TI UCC28C43-EP

UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
www.ti.com
FEATURES
•
•
•
•
•
•
•
(1)
Controlled Baseline
– One Assembly/Test Site, One Fabrication
Site
– Extended Temperature Performance of
–55°C to 125°C
Enhanced Diminishing Manufacturing Sources
(DMS) Support
Enhanced Product-Change Notification
Qualification Pedigree (1)
Enhanced Replacements for UC2842A Family
With Pin-to-Pin Compatibility
1 MHz Operation
50 µA Standby Current, 100 µA Maximum
Component qualification in accordance with JEDEC and
industry standards to ensure reliable operation over an
extended temperature range. This includes, but is not limited
to, Highly Accelerated Stress Test (HAST) or biased 85/85,
temperature cycle, autoclave or unbiased HAST,
electromigration, bond intermetallic life, and mold compound
life. Such qualification testing should not be viewed as
justifying use of this component beyond specified
performance and environmental limits.
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
•
•
•
•
•
•
•
•
Low Operating Current of 2.3 mA at 52 kHz
Fast 35 ns Cycle-by-Cycle Overcurrent
Limiting
±1 A Peak Output Current
Rail-to-Rail Output Swings With 25 ns Rise
and 20 ns Fall Times
±1% Initial Trimmed 2.5 V Error Amplifier
Reference
Trimmed Oscillator Discharge Current
New Undervoltage Lockout Versions
MSOP-8 Package Minimizes Board Space
APPLICATIONS
•
•
•
Switch Mode Power Supplies
DC-to-DC Converters
Board Mount Power Modules
DESCRIPTION
The UCC28C4x family are high performance current mode PWM controllers. They are enhanced BiCMOS
versions with pin-for-pin compatibility to the industry standard UC284xA family and UC284x family of PWM
controllers. In addition, lower startup voltage versions of 7 V are offered as UCC28C40 and UCC28C41.
Providing necessary features to control fixed frequency, peak current mode power supplies, this family offers
several performance advantages. These devices offer high frequency operation up to 1 MHz with low start up
and operating currents, thus minimizing start up loss and low operating power consumption for improved
efficiency. The devices also feature a fast current sense to output delay time of 35 ns, and a ±1 A peak output
current capability with improved rise and fall times for driving large external MOSFETs directly.
The UCC28C4x family is offered in 8-pin package SOIC (D).
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2006–2007, Texas Instruments Incorporated
UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
www.ti.com
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
AVAILABLE OPTIONS
TA
MAXIMUM
DUTY CYCLE
100%
–55°C to 125°C
50%
(1)
(2)
UVLO
ON/OFF
SOIC-8
SMALL OUTLINE
(D) (1)
14.5 V/9 V
UCC28C42MDREP (2)
8.4 V/7.6 V
UCC28C43MDREP
7 V/6.6 V
UCC28C40MDREP (2)
14.5 V/9 V
UCC28C44MDREP (2)
8.4 V/7.6 V
UCC28C45MDREP
7 V/6.6 V
UCC28C41MDREP (2)
D (SOIC-8) packages are available taped and reeled. Add R suffix to device type (e.g., UCC28C42DREP) to order quantities of 2500
devices per reel. Tube quantities are 75 for D packages (SOIC-8).
Product Preview
FUNCTIONAL BLOCK DIAGRAM
Note: Toggle flip-flop used only in UCC28C41, UCC28C44, and UCC28C45.
2
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UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
www.ti.com
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
Absolute Maximum Ratings
(1) (2)
over operating free-air temperature range (unless otherwise noted)
MIN
Supply voltage
MAX
20
V
Max ICC
30
mA
Output current, IOUT peak
±1
A
5
µJ
Output energy, capacitive load
Voltage rating
UNIT
VDD
COMP, CS, FB
–0.3
6.3
OUT
–0.3
20
RT/CT
–0.3
6.3
VREF
V
7
10
mA
TJ
Error amplifier output sink current
Operating junction temperature range (3)
–55
150
°C
Tstg
Storage temperature range
–65
150
°C
300
°C
Lead temperature (soldering, 10 s)
(1)
(2)
(3)
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating
conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
All voltages are with respect to ground. Currents are positive into and negative out of the specified terminals.
Long-term high temperature storage and/or extended use at maximum recommended operating conditions may result in a reduction of
overall device life. See http://www.ti.com/ep_quality for additional information about enhanced plastic packaging.
Dissipation Ratings
PACKAGE
D
θja
TA < 25°C
DERATING FACTOR
TA = 70°C
TA = 85°C
TA = 125°C
(°C/W)
POWER RATING
ABOVE TA = 25°C
POWER RATING
POWER RATING
POWER RATING
176
710 mW
5.68 mW/°C
454 mW
369 mW
142 mW
Recommended Operating Conditions
MIN
MAX
UNIT
VDD
Input voltage
18
V
VOUT
Output voltage range
18
V
IOUT
(1)
Average output current
200
mA
IOUT(ref) (1)
Reference output current
–20
mA
TJ (1)
Operating junction temperature
150
°C
(1)
–55
It is not recommended that the device operate under conditions beyond those specified in this table for extended periods of time.
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UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
www.ti.com
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
Electrical Characteristics
VDD = 15 V (1), RT = 10 kΩ, CT = 3.3 nF, CVDD = 0.1 µF and no load on the outputs, TA = TJ = –55°C to 125°C for the
UCC28C4x
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
5
5.1
V
0.2
20
mV
Reference
Output voltage, initial accuracy
TA = 25°C , IOUT = 1 mA
Line regulation
VDD = 12 V to 18 V
Load regulation
1 mA to 20 mA
Temperature stability
(2)
Total output variation
(2)
4.9
3
25
mV
0.2
0.4
mV/°C
5.18
V
4.82
Output noise voltage
10 Hz to 10 kHz, TA = 25°C
Long term stability
1000 hours, TA = 125°C (2)
µV
50
5
25
mV
–30
–45
–55
mA
TA = 25°C (3)
50.5
53
55
kHz
TA = Full Range (3)
50.5
57
KHz
Output short circuit
Oscillator
Initial accuracy
Voltage stability
VDD = 12 V to 18 V
(2)
Temperature stability
TMIN to TMAX
Amplitude
RT/CT pin peak to peak
Discharge current
0.2
2.85
%
1
2.5
%
1.9
V
TA = 25°C, RT/CT = 2 V (4)
7.7
8.4
9
mA
RT/CT = 2 V (4)
7.2
8.4
9.5
mA
2.475
2.500
2.525
2.45
2.50
2.55
V
–0.1
–2
µA
Error Amplifier
Feedback input voltage, initial accuracy
VCOMP = 2.5 V, TA = 25°C
Feedback input voltage, total variation
VCOMP = 2.5 V
Input bias current
AVOL
Open-loop voltage gain
VOUT = 2 V to 4 V
65
90
dB
1.5
MHz
2
14
mA
–0.5
–1
mA
5
6.8
Unity gain bandwidth
PSRR
Power-supply rejection ratio
VDD = 12 V to 18 V
Output sink current
VFB = 2.7 V, VCOMP = 1.1 V
Output source current
VFB = 2.3 V, VCOMP = 5 V
VOH
High-level output voltage
VFB = 2.3 V, RLOAD = 15 k to GND
VOL
Low-level output voltage
VFB = 2.7 V, RLOAD = 15 k to VREF
V
60
dB
V
0.1
1.1
V
3
3.15
V/V
3.15
V/V
Current Sense
Gain
PSRR
TA = 25°C
(5) (6)
TA = Full Range
2.85
(5) (6)
Maximum input signal
VFB < 2.4 V
Power-supply rejection ratio
VDD = 12 V to 18 V (2) (5)
2.825
Input bias current
CS to output delay
0.9
1
1.1
70
V
dB
–0.1
–2
µA
35
70
ns
COMP to CS offset
VCS = 0 V
1.15
V
VOUT low (RDS(on) pull-down)
ISINK = 200 mA
5.5
15
Ω
VOUT high (RDS(on) pull-up)
ISOURCE = 200 mA
10
25
Ω
Output
(1)
(2)
(3)
(4)
(5)
(6)
4
Adjust VDD above the start threshold before setting at 15 V.
Not production tested.
Output frequencies of the UCC28C41, UCC28C44, and UCC28C45 are one-half the oscillator frequency.
Oscillator discharge current is measured with RT = 10 kΩ to VREF.
Parameter measured at trip point of latch with VFB = 0 V.
