS IC
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
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www.unisonic.com.tw
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