DataSheet.es    


PDF LCS705HG Data sheet ( Hoja de datos )

Número de pieza LCS705HG
Descripción (LCS700 - LCS708) Integrated LLC Controller
Fabricantes Power Integrations 
Logotipo Power Integrations Logotipo



Hay una vista previa y un enlace de descarga de LCS705HG (archivo pdf) en la parte inferior de esta página.


Total 26 Páginas

No Preview Available ! LCS705HG Hoja de datos, Descripción, Manual

www.DataSheet.co.kr
LCS700-708
HiperLCSFamily
Integrated LLC Controller, High-Voltage
Power MOSFETs and Drivers
Product Highlights
Features
LLC half-bridge power stage incorporating controller, high and
low-side gate drives, and high-voltage power MOSFETs
Eliminates up to 30 external components
High maximum operating frequency of 1 MHz
Nominal steady-state operation up to 500 kHz
Dramatically reduces magnetics size and allows use of
SMD ceramic output capacitors
Precise duty symmetry balances output rectifier current,
improving efficiency
50% ±0.3% typical at 300 kHz
Comprehensive fault handling and current limiting
Programmable brown-in/out thresholds and hysteresis
Undervoltage (UV) and overvoltage (OV) protection
Programmable over-current protection (OCP)
Short-circuit protection (SCP)
Over-temperature protection (OTP)
Programmable dead-time for optimized design
Programmable burst mode maintains regulation at no-load and
improves light load efficiency
Programmable soft-start time and delay before soft-start
Accurate programmable minimum and maximum frequency
limits
Single package designed for high-power and high-frequency
Reduces assembly cost and reduces PCB layout loop areas
Simple single clip attachment to heat sink
Exposed thermal pad connected to ground potential – no
insulators required between package and heat sink
Staggered pin arrangement for simple PC board routing
and high-voltage creepage requirements
Paired with HiperPFS PFC product gives complete, high
efficiency, low part count PSU solutions
Applications
High-efficiency power supplies (80 PLUS Silver, Gold and
Platinum)
LCD TV power supplies
LED street and area lighting
Printer power supplies
Audio amplifier
Description
The HiperLCS is an integrated LLC power stage incorporating a
multi-function controller, high-side and low-side gate drivers,
plus two power MOSFETs in a half-bridge configuration. Figure
1 shows a simplified schematic of a HiperLCS based power stage
where the LLC resonant inductor is integrated into the transformer.
The variable frequency controller provides high efficiency by
switching the power MOSFETs at zero voltage (ZVS), eliminating
switching losses. 
B+
VCCH
D
Standby
Supply
VCC
CONTROL
HB
+V
HV DC
Input
B-
OV/UV
VREF
RFMAX
DT/BF
RBURST
FB
G
IS
HiperLCS
S1/S2
RTN
LLC Feedback Circuit
PI-6159-060211
Figure 1. Typical Application Circuit – LCD TV and PC Main Power Supply.
Output Power Table
Product
Maximum Practical Power1
LCS700HG
110 W
LCS701HG
170 W
LCS702HG
220 W
LCS703HG
275 W
LCS705HG
350 W
LCS708HG
440 W
Table 1. Output Power Table.
Notes:
1. Maximum practical power is the power the part can deliver when properly
mounted to a heat sink and a maximum heat sink temperature of 90 °C.
www.powerint.com
June 2011
Datasheet pdf - http://www.DataSheet4U.net/