DV
COM , 0 V v V
ACS +
CS v 900 mV
DVCS
Gain is defined as
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UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
www.ti.com
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
Electrical Characteristics (continued)
VDD = 15 V, RT = 10 kΩ, CT = 3.3 nF, CVDD = 0.1 µF and no load on the outputs, TA = TJ = –55°C to 125°C for the UCC28C4x
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Rise tIme
TA = 25°C, CLOAD = 1 nF
25
50
ns
Fall time
TA = 25°C, CLOAD = 1 nF
20
40
ns
15.5
Undervoltage Lockout (UVLO)
Start threshold
Minimum operating voltage
UCC28C42-EP, UCC28C44-EP
13.5
14.5
UCC28C43-EP, UCC28C45-EP
7.8
8.4
9
UCC28C40-EP, UCC28C41-EP
6.5
7
7.5
UCC28C42-EP, UCC28C44-EP
8
9
10
UCC28C43-EP, UCC28C45-EP
7
7.6
8.2
UCC28C40-EP, UCC28C41-EP
6.1
6.6
7.1
UCC28C42-EP, UCC28C43-EP,
UCC28C40-EP, UCC28C44-EP,
UCC28C45-EP, UCC28C41-EP
94
96
47
48
V
V
PWM
Maximum duty cycle
Minimum duty cycle
%
0%
Current Supply
ISTART-UP Start-up current
VDD = UVLO start threshold (–0.5 V)
50
100
µA
IDD
VFB = VCS = 0 V
2.3
3
mA
Operating supply current
PDIP (P) or SOIC (D) PACKAGE
(TOP VIEW)
COMP
FB
CS
RT/CT
1
8
2
7
3
6
4
5
VREF
VDD
OUT
GND
Pin Assignments
COMP: This pin provides the output of the error amplifier for compensation. In addition, the COMP pin is
frequently used as a control port by utilizing a secondary-side error amplifier to send an error signal across the
secondary-primary isolation boundary through an opto-isolator.
CS: The current-sense pin is the noninverting input to the PWM comparator. This is compared to a signal
proportional to the error amplifier output voltage. A voltage ramp can be applied to this pin to run the device with
a voltage mode control configuration.
FB: This pin is the inverting input to the error amplifier. The noninverting input to the error amplifier is internally
trimmed to 2.5 V ± 1%.
GND: Ground return pin for the output driver stage and the logic-level controller section.
OUT: The output of the on-chip drive stage. OUT is intended to directly drive a MOSFET. The OUT pin in the
UCC28C40, UCC28C42, and UCC28C43 is the same frequency as the oscillator, and can operate near 100%
duty cycle. In the UCC28C41, UCC28C44, and the UCC28C45, the frequency of OUT is one-half that of the
oscillator due to an internal T flipflop. This limits the maximum duty cycle to <50%.
RT/CT: Timing resistor and timing capacitor. The timing capacitor should be connected to the device ground
using minimal trace length.
VDD: Power supply pin for the device. This pin should be bypassed with a 0.1 µF capacitor with minimal trace
lengths. Additional capacitance may be needed to provide hold up power to the device during startup.
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BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
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SGLS352B – DECEMBER 2006 – REVISED MAY 2007
VREF: 5-V reference. For stability, the reference should be bypassed with a 0.1 µF capacitor to ground using
the minimal trace length possible.
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UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION
This device is a pin-for-pin replacement of the bipolar UC2842 family of controllers—the industry standard PWM
controller for single-ended converters. Familiarity with this controller family is assumed.
The UCC28C4x series is an enhanced replacement with pin-to-pin compatibility to the bipolar UC284x and
UC284xA families. The new series offers improved performance when compared to older bipolar devices and
other competitive BiCMOS devices with similar functionality. Note that these improvements discussed below
generally consist of tighter specification limits that are a subset of the older product ratings, maintaining drop-in
capability. In new designs these improvements can be utilized to reduce the component count or enhance circuit
performance when compared to the previously available devices.
Advantages
This device increases the total circuit efficiency whether operating off-line or in dc input circuits. In off-line
applications the low start-up current of this device reduces steady state power dissipation in the startup resistor,
and the low operating current maximizes efficiency while running. The low running current also provides an
efficiency boost in battery-operated supplies.
