參數(shù)資料
型號(hào)： L6566BH
廠商： STMICROELECTRONICS
元件分類： 穩(wěn)壓器
英文描述： SWITCHING CONTROLLER, 300 kHz SWITCHING FREQ-MAX, PDSO16
封裝： ROHS COMPLIANT, SOP-16
文件頁(yè)數(shù)： 22/48頁(yè)
文件大?。?/td> 768K
代理商： L6566BH
L6566BH
Application information
Doc ID 16610 Rev 1
29/48
relationship 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
.
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 L6566BH 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 CMOD 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 RT on
pin OSC). Hence, the voltage across CMOD will be a symmetric triangle, whose frequency fm
is determined by CMOD. By connecting a resistor RMOD from FMOD to OSC, the current
sourced by pin OSC will be modulated according a triangular profile at a frequency fm. If
RMOD is considerably higher than RT, as normally is, both fm and the symmetry of the
triangle will be little affected.
With this arrangement it is possible to set, nearly independently, the frequency deviation
Δf
sw and the modulating frequency fm, which define the modulation index:
L6566BH
OSC
6
RT
FMOD
13
RMOD
CMOD
1.5 V
0.5 V
0 V
1 V
相關(guān)PDF資料
PDF描述
L6585D 0.6 A POWER FACTOR AND FLUORESCENT LIGHT CONTROLLER, 250 kHz SWITCHING FREQ-MAX, PDSO20
L6585DTR 0.6 A POWER FACTOR AND FLUORESCENT LIGHT CONTROLLER, 250 kHz SWITCHING FREQ-MAX, PDSO20
L6590AN 0.7 A SWITCHING REGULATOR, 74 kHz SWITCHING FREQ-MAX, PDIP8
L6590D013TR 0.7 A SWITCHING REGULATOR, 74 kHz SWITCHING FREQ-MAX, PDSO16
L6590D 0.7 A SWITCHING REGULATOR, 74 kHz SWITCHING FREQ-MAX, PDSO16
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
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(kāi)關(guān)頻率:27 KHz 上升時(shí)間: 下降時(shí)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(fēng)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(kāi)關(guān)頻率:27 KHz 上升時(shí)間: 下降時(shí)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(fēng)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
L6567 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:HIGH VOLTAGE DRIVER FOR CFL
L6567D 制造商:STMicroelectronics 功能描述:CFL DRVR 18V 14SOP - Rail/Tube
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*