900,000+ datasheet pdf search and download

Datasheet4U offers most rated semiconductors data sheet pdf






etcTI

UCC38502 Datasheet Preview

UCC38502 Datasheet

BiCMOS PFC/PWM Combination Controller

No Preview Available !

UCC28500, UCC28501, UCC28502, UCC28503
UCC38500, UCC38501, UCC38502, UCC38503
SLUS419C − AUGUST 1999 − REVISED NOVEMBER 2001
BiCMOS PFC/PWM
COMBINATION CONTROLLER
FEATURES
D Combines PFC and Downstream Converter
Controls
D Controls Boost Preregulator to Near-Unity
Power Factor
D Accurate Power Limiting
D Improved Feedforward Line Regulation
D Peak Current-Mode Control in Second Stage
D Programmable Oscillator
D Leading-Edge/Trailing-Edge Modulation for
Reduced Output Ripple
D Low Start-up Supply Current
D Synchronized Second Stage Start-Up, with
Programmable Soft-start
D Programmable Second Stage Shutdown
DESCRIPTION
The UCC2850x family provides all of the control
functions necessary for an active power-factor-
corrected preregulator and a second-stage dc-to- dc
converter. The controller achieves near-unity power
factor by shaping the ac input line current waveform to
correspond to the ac input-line voltage using average
current-mode control. The dc-to-dc converter uses
peak current-mode control to perform the step-down
power conversion.
The PFC stage is leading-edge modulated while the
second stage is trailing-edge synchronized to allow for
minimum overlap between the boost and PWM
switches. This reduces ripple current in the bulk-output
capacitor.In order to operate with over three-to-one
range of input-line voltages, a line feedforward (VFF) is
used to keep input power constant with varying input
voltage. Generation of VFF is accomplished using IAC in
conjunction with an external single-pole filter. This not
only reduces external parts count, but also avoids the
use of high-voltage components, offering a lower-cost
solution. The multiplier then divides the line current by
the square of VFF.
The UCC2850x PFC section incorporates a low
offset-voltage amplifier with 7.5-V reference, a
highly-linear multiplier capable of a wide current range,
a high-bandwidth, low offset-current amplifier, with a
novel noise-attenuation configuration, PWM
comparator and latch, and a high-current output driver.
Additional PFC features include over-voltage
protection, zero-power detection to turn off the output
when VAOUT is below 0.33 V and peak current and
power limiting.
The dc-to-dc section relies on an error signal generated
on the secondary-side and processes it by performing
peak current mode control. The dc-to-dc section also
features current limiting, a controlled soft-start, preset
operating range with selectable options, and 50%
maximum duty cycle.
The UCC28500 and UCC28502 have a wide UVLO
threshold (16.5 V/10 V) for bootstrap bias supply
operation. The UCC28501 and UCC28503 are
designed with a narrow UVLO range (10.5 V/10 V) more
suitable for fixed bias operation. The UCC28500 and
UCC28501 have a narrow UVLO threshold for PWM
stage (to allow operation down to 75% of nominal bulk
voltage), while the UCC28502 and UCC38503 are
configured for a much wider operation range for the
PWM stage (down to 50% of bulk nominal voltage).
Available in 20-pin N and DW packages.
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.
www.ti.com
Copyright 2001, Texas Instruments Incorporated
1




etcTI

UCC38502 Datasheet Preview

UCC38502 Datasheet

BiCMOS PFC/PWM Combination Controller

No Preview Available !

UCC28500, UCC28501, UCC28502, UCC28503
UCC38500, UCC38501, UCC38502, UCC38503
SLUS419C − AUGUST 1999 − REVISED NOVEMBER 2001
absolute maximum ratings over operating free-air temperature (unless otherwise noted)}
Supply Voltage VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 V
Gate Drive Current
Continuous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.2 A
Pulsed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 A
Input Voltage
ISENSE1, ISENSE2, MOUT, VSENSE, OVP/ENBL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 V
CAI, MOUT, CT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 V
PKLMT, VERR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 V
Input Current
RSET, RT, IAC, PKLMT, ENA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 mA
VCC (no switching) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 mA
Maximum Negative Voltage GT1, GT2, PKLMT, MOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 W
Storage temperature Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
Junction temperature TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −55°C to 125°C
Lead temperature (soldering, 10 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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.
Currents are positive into, negative out of the specified terminal. Consult Packaging Section of Databook for thermal limitations and
considerations of packages. All voltages are referenced to GND.
AVAILABLE OPTIONS
PFC THRESHOLD
PACKAGED DEVICES
TJ
UVLO TURN−ON
THRESHOLD (V)
UVLO2
HYSTERESIS
(V)
PLASTIC DIP
(N)
SMALL OUTLINE
(DW)
16
1.2
UCC28500N
UCC28500DW
–40°C to 85°C
10.5
16
1.2
UCC28501N
UCC28501DW
3.0
UCC28502N
UCC28502DW
10.5
3.0
UCC28503N
UCC28503DW
16
1.2
UCC38500N
UCC38500DW
0°C to 70°C
10.5
16
1.2
UCC38501N
UCC38501DW
3.0
UCC38502N
UCC38502DW
10.5
3.0
UCC38503N
UCC38503DW
The DW package is available taped and reeled. Add TR suffix to device type (e.g. UCC38500DWTR)
to order quantities of 2000 devices per reel.
N PACKAGE
(TOP VIEW)
DW PACKAGE
(TOP VIEW)
VAOUT
RT
VSENSE
OVP/ENBL
CT
GND
VERR
ISENSE2
VCC
GT2
1
2
3
4
5
6
7
8
9
10
20 VREF
19 VFF
18 IAC
17 MOUT
16 ISENSE1
15 CAOUT
14 PKLMT
13 SS2
12 GT1
11 PWRGND
VAOUT
RT
VSENSE
OVP/ENBL
CT
GND
VERR
ISENSE2
VCC
GT2
1
2
3
4
5
6
7
8
9
10
20 VREF
19 VFF
18 IAC
17 MOUT
16 ISENSE1
15 CAOUT
14 PKLMT
13 SS2
12 GT1
11 PWRGND
2 www.ti.com


Part Number UCC38502
Description BiCMOS PFC/PWM Combination Controller
Maker etcTI
PDF Download

UCC38502 Datasheet PDF






Similar Datasheet

1 UCC38500 BiCMOS PFC/PWM Combination Controller
etcTI
2 UCC38501 BiCMOS PFC/PWM Combination Controller
etcTI
3 UCC38502 BiCMOS PFC/PWM Combination Controller
etcTI
4 UCC38503 BiCMOS PFC/PWM Combination Controller
etcTI





Part Number Start With

0    1    2    3    4    5    6    7    8    9    A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z



Site map

Webmaste! click here

Contact us

Buy Components

Privacy Policy