Low-Voltage Operation
Two members of the UCC28C4x family are intended for applications that require a lower start-up voltage than
the original family members. The UCC28C40 and UCC28C41 have a turn-on voltage of 7 V typical and exhibit
hysteresis of 0.4 V for a turn-off voltage of 6.6 V. This reduced start-up voltage enables use in systems with
lower voltages, such as 12 V battery systems that are nearly discharged.
High-Speed Operation
The BiCMOS design allows operation at high frequencies that were not feasible in the predecessor bipolar
devices. First, the output stage has been redesigned to drive the external power switch in approximately
one-half the time of the earlier devices. Second, the internal oscillator is more robust, with less variation as
frequency increases. In addition, the current sense to output delay has been reduced by a factor of three, to 45
ns typical. These features combine to provide a device capable of reliable high-frequency operation.
The UCC28C4x family oscillator is true to the curves of the original bipolar devices at lower frequencies, yet
extends the frequency programmability range to at least 1 MHz. This allows the device to offer pin-to-pin
capability where required, yet capable of extending the operational range to the higher frequencies typical of
latest applications. When the original UC2842 was released in 1984, most switching supplies operated between
20 kHz and 100 kHz. Today, the UCC28C4x can be used in designs cover a span roughly ten times higher than
those numbers.
Start/Run Current Improvements
The start-up current is only 60 µA typical, a significant reduction from the bipolar device's ratings of 300 µA
(UC284xA). For operation over the temperature range of –55°C to 125°C, the UCC28C4x devices offer a
maximum startup current of 100 µA, an improvement over competitive BiCMOS devices. This allows the
power-supply designer to further optimize the selection of the start-up resistor value to provide a more efficient
design. In applications where low component cost overrides maximum efficiency the low run current of 2.3 mA
typical may allow the control device to run directly through the single resistor to (+) rail, rather than needing a
bootstrap winding on the power transformer, along with a rectifier. The start/run resistor for this case must also
pass enough current to allow driving the primary switching MOSFET, which may be a few milliamps in small
devices.
±1% Initial Reference Voltage
The BiCMOS internal reference of 2.5 V has an enhanced design and utilizes production trim to allow initial
accuracy of ±1% at room temperature and ±2% over the full temperature range. This can be used to eliminate
an external reference in applications that do not require the extreme accuracy afforded by the additional device.
This is very useful for nonisolated dc-to-dc applications where the control device is referenced to the same
common as the output. It is also applicable in offline designs that regulate on the primary side of the isolation
boundary by looking at a primary bias winding, or perhaps from a winding on the output inductor of a
buck-derived circuit.
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BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
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SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION (continued)
Reduced Discharge Current Variation
The original UC2842 oscillator did not have trimmed discharged current, and the parameter was not specified on
the data sheet. Since many customers attempted to use the discharge current to set a crude dead-time limit, the
UC2842A family was released with a trimmed discharge current specified at 25°C. The UCC28C4x series now
offers even tighter control of this parameter, with approximately ±3% accuracy at 25°C, and less than 10%
variation over temperature using the UCC28C4x devices. This level of accuracy can enable a meaningful limit to
be programmed, a feature not currently seen in competitive BiCMOS devices. The improved oscillator and
reference also contribute to decreased variation in the peak-to-peak variation in the oscillator waveform, which is
often used as the basis for slope compensation for the complete power system.
Soft-Start
Figure 1 provides a typical soft-start circuit for use with the UCC28C42. The values of R and C should be
selected to bring the COMP pin up at a controlled rate, limiting the peak current supplied by the power stage.
After the soft-start interval is complete, the capacitor continues to charge to VREF, effectively removing the PNP
transistor from circuit considerations.
The optional diode in parallel with the resistor forces a soft-start each time the PWM goes through UVLO and
the reference (VREF) goes low. Without the diode, the capacitor otherwise remains charged during a brief loss of
supply or brownout, and no soft-start is enabled upon reapplication of VIN.
VREF
8
COMP
1
UCC28C42
GND
5
UDG-01072
Figure 1.
Oscillator Synchronization
The UCC28C4x oscillator has the same synchronization characteristics as the original bipolar devices. Thus, the
information in the application report U-100A, UC2842/3/4/5 Provides Low-Cost Current-Mode Control (SLUA143)
still applies. The application report describes how a small resistor from the timing capacitor to ground can offer
an insertion point for synchronization to an external clock (see Figure 2 and Figure 3). Figure 2 shows how the
UCC28C42 can be synchronized to an external clock source. This allows precise control of frequency and dead
time with a digital pulse train.
