Document Outline
- features
- description
- block diagram
- absolute maximum ratings over operating free-air temperature range (unl\
ess otherwise noted)
- electrical characteristics, T A = 40 C to 125 C, V CC = 10 V (see \
Note 1), R T = 100 k from REF to
RC, C T = 330 pF fro
- electrical characteristics, T A = 40 C to 125 C, V CC = 10 V (see \
Note 1), R T = 100 k from REF to
RC, C T = 330 pF fro
- electrical characteristics, T A = 40 C to 125 C, V CC = 10 V (see \
Note 1), R T = 100 k from REF to
RC, C T = 330 pF fro
- detailed terminal descriptions
- COMP
- CS
- FB
- ground (GND)
- OUT
- RC
- voltage reference (REF)
- power (V CC)
- PARAMETER MEASUREMENT INFORMATION
- MECHANICAL DATA
- D (R-PDSO-G**) PLASTIC SMALL-OUTLINE PACKAGE
- IMPORTANT NOTICE
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
D
Controlled Baseline
One Assembly/Test Site, One Fabrication
Site
D
Extended Temperature Performance of
40
C to 125
C
D
Enhanced Diminishing Manufacturing
Sources (DMS) Support
D
Enhanced Product Change Notification
D
Qualification Pedigree
D
ESD Protection Exceeds 200 V Using
Machine Model (C = 200 pF, R = 0)
D
100
A Typical Starting Supply Current
D
500
A Typical Operating Supply Current
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.
D
Operation to 1MHz
D
Internal Soft Start
D
Internal Fault Soft Start
D
Internal Leading-Edge Blanking of the
Current Sense Signal
D
1 Amp Totem-Pole Output
D
70 ns Typical Response from
Current-Sense to Gate Drive Output
D
1.5% Tolerance Voltage Reference
D
Same Pinout as UC3842 and UC3842A
description
The UCC2800/1/2/3/4/5 family of high-speed, low-power integrated circuits contain all of the control and drive
components required for off-line and DC-to-DC fixed frequency current-mode switching power supplies with
minimal parts count.
These devices have the same pin configuration as the UC2842/3/4/5 family, and also offer the added features
of internal full-cycle soft start and internal leading-edge blanking of the current-sense input.
The UCC2800/1/2/3/4/5 family offers choice of maximum duty cycle and critical voltage levels. Lower reference
parts such as the UCC2803 and UCC2805 fit best into battery operated systems, while the higher reference
and the higher UVLO hysteresis of the UCC2802 and UCC2804 make these ideal choices for use in off-line
power supplies.
PART NUMBER
MAXIMUM DUTY CYCLE
REFERENCE VOLTAGE
TURN-ON THRESHOLD
TURN-OFF THRESHOLD
UCC2800
100%
5 V
7.2 V
6.9 V
UCC2801
50%
5 V
9.4 V
7.4 V
UCC2802
100%
5 V
12.5 V
8.3 V
UCC2803
100%
4 V
4.1 V
3.6 V
UCC2804
50%
5 V
12.5 V
8.3 V
UCC2805
50%
4 V
4.1 V
3.6 V
Copyright
2003, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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.
1
2
3
4
8
7
6
5
COMP
FB
CS
RC
REF
V
CC
OUT
GND
D PACKAGE
(TOP VIEW)
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
ORDERING INFORMATION
TA
PACKAGE
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING
SOP D
Tape and reel
UCC2800QDREP
2800EP
SOP D
Tape and reel
UCC2801QDREP
2801EP
40
C to 125
C
SOP D
Tape and reel
UCC2802QDREP
2802EP
40
C to 125
C
SOP D
Tape and reel
UCC2803QDREP
2803EP
SOP D
Tape and reel
UCC2804QDREP
2804EP
SOP D
Tape and reel
UCC2805QDREP
2805EP
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design
guidelines are available at www.ti.com/sc/package.
block diagram
Ordering Information
UCC2
0
Q
PACKAGE
D = Plastic SOIC
PRODUCT OPTION
0 through 5
AUTOMOTIVE TEMPERATURE RANGE INDICATOR
D
TAPE and REEL INDICATOR
R
80
EP
ENHANCED PLASTIC INDICATOR
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
3
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
V
CC
voltage
w
12 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
V
CC
current
w
30 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output current, I
O
1 A
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output energy (Capacitive Load)
20
J
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Analog Inputs (FB, CS)
0.3 V to 6.3 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Dissipation at T
A
< +25
_
C (D package)
0.65 W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
65
_
C to 150
_
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lead temperature soldering 1,6 mm (1/16 inch) from case for 10 seconds
300
_
C
. . . . . . . . . . . . . . . . . . . . . . .
