- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄69003 > L6722TR (STMICROELECTRONICS) SWITCHING CONTROLLER, 300 kHz SWITCHING FREQ-MAX, QCC36 PDF資料下載
參數(shù)資料
| 型號(hào)： | L6722TR |
| 廠商： | STMICROELECTRONICS |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | SWITCHING CONTROLLER, 300 kHz SWITCHING FREQ-MAX, QCC36 |
| 封裝： | 6 X 6 MM, 1 MM PITCH, VFQFPN-36 |
| 文件頁數(shù)： | 17/34頁 |
| 文件大?。?/td> | 421K |
| 代理商： | L6722TR |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁當(dāng)前第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁
Obsolete
Product(s)
- Obsolete
Product(s)
9 Output voltage monitor and protections
L6722
24/34
9.5
PGOOD
It is an open-drain signal set free after the soft-start sequence has finished. It is pulled low
when the output voltage drops below -150mV of the programmed voltage.
9.6
Over-current protection
The Over Current threshold has to be programmed, by designing the RISENx resistors, to a safe
value, in order to be sure that the device doesn't enter OCP during normal operations. This
value must take into consideration also the process spread and temperature variations of the
sensing elements as well as the minimum value IOCTH(min) of the threshold as follow:
where IOCPx is the current measured by the current reading circuitry when the device enters
Quasi-Constant-Current.
Since the device reads the current across Low Side mosfets, it limits the bottom of the inductor
current entering in constