參數(shù)資料
型號: L6599
廠商: 意法半導體
英文描述: High-voltage resonant controller
中文描述: 高壓諧振控制器
文件頁數(shù): 24/36頁
文件大?。?/td> 591K
代理商: L6599
Application information
L6599
24/36
Figure 30. Lossless current sensing technique, with capacitive shunt
The device is equipped with a current sensing input (pin 6, ISEN) and a sophisticated
overcurrent management system. The ISEN pin is internally connected to the input of a first
comparator, referenced to 0.8V, and to that of a second comparator referenced to 1.5V. If the
voltage externally applied to the pin by either circuit in
Figure 29
or
Figure 30
exceeds 0.8V
the first comparator is tripped and this causes an internal switch to be turned on and
discharge the soft-start capacitor C
SS
(see
Chapter 7.3: Soft-start
). This will quickly
increase the oscillator frequency and thereby limit energy transfer. The discharge will go on
until the voltage on the ISEN pin has dropped by 50mV; this, with an averaging time in the
range of 10/f
min
, ensures an effective frequency rise. Under output short circuit, this
operation results in a nearly constant peak primary current.
It is normal that the voltage on the ISEN pin may overshoot above 0.8V; however, if the
voltage on the ISEN pin reaches 1.5V, the second comparator will be triggered, the L6599
will shutdown and latch off with both the gate-drive outputs and the PFC_STOP pin low,
hence turning off the entire unit. The supply voltage of the IC must be pulled below the
UVLO threshold and then again above the start-up level in order to restart. Such an event
may occur if the soft-start capacitor C
SS
is too large, so that its discharge is not fast enough
or in case of transformer's magnetizing inductance saturation or a shorted secondary
rectifier.
In the circuit shown in
Figure 29
where a sense resistor R
S
in series to the source of the
low-side MOSFET is used, note the particular connection of the resonant capacitor. In this
way the voltage across R
S
is related to the current flowing through the high-side MOSFET
and is positive most of the switching period, except for the time needed for the resonant
current to reverse after the low-side MOSFET has been switched OFF. Assuming that the
time constant of the RC filter is at least ten times the minimum switching frequency f
min
, the
approximate value of R
S
can be found using the empirical equation:
where I
Crpkx
is the maximum desired peak current flowing through the resonant capacitor
and the primary winding of the transformer, which is related to the maximum load and the
minimum input voltage.
pk
L6599
6 ISEN
Cr
R
A
R
B
1N4148
C
B
C
A
1N4148
τ
10
f
min
V
Crpk
I
Cr
R
S
Vs
I
Crpkx
--------------
------------------
I
Crpkx
I
Crpkx
--------------
=
相關(guān)PDF資料
PDF描述
L6599D High-voltage resonant controller
L6599N High-voltage resonant controller
L6599TR High-voltage resonant controller
L6701 3 Phase Controller for VR10, VR9 and K8 CPUs
L6701TR 3 Phase Controller for VR10, VR9 and K8 CPUs
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
L6599_0807 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:High-voltage resonant controller
L6599A 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Improved high-voltage resonant controller
L6599AD 功能描述:電壓模式 PWM 控制器 Hi-Volt Resonant Controller RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓撲結(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel
L6599ADTR 功能描述:電壓模式 PWM 控制器 Hi-Volt resonant controller RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓撲結(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel
L6599AFD 功能描述:Power Supply Controller Resonant Converter Controller 16-SO 制造商:stmicroelectronics 系列:- 包裝:管件 零件狀態(tài):有效 應(yīng)用:諧振轉(zhuǎn)換器控制器 電壓 - 輸入:- 電壓 - 電源:8.85 V ~ 16 V 電流 - 電源:3.5mA 工作溫度:-50°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:16-SOIC(0.154",3.90mm 寬) 供應(yīng)商器件封裝:16-SO 標準包裝:50