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.
Unless otherwise indicated, voltages are reference to ground and currents are positive into and negative out of the specified terminals.
w
In normal operation VCC is powered through a current limiting resistor. Absolute maximum of 12 V applies when VCC is driven from a low
impedance source such that ICC does not exceed 30 mA (which includes gate drive current requirement).
electrical characteristics, T
A
= 40
_
C to 125
_
C, V
CC
= 10 V (see Note 1), R
T
= 100 k
from REF to
RC, C
T
= 330 pF from RC to GND, 0.1 F capacitor from V
CC
to GND, 0.1 F capacitor from V
REF
to GND
and T
A
= T
J
(unless otherwise stated)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNITS
Reference Section
Output voltage
T
25
_
C
I
0 2
A
UCC2800/01/02/04
4.925
5.0
5.075
V
Output voltage
TJ = 25
_
C, I = 0.2 mA
UCC2803/05
3.94
4.0
4.06
V
Load regulation voltage
I = 0.2 mA to 5 mA
10
30
mV
Line regulation voltage
V
10 V to clamp
TJ = 25
_
C
1.9
mV/V
Line regulation voltage
VCC = 10 V to clamp
TJ = 40
_
C to 125
_
C
2.5
mV/V
Total variation voltage
See Note 5
UCC2800/01/02/04
4.88
5.0
5.1
V
Total variation voltage
See Note 5
UCC2803/05
3.9
4.0
4.08
V
Output noise voltage
f = 10 Hz to 10 kHz,
See Note 7
TJ = 25
_
C
130
V
Long term stability
1000 hours,
See Note 7
TA = 125
_
C
5
mV
Output short-circuit current
5
35
mA
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
4
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
electrical characteristics, T
A
= 40
_
C to 125
_
C, V
CC
= 10 V (see Note 1), R
T
= 100 k
from REF to
RC, C
T
= 330 pF from RC to GND, 0.1 F capacitor from V
CC
to GND, 0.1 F capacitor from V
REF
to GND
and T
A
= T
J
(unless otherwise stated)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNITS
Oscillator Section
Oscillator frequency
See Note 2
UCC2800/01/02/04
40
46
52
kHz
Oscillator frequency
See Note 2
UCC2803/05
26
31
36
kHz
Temperature stability
See Note 7
2.5
%
Amplitude peak-to-peak
2.25
2.4
2.55
V
Oscillator peak voltage
2.45
V
Error Amplifier Section
Input voltage
COMP = 2.5 V
UCC2800/01/02/04
2.44
2.5
2.56
V
Input voltage
COMP = 2.0 V
UCC2803/05
1.95
2.0
2.05
V
Input bias current
1
1
A
Open loop voltage gain
60
80
db
COMP sink current
FB = 2.7 V,
COMP = 1.1 V
0.3
3.5
mA
COMP source current
FB = 1.8 V,
COMP = REF 1.2 V
0.2
0.5
0.8
mA
Gain bandwidth product
See Note 7
2
MHz
PWM Section
Maximum duty cycle
UCC2800/02/03
97
99
100
%
Maximum duty cycle
UCC2801/04/05
48
49
50
%
Minimum duty cycle
COMP = 0 V
0
%
Current Sense Section
Gain
See Note 3
1.1
1.65
1.8
V/V
Maximum input signal
COMP = 5 V,
See Note 4
0.9
1
1.1
V
Input bias current
200
200
nA
CS blank time
50
100
150
ns
Over-current threshold voltage
1.42
1.55
1.68
V
COMP to CS offset voltage
CS = 0 V
0.45
0.9
1.35
V
Output Section (OUT)
IOUT = 20 mA
All parts
0.1
0.4
Low level output voltage
IOUT = 200 mA
All parts
0.35
0.9
V
Low-level output voltage
IOUT = 50 mA, VCC = 5 V
UCC2803/05
0.15
0.4
V
IOUT = 20 mA, VCC = 0 V
All parts
0.7
1.2
IOUT = 20 mA
All parts
0.15
0.4
High-level output voltage VSAT (VCC - OUT)
IOUT = 200 mA
All parts
1
1.9
V
High level out ut voltage VSAT (VCC OUT)
IOUT = 50 mA, VCC = 5 V
UCC2803/05
0.4
0.9
V
Rise time
CL = 1 nF
41
70
ns
Fall time
CL = 1 nF
44
75
ns
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
5
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
electrical characteristics, T
A
= 40
_
C to 125
_
C, V
CC
= 10 V (see Note 1), R
T
= 100 k
from REF to
RC, C
T
= 330 pF from RC to GND, 0.1 F capacitor from V
CC
to GND, 0.1 F capacitor from V
REF
to GND
and T
A
= T
J
(unless otherwise stated)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNITS
Undervoltage Lockout Section
UCC2800
6.6
7.2
7.8
Start threshold
See Note 6
UCC2801
8.6
9.4
10.2
V
Start threshold
See Note 6
UCC2802/04
11.5
12.5
13.5
V
UCC2803/05
3.7
4.1
4.5
UCC2800
6.3
6.9
7.5
Stop threshold
See Note 6
UCC2801
6.8
7.4
8
V
Stop threshold
See Note 6
UCC2802/04
7.6
8.3
9
V
UCC2803/05
3.2
3.6
4
UCC2800
0.12
0.3
0.48
Start to stop hysteresis