1 page




LCS705HG pdf
www.DataSheet.co.kr
LCS700-708
HiperLCS Basic Operation
The HiperLCS is designed for half-bridge LLC converters, which
are high-efficiency resonant, variable frequency converters. The
HiperLCS is an LLC controller chip with built-in drivers and
half-bridge MOSFETs.
LLC converters require a fixed dead-time between switching
half-cycles. The dead-time, maximum frequency at start-up,
and burst threshold frequencies, are programmed with a resistor
divider on the DT/BF pin from the VREF to the GROUND pins.
The FEEDBACK (FB) pin is the frequency control input for the
feedback loop. Frequency is proportional to FEEDBACK pin
current. The FEEDBACK pin V-I characteristic resembles a
diode to ground.
Burst Mode
If the frequency commanded by the FEEDBACK pin current
exceeds the upper burst threshold frequency (fSTOP, ISTOP)
programmed by the resistor divider on the DT/BF pin, the output
MOSFETs will turn off, and will resume switching when the current
drops below the value which corresponds to the frequency
efirqsut aalptoprtohxeimloawtieornb, burusrtstthmreosdheolcdofnretrqoul erensceym(fbSTlAeRsT,aIShTAyRsTt).erAetsica
controller where
and repeats. An
the frequency ramps
external component
nfreotmwofSrTkARcTotnonfeSTcOtPe, dstforopms
the VREF pin to the FEEDBACK pin determines the minimum
and start-up FEEDBACK pin currents, and thus the minimum
and start-up switching frequencies. A soft-start capacitor in
this network determines soft-start timing.
The VREF pin provides a nominal 3.4 V as a reference for this
FEEDBACK pin external network and other functions. Maximum
current from this pin must be ≤4 mA.
The Dead-Time/Burst Frequency (DT/BF) pin also has a diode-to-
ground V-I characteristic. A resistor divider from VREF to GROUND
programs dead-time, maximum start-up
and the burst threshold frequencies. The
scwuritrcehnitnfglofwreinqguefnrocym(ftMhAeX),
rreessiissttoorrsdsiveidleecrtstofrtohme D3Td/BisFcrpeitne,dbeutersrmt tihnreesshfMoAlXd.
The ratio of the
frequency ratios,
which are fixed fractions of fMAX.
The OV/UV pin senses the high-voltage B+ input through a
resistor divider. It implements brown-in, brown-out, and OV
with hysteresis. The ratios of these voltages are fixed; the user
must select the resistor divider ratio such that the brown-in
voltage is below the minimum nominal bulk (input) voltage
regulation set-point to ensure start-up, and the OV (lower)
restart voltage is above the maximum nominal bulk voltage
set-point, to ensure that the LCS will restart after a voltage swell
event that triggers the OV upper threshold. If different brown-in
to brown-out to OV ratios are required, external circuitry needs
to be added to the resistor divider.
VCC Pin UVLO
The VCC pin has an internal UVLO function with hysteresis. The
HiperLCS will not start until the voltage exceeds the VCC start
tthhereVsChoCldSVhUuVtLdOo(+w). nHTiphererLsChoSldwVillUtVuLOr(n-). off when the VCC drops to
www.powerint.com
VCCH Pin UVLO
The VCCH pin is the supply pin for the high-side driver. It also
has a UVLO function similar to the VCC pin, with a threshold