8
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BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
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SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION (continued)
8
VREF
4
RT / CT
RT
SYNCHRONIZATION
CIRCUIT INPUT
CT
UCC28C42
PWM
24
UDG-01069
Figure 2. Oscillator Synchronization Circuit
CLOCK
INPUT
PWM
OUT
UPPER THRESHOLD
LOW
HIGH
LOW
LOWER THRESHOLD
ON .
OFF .
ON .
VCT (ANALOG)
OUTPUT A
UPPER THRESHOLD
VCT
VSYNC (DIGITAL)
LOWER THRESHOLD
COMBINED
UDG−01070
Figure 3. Synchronization to an External Clock
Precautions
The absolute maximum supply voltage is 20 V, including any transients that may be present. If this voltage is
exceeded, device damage is likely. This is in contrast to the predecessor bipolar devices that could survive up to
30 V. Thus, the supply pin should be decoupled as close to the ground pin as possible. Also, since no clamp is
included in the device, the supply pin should be protected from external sources that could exceed the 20 V
level.
Careful layout of the printed board has always been a necessity for high-frequency power supplies. As the
device switching speeds and operating frequencies increase, the layout of the converter becomes increasingly
important.
This 8-pin device has only a single ground for the logic and power connections. This forces the gate drive
current pulses to flow through the same ground that the control circuit uses for reference. Thus, the interconnect
inductance should be minimized as much as possible. One implication is to place the device (gate driver)
circuitry close to the MOSFET it is driving. Note that this can conflict with the need for the error amplifier and the
feedback path to be away from the noise generating components.
Circuit Applications
Figure 4 shows a typical off-line application.
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BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
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SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION (continued)
D50
F1
12 V
OUT
T1
R10
C52
C3
C12
+
AC INPUT
100 Vac - 240 Vac
EMI FILTER
REQUIRED
C55
R56
BR1
L50
D2
R11
C1A
D51
C18
5V
OUT
R12
RT1
C53
C54
D6
R55
C5
SEC
COMMON
R6
R50
UCC28C44
IC2
1
COMP
REF
R16
8
Q1
2
FB
VCC
7
3
CS
OUT
6
4
RT/CT
GND 5
IC2
C50
C13
R50
R53
R52
C51
K
IC3
A
R
R54
UDG-01071
Figure 4. Typical Off-Line Application
Figure 5 shows the forward converter with synchronous rectification. This application provides 48 V to 3.3 V at
10 A with over 85% efficiency, and uses the UCC28C42 as the secondary-side controller and UCC3961 as the
primary-side startup control device.
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46.4k
C5
0.1uF
7
6
5
4
3
2
AGnd
Ref
Rt
FB
SS
SD
OVS
R12
200
ucc3961
U1
R2
2
1
C7
8
9
10
11
12
13
14
T2
4
3
R4
1.5k
300
R13
C8
1uF
Q2
470pF
C6
76.8k
R5
R6
4.7
C10
2.7nF
0.1uF
C9
R8
R10
1k
5.1k
D1
R14
50k
R15
20k 40%
0.33
R9
Q1
C22
4.7nF
D3
20k
R24
20k
402
R25
20k
R26
R28
R19
20
4.7
680pF
100
3300pF
C12
5.6nF
C16
21.5k
C23
R17
R16
BAR74
R23
D5
BAR74
Q3
C17
4700pF
1500pF
C11
4
3
2
1
4
3
2
1
Vcc
DT
Rt/Ct
CS
FB
U2
LODR
BTLO
HIDR
7.5k
R18
UCC28C4x
PGND
5
6
7
8
C19
470uF
4700pF
U4
TPS2832
BOOT
IN
COMP
R27
4.7
10
R21
Q4
GND
OUT
Vcc
REF
5
6
7
8
2uF
C26
470uF
C20
0.22uF
C13
C14
1uF
C24
0.1uF
D6
BZX84C15LT1
PWRGND
0.1uF
C21
3r3V
R22
100
C15
1uF
+
100pF
Vs
CS
PGnd
Out
Vdd
St
UVS
2.4k
R3
1.2k
C25
0.047uF
R20
10
C18
+
R11
10nF
1
+
0.22uF
C3
470uF
C1
R1
32.4k
10k
D2
T1
+
VinN
VinP
R7
C2
1nF
L1
4.7uH
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UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION (continued)
Figure 5. Forward Converter With Synchronous Rectification
Using the UCC28C42 as the Secondary-Side Controller
11
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BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
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SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION (continued)
OSCILLATOR DISCHARGE CURRENT
vs
TEMPERATURE
OSCILLATOR FREQUENCY
vs
TIMING RESISTANCE AND CAPACITANCE
9.5
10 M
IDISCH − Oscillator Discharge Current − mA
CT = 220 pF
CT = 470 pF
f − Frequency − Hz
1M
CT = 1 nF
100 k
10 k
CT = 4.7 nF
CT = 2.2 nF
9.0
8.5
8.0
7.5
7.0
1k
1k
10 k
100 k
−50
−25
0
RT − Timing Resistance − W
Figure 6.
200
90
180
1.4
120
50
100
40
80
30
PHASE
MARGIN
10
0
1M
1.2
COMP to CS
60
Phase Margin − (°)
Gain − (dB)
70
140
1 k 10 k 100 k
f − Frequency − Hz
1.0
0.8
60
0.6
40
0.4
20
0.2
0
10 M
0.0
−50
−25
0
25
50
TJ − Temperature − °C
Figure 8.
12
125
1.6
GAIN
100
100
1.8
160
80
10
75
COMP to CS OFFSET VOLTAGE (with CS = 0)
vs
TEMPERATURE
100
1
50
Figure 7.
ERROR AMPLIFIER
FREQUENCY RESPONSE
20
25
TJ − Temperature − °C
Figure 9.
Submit Documentation Feedback
75
100
125
UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
www.ti.com
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION (continued)
REFERENCE VOLTAGE
vs
TEMPERATURE
ERROR AMPLIFIER REFERENCE VOLTAGE
vs
TEMPERATURE
2.55
VEAREF − Error Amplifier Reference Voltage − V
5.05
VREF − Reference Voltage − V
5.04
5.03
5.02
5.01
5.00
4.99
4.98
4.97
4.96
4.95
−50
2.54
2.53
2.52
2.51
2.50
2.49
2.48
2.47
2.46
2.45
−25
0
25
50
75
100
125
−50
−25
TJ − Temperature − °C
50
75
100
Figure 10.
Figure 11.
REFERENCE SHORT-CIRCUIT CURRENT
vs
TEMPERATURE
ERROR AMPLIFIER INPUT BIAS CURRENT
vs
TEMPERATURE
125
200
−37
IBIAS − Error Amplifier Input Bias Current − nA
ISC − Reference Short Circuit Current − mA
25
TJ − Temperature − °C
−35
−39
−41
−43
−45
−47
−49
−51
−53
−55
−50
0
150
100
50
0
−50
−100
−150
−200
−25
0
25
50
75
TJ − Temperature − °C
100
125
−50
Figure 12.
−25
0
25
50
75
TJ − Temperature − °C
100
125
Figure 13.
Submit Documentation Feedback
13
UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
www.ti.com
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION (continued)
UNDERVOLTAGE LOCKOUT
vs
TEMPERATURE (UCC28C45)
UNDERVOLTAGE LOCKOUT
vs
TEMPERATURE (UCC28C44)
16
9.0
15
13
VUVLO − UVLO Voltage − V
VUVLO − UVLO Voltage − V
14
UVLO
ON
12
UVLO
OFF
11
10
9
8.6
8.4
8.2
8.0
7.8
7.6
8
7.4
7
7.2
6
−50
UVLO
ON
8.8
−25
0
25
50
75
100
UVLO
OFF
7.0
−50
125
TJ − Temperature − °C
−25
0
Figure 14.
100
125
Figure 15.
UNDERVOLTAGE LOCKOUT
vs
TEMPERATURE (UCC28C41)
SUPPLY CURRENT
vs
OSCILLATOR FREQUENCY
25
7.3
7.2
IDD − Supply Current − mA
UVLO
ON
7.1
VUVLO − UVLO Voltage − V
25
50
75
TJ − Temperature − °C
7.0
6.9
6.8
6.7
1-nF LOAD
20
15
10
NO LOAD
6.6
5
6.5
UVLO
OFF
6.4
6.3
−50
0
0k
−25
0
25
50
75
100
125
200 k
400 k
600 k
f − Frequency − Hz
TJ − Temperature − °C
Figure 16.