UCC2801
1.6
2
2.4
V
Start to stop hysteresis
UCC2802/04
3.5
4.2
5.1
V
UCC2803/05
0.2
0.5
0.8
Soft Start Section
COMP rise time
FB = 1.8 V,
Rise from 0.5 V to REF 1 V
4
10
ms
Overall Section
Start-up current
VCC < Start Threshold
0.1
0.2
mA
Operating supply current
FB = 0 V,
CS = 0 V
0.5
1
mA
VCC internal zener voltage
ICC = 10 mA,
See Notes 6 and 8
12
13.5
15
V
VCC internal zener voltage minus start
threshold voltage
See Note 6
UCC2802/04
0.5
1.0
V
NOTES:
1. Adjust VCC above the start threshold before setting at 10 V.
2. Oscillator frequency for the UCC2800, UCC2802 and UCC2803 is the output frequency.
Oscillator frequency for the UCC2801, UCC2804 and UCC2805 is twice the output frequency.
3. Gain is defined by:
A =
D
VCOMP
D
VCS
0
v
VCS
v
0.8 V.
4. Parameter measured at trip point of latch with Pin 2 at 0 V.
5. Total Variation includes temperature stability and load regulation.
6. Start Threshold, Stop Threshold and Zener Shunt Thresholds track one another.
7. Not production tested.
8. The device is fully operating in clamp mode as the forcing current is higher than the normal operating supply current.
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
6
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
detailed terminal descriptions
COMP
COMP is the output of the error amplifier and the input of the PWM comparator.
Unlike other devices, the error amplifier in the UCC2800 family is a true, low output-impedance, 2 MHz
operational amplifier. As such, the COMP terminal can both source and sink current. However, the error
amplifier is internally current limited, so that one can command zero duty cycle by externally forcing COMP to
GND.
The UCC2800 family features built-in full cycle Soft Start. Soft Start is implemented as a clamp on the maximum
COMP voltage.
CS
CS is the input to the current sense comparators. The UCC2800 family has two different current sense
comparators: the PWM comparator and an over-current comparator.
The UCC2800 family contains digital current sense filtering, which disconnects the CS terminal from the current
sense comparator during the 100 ns interval immediately following the rising edge of the OUT pin. This digital
filtering, also called leading-edge blanking, means that in most applications, no analog filtering (RC filter) is
required on CS. Compared to an external RC filter technique, the leading-edge blanking provides a smaller
effective CS to OUT propagation delay. Note, however, that the minimum non-zero On-Time of the OUT signal
is directly affected by the leading-edge-blanking and the CS to OUT propagation delay.
The over-current comparator is only intended for fault sensing, and exceeding the over-current threshold will
cause a soft start cycle.
FB
FB is the inverting input of the error amplifier. For best stability, keep FB lead length as short as possible and
FB stray capacitance as small as possible.
ground (GND)
GND is reference ground and power ground for all functions on this part.
OUT
OUT is the output of a high-current power driver capable of driving the gate of a power MOSFET with peak
currents exceeding
"
750 mA. OUT is actively held low when V
CC
is below the UVLO threshold.
The high-current power driver consists of FET output devices, which can switch all of the way to GND and all
of the way to V
CC
. The output stage also provides a very low impedance to overshoot and undershoot. This
means that in many cases, external schottky clamp diodes are not required.
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
7
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
detailed descriptions (continued)
RC
RC is the oscillator timing pin. For fixed frequency operation, set timing capacitor charging current by connecting
a resistor from REF to RC. Set frequency by connecting timing capacitor from RC to GND. For best perfomance,
keep the timing capacitor lead to GND as short and direct as possible. If possible, use separate ground traces
for the timing capacitor and all other functions.
