參數(shù)資料
型號： L6566B
廠商： 意法半導體
英文描述： Multi-mode controller for SMPS
中文描述： 多模式開關(guān)電源控制器
文件頁數(shù)： 31/51頁
文件大?。?/td> 401K
代理商： L6566B
L6566B
Application information
31/51
between the detected event and the oscillator, occasionally the device could stop after the
third detection.
This condition is latched as long as the device is supplied. While it is disabled, however, no
energy is coming from the self-supply circuit; hence the voltage on the Vcc capacitor will
decay and cross the UVLO threshold after some time, which clears the latch. The internal
start-up generator is still off, then the Vcc voltage still needs to go below its restart voltage
before the Vcc capacitor is charged again and the device restarted. Ultimately, this will result
in a low-frequency intermittent operation (Hiccup-mode operation), with very low stress on
the power circuit. This special condition is illustrated in the timing diagram of
Figure 18 on
page 30
.
5.8
Frequency modulation
To alleviate converter’s EMI emissions and reduce cost and size of the line filter, it is
advantageous to modulate its switching frequency, so that the resulting spread-spectrum
action distributes the energy of each harmonic of the switching frequency over a number of
side-band harmonics. Their overall energy will be unchanged but the individual amplitudes
will be smaller. This is what naturally occurs with QR operation, due to the twice-mains-
frequency ripple appearing on the input bulk capacitor, which translates into different DCM-
CCM boundary frequencies.
The L6566B is provided with a dedicated pin, FMOD (6), to perform this function if FF mode
is selected.
Figure 19. Frequency modulation circuit
With reference to
Figure 19
, the capacitor C
MOD
is connected from FMOD to ground and is
alternately charged and discharged between 0.5 and 1.5 V by internal current generators
sourcing and sinking the same current (three times the current defined by the resistor R
T
on
pin OSC). Hence, the voltage across C
MOD
will be a symmetric triangle, whose frequency f
m
is determined by C
MOD
. By connecting a resistor R
MOD
from FMOD to OSC, the current
sourced by pin OSC will be modulated according a triangular profile at a frequency f
m
. If
R
MOD
is considerably higher than R
T
, as normally is, both f
m
and the symmetry of the
triangle will be little affected.
With this arrangement it is possible to set, nearly independently, the frequency deviation
f
sw
and the modulating frequency f
m
, which define the modulation index:
L6566B
OSC
6
R
T
FMOD
13
R
MOD
C
MOD
1.5 V
0.5 V
0 V
1 V
相關(guān)PDF資料
PDF描述
L6566BTR Multi-mode controller for SMPS
L6567 HIGH VOLTAGE DRIVER FOR CFL
L6567D HIGH VOLTAGE DRIVER FOR CFL
L6571B High Voltage Half Bridge Driver with Oscillator(帶晶振的高電壓半橋驅(qū)動器)
L6585D PFC and Ballast Control IC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
L6566B_08 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Multi-mode controller for SMPS
L6566BH 功能描述:電流型 PWM 控制器 Multimode Controller SMPS 800V <3mA RoHS:否 制造商:Texas Instruments 開關(guān)頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風格:SMD/SMT 封裝 / 箱體:TSSOP-14
L6566BHTR 功能描述:電流型 PWM 控制器 MULTIMODE CONTROLLER SMPS 8V 3 mA RoHS:否 制造商:Texas Instruments 開關(guān)頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風格:SMD/SMT 封裝 / 箱體:TSSOP-14
L6566BTR 功能描述:電流型 PWM 控制器 MultiMode Controller for SMPS RoHS:否 制造商:Texas Instruments 開關(guān)頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風格:SMD/SMT 封裝 / 箱體:TSSOP-14
L6566BTR-CUT TAPE 制造商:ST 功能描述:L6566B Series 23 V 4.6 mA SMPS Multi-Mode Controller Surface Mount - SOIC-16N
發(fā)布緊急采購，3分鐘左右您將得到回復。

采購需求

(若只采購一條型號，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進入我的后臺，查看報價

*型號 *數(shù)量 廠商 批號 封裝
添加更多采購

我的聯(lián)系方式

*
*
*