14
Figure 17.
Submit Documentation Feedback
800 k
1M
UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
www.ti.com
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION (continued)
SUPPLY CURRENT
vs
TEMPERATURE
40
3.0
OUTPUT RISE TIME AND FALL TIME
vs
TEMPERATURE
10% to 90%
VDD = 12 V
2.9
Output Rise and Fall TIme − ns
35
IDD − Supply Current − mA
2.8
2.7
2.6
2.5
2.4
NO LOAD
2.3
2.2
tr
(1 nF)
30
tf
(1 nF)
25
20
15
2.1
2.0
−50
−25
0
25
50
75
100
10
−50
125
−25
0
25
TJ − Temperature − °C
Figure 18.
100
125
100
125
MAXIMUM DUTY CYCLE
vs
TEMPERATURE
100
100
UCC28C40
UCC28C42
UCC28C43
CT = 220 pF
98
Maximum Duty Cycle − %
90
Duty Cycle − %
75
Figure 19.
MAXIMUM DUTY CYCLE
vs
OSCILLATOR FREQUENCY
80
70
CT = 1 nF
96
94
92
60
50
50
TJ − Temperature − °C
0
500
1000
1500
2000
2500
90
−50
−25
0
25
50
75
TJ − Temperature − °C
f − Frequency − kHz
Figure 20.
Figure 21.
Submit Documentation Feedback
15
UCC28C4x-EP
BiCMOS LOW-POWER CURRENT-MODE PWM CONTROLLERS
www.ti.com
SGLS352B – DECEMBER 2006 – REVISED MAY 2007
APPLICATION INFORMATION (continued)
MAXIMUM DUTY CYCLE
vs
TEMPERATURE
1.10
UCC28C41
UCC28C44
UCC28C45
VCS_th − Current Sense Threshold − V
Output Rise and Fall TIme − ns
50
49
48
47
46
45
−50
CURRENT-SENSE THRESHOLD VOLTAGE
vs
TEMPERATURE
1.05
1.00
0.95
0.90
−25
0
25
50
75
100
−50
125
−25
0
25
Figure 22.
Figure 23.
CS TO OUT DELAY TIME
vs
TEMPERATURE
70
tD − CS to OUT Delay Time − ns
65
60
55
50
45
40
35
30
−50
75
TJ − Temperature − °C
TJ − Temperature − °C
−25
0
25
50
75
TJ − Temperature − °C
Figure 24.
16
50
Submit Documentation Feedback
100
125
100
125
PACKAGE OPTION ADDENDUM
www.ti.com
9-Oct-2010
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package
Drawing
Pins
Package Qty
Eco Plan
(2)
Lead/
Ball Finish
MSL Peak Temp
(3)
Samples
(Requires Login)
UCC28C43MDREP
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU NIPDAU Level-1-260C-UNLIM
Contact TI Distributor
or Sales Office
UCC28C45MDREP
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU NIPDAU Level-1-260C-UNLIM
Contact TI Distributor
or Sales Office
V62/07615-01XE
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU NIPDAU Level-1-260C-UNLIM
Contact TI Distributor
or Sales Office
V62/07615-02XE
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU NIPDAU Level-1-260C-UNLIM
Contact TI Distributor
or Sales Office
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
OTHER QUALIFIED VERSIONS OF UCC28C43-EP, UCC28C45-EP :
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
9-Oct-2010
• Catalog: UCC28C43, UCC28C45
NOTE: Qualified Version Definitions:
• Catalog - TI's standard catalog product
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Jul-2012
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
UCC28C43MDREP
SOIC
D
8
2500
330.0
12.4
6.4
5.2
2.1
8.0
12.0
Q1
UCC28C45MDREP
SOIC
D
8
2500
330.0
12.4
6.4
5.2
2.1
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Jul-2012
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
UCC28C43MDREP
SOIC
D
8
2500
367.0
367.0
35.0
UCC28C45MDREP
SOIC
D
8
2500
367.0
367.0
35.0
Pack Materials-Page 2
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