The frequency of oscillation can be estimated with the following equations:
UCC2800 01 02 04 : F
+
1.5
R
C
UCC2803 UCC2805 : F
+
1.0
R
C
where frequency is in Hz, resistance is in ohms, and capacitance is in farads. The recommended range of timing
resistors is between 10k and 200k and timing capacitor is 100 pF to 1000 pF. Never use a timing resistor less
than 10k.
To prevent noise problems, bypass V
CC
to GND with a ceramic capacitor as close to the V
CC
pin as possible.
An electrolytic capacitor may also be used in addition to the ceramic capacitor.
voltage reference (REF)
REF is the voltage reference for the error amplifier and also for many other functions on the IC. REF is also
used as the logic power supply for high speed switching logic on the IC.
When V
CC
is greater than 1 V and less than the UVLO threshold, REF is pulled to ground through a 5k ohm
resistor. This means that REF can be used as a logic output indicating power system status. It is important for
reference stability that REF is bypassed to GND with a ceramic capacitor as close to the pin as possible. An
electrolytic capacitor may also be used in addition to the ceramic capacitor. A minimum of 0.1
F ceramic is
required. Additional REF bypassing is required for external loads greater than 2.5 mA on the reference.
To prevent noise problems with high speed switching transients, bypass REF to ground with a ceramic capacitor
very close to the IC package.
power (V
CC
)
V
CC
is the power input connection for this device. In normal operation V
CC
is powered through a current limiting
resistor. Although quiescent V
CC
current is very low, total supply current will be higher, depending on OUT
current. Total V
CC
current is the sum of quiescent V
CC
current and the average OUT current. Knowing the
operating frequency and the MOSFET gate charge (Q
g
), average OUT current can be calculated from:
I
OUT
+
Q
g
F.
(1)
(2)
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
8
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
PARAMETER MEASUREMENT INFORMATION
Figure 1
Oscillator
The UCC3800/1/2/3/4/5 oscillator generates a sawtooth waveform
on RC. The rise time is set by the time constant of RT and CT. The
fall time is set by CT and an internal transistor on-resistance of
approximately 125. During the fall time, the output is off and the
maximum duty cycle is reduced below 50% or 100% depending on
the part number. Larger timing capacitors increase the discharge
time and reduce the maximum duty cycle and frequency.
Figure 2
Error Amplifier
Gain/Phase Response
Figure 3
UCC1803/05 V
REF
vs. V
CC
; I
LOAD
= 0.5 mA
Figure 4
UCC1800/01/02/04 Oscillator Frequency
vs. R
T
and C
T
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
9
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
Figure 5
UCC1803/05 Oscillator Frequency vs.
R
T
and C
T
Figure 6
UCC1800/02/03 Maximum Duty Cycle vs.
Oscillator Frequency
Figure 7
UCC1801/04/05 Maximum Duty Cycle vs.
Oscillator Frequency
Figure 8
UCC1800 I
CC
vs. Oscillator Frequency
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
10
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
Figure 9
UCC1805 I
CC
vs Oscillator Frequency
Figure 10
Dead Time vs. C
T
, R
T
= 100k
Figure 11
COMP to CS Offset vs. Temperature, CS = 0 V
UCC2800/2801/2802/2803/2804/2805-EP
LOW-POWER BICMOS CURRENT-MODE PWM
SGLS135B SEPTEMBER 2002 REVISED MARCH 2003
11
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
MECHANICAL DATA
D (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
8 PINS SHOWN
8
0.197
(5,00)
A MAX
A MIN
(4,80)
0.189
0.337
(8,55)
(8,75)
0.344
14
0.386
(9,80)
(10,00)
0.394
16
DIM
PINS **
4040047/E 09/01
0.069 (1,75) MAX
Seating Plane
0.004 (0,10)
0.010 (0,25)
0.010 (0,25)
0.016 (0,40)
0.044 (1,12)
0.244 (6,20)
0.228 (5,80)
0.020 (0,51)
0.014 (0,35)
1
4
8
5
0.150 (3,81)
0.157 (4,00)
0.008 (0,20) NOM
0
8
Gage Plane
A
0.004 (0,10)
0.010 (0,25)
0.050 (1,27)
NOTES: A. All linear dimensions are in inches (millimeters).
B. This drawing is subject to change without notice.
C. Body dimensions do not include mold flash or protrusion, not to exceed 0.006 (0,15).
D. Falls within JEDEC MS-012
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Post Office Box 655303
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Copyright
2003, Texas Instruments Incorporated
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