lower than the VCC pin. This is to allow for a VCCH voltage that
is slightly lower than VCC because the VCCH pin is fed by a
bootstrap diode and series current-limiting resistor from the
VCC supply.
Start-Up and Auto-Restart
Before start-up the FEEDBACK pin is internally pulled up to the
VREF pin to discharge the soft-start capacitor and to keep the
output MOSFETs off. When start-up commences the internal
pull-up transistor turns off, the soft-start capacitor charges, the
oduimtpinuitsshebse,gtihneswswitcitchhininggaftrfeMqAuX,etnhceyFdErEoDpsB,AaCnKd
pin
the
current
PSU output
rises. When the output reaches the voltage set-point, the
optocoupler will conduct, closing the loop and regulating the output.
Whenever the VCC pin is powered up, the DT/BF pin goes into
high impedance mode for 500 ms in order to sense the voltage
divider ratio and select the Burst Threshold. This setting is
stored until the next VCC recycle. The DT/BF pin then goes into
normal mode, resembling a diode to ground, and the sensed
current continuously sets the fMAX frequency. The burst threshold
frequencies are fixed fractions of fMAX. The internal oscillator
runs the internal
internal pull-up is
counters
on.
at
fMAX
whenever
the
FEEDBACK
pin
When a fault is detected on the IS, OV/UV, or VCC pin (UVLO),
the internal FEEDBACK pin pull-up transistor turns on for
131,072 clock cycles, to discharge the soft-start capacitor
completely, then a restart is attempted. The first power-up after
a VCC recycle only waits 1024 cycles, including the condition
where the OV/UV pin rises above the brown-in voltage for the
first time, after VCC is powered up.
Remote-Off
Remote-off can be invoked by pulling down the OV/UV pin to
ground, or by pulling up the IS pin to >0.9 V. Both will invoke a
131,072 cycle restart cycle. VCC can also be pulled down to
shut the device off, but when it is pulled up, the FEEDBACK pin
is pulled up to the VREF pin to discharge the soft-start capacitor
for only 1024 fMAX clock cycles. If this scheme is used, the
designer must ensure that the time the VCC is pulled down,
plus 1024 cycles, is sufficient to discharge the soft-start
capacitor, or if not, that the resulting lower starting frequency is
high enough so as not to cause excessive primary currents that
may cause the over-current protection to trip.
Current Sense
The IS pin senses the primary current. It resembles a reverse
diode to the GROUND pin. It is tolerant of negative voltages
provided the negative current is limited to <5 mA. Therefore it
must be connected to the current sense resistor (or primary
capacitive voltage divider + sense resistor) via a series current
limiting resistor of >220 Ω. Thus it can accept an AC waveform
and does not need a rectifier or peak detector circuit. If the IS
pin senses a nominal positive peak voltage of 0.5 V for 7
consecutive cycles, an auto-restart will be invoked. The IS pin
also has a second, higher threshold at nominally 0.9 V, which
will invoke an auto-restart with a single pulse. The minimum
5
Rev. B 062011
Datasheet pdf - http://www.DataSheet4U.net/

5 Page





LCS705HG arduino
www.DataSheet.co.kr
LCS700-708
Key Design Details
The LLC converter is a variable frequency resonant converter.
As input voltage decreases, the frequency must decrease in
order to maintain output regulation. To a lesser extent, as load
reduces the frequency must increase. When the converter is
operating at the series resonant frequency, the frequency changes
very little with load. The minimum operating frequency required
occurs at brownout (minimum input voltage), at full load.
Operating Frequency Selection
For lowest cost, and smallest transformer size with the least
amount of copper, the recommended nominal operating frequency
is ~250 kHz. This allows the use of low-cost ceramic output
capacitors in place of electrolytic capacitors, especially at
higher output voltages (≥12 V). If the core and bobbin used
exhibits too much leakage inductance for 250 kHz, operation at
180 kHz also results in excellent performance. For optimal
efficiency at 250 kHz, AWG #44 (0.05 mm) Litz is recommended
for the primary, and AWG #42 (0.07 mm) for the secondary
winding. Thicker gauge lower cost Litz can be used at the
expense of increased copper loss and lower efficiency. Litz
gauge (AWG #38 or 0.1 mm) is optimal for very low frequencies
(60-70 kHz), requires much larger transformers and greater
lengths of Litz wire.
For nominal operating frequencies even as low as 130 kHz, the
use of PC44 or equivalent core material is recommended for
reduced losses. For a given transformer design, shifting the
frequency up (by substituting a smaller resonant capacitor), will
reduce core loss (due
increase copper loss.
tCooreredulocsesdisAaCsflturoxndgeenrsfiutyncBtAioCn) aonfdflux
density than of frequency. The increased frequency increases
copper loss due to eddy current losses.
Nominal operating frequencies >300 kHz start to lose significant
efficiency due to increased eddy current losses in the copper,
and due to the fact that a more significant percentage of time is
spent on the primary slew time (ZVS transition time) which
erodes the percentage of time that power is transferred to the
secondary.
Resonant Tank and Transformer Design
Please refer to the Application Note AN-55 for guidance on
using the PIXls HiperLCS spreadsheet which assists in the
entire design process.
Primary Inductance
The optimal powertrain design for the HiperLCS uses a primary
inductance that results in minimal loss of ZVS at any steady-
state condition. Some loss of ZVS during non-steady-state
conditions is acceptable. Reducing primary inductance
produces higher magnetizing current which increases the range
of ZVS operation, but the increased magnetizing current
increases losses and reduces efficiency.
The calculation of the primary inductance to be used for a
first-pass design is based on device size, rated load, minimum
input voltage, and desired operating frequency. It is provided in
the PIXls spreadsheet.
integrated transformer
(hLiPgRhI isletahkeagperiminadruycitnadnuccet)a, nocreinotfhaencase
of the use of an external series inductance, the sum of this
inductance and the transformer primary inductance.
Leakage Inductance
The parameter KRATIO is a function of leakage inductance:
K =RATIO
L PRI
L RES
-1
The recommended KRATIO is from 2.5 - 7. This determines the
acceptable range of leakage inductance.
LseREpSairsattheesleeraieksaginediuncdtuocr tiasnucseedin,
an integrated transformer; if a
it is the sum of this inductance
and the leakage inductance of the transformer.
AreglouwlaKtioRnATIaOt(hthigehmleiankimagueminindpuucttavnocltea)gme,aaynndomt baey
capable
show
of
increased transformer copper losses due to the leakage flux. A
hRiMghSKcRuArTrIOen(ltoswatleloawka-lgineei,nadnudctraenqcueir)ewailllohwaevrephriigmhapryeiankduacntdance
to achieve ZVS operation over a suitably wide range, which
increases the resonant circulating current, reducing efficiency.
The core and bobbin designs available to the designer may limit
the adjustability of leakage inductance. Fortunately, excellent
performance can be achieved over a relatively wide range of
leakage inductance values.
TtoheopKeRrAaTItOedinireocrtdlyeraftfoecmtsaitnhteaifnrerqeugeunlactyiornanogveerththaet
the LLC needs
input voltage
range. Increasing
lowering fMIN.
KRATIO
increases
this
frequency
range,
A low fMIN is only a potential problem for low frequency designs
which typically run at higher nominal BAC. This may allow the
core to reach saturation when operating at fMIN. Operating at
fMIN occurs when the input voltage is at a minimal (input
brown-out).
For a design with a separate resonant inductor, running the
inductance on the low side of the
the size and cost of the inductor.
range
(KRATIO
=
7),
minimizes
Adjusting Leakage Inductance
Sectioned bobbins (separated primary and secondary) are
commonly used for LLC converters. Increasing or decreasing
both primary and secondary turns (while maintaining turns ratio)
will change the leakage inductance proportionally to the square
of primary turns.
If the leakage inductance is too high, one possible solution is to
use a 3-section bobbin, where the secondary is in the middle
section, and the primary winding is split into 2 halves connected
in series.
Lastly, if the leakage inductance is too low an external inductor
may be added.
www.powerint.com
11
Rev. B 062011
Datasheet pdf - http://www.DataSheet4U.net/

11 Page







PáginasTotal 26 Páginas
PDF Descargar[ Datasheet LCS705HG.PDF ]




Hoja de datos destacado

Número de piezaDescripciónFabricantes
LCS705HG(LCS700 - LCS708) Integrated LLC ControllerPower Integrations
Power Integrations

Número de piezaDescripciónFabricantes
SLA6805M

High Voltage 3 phase Motor Driver IC.

Sanken
Sanken
SDC1742

12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters.

Analog Devices
Analog Devices


DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares,
permitiéndote verlos en linea o descargarlos en PDF.


DataSheet.es    |   2020   |  Privacy Policy  |  Contacto  |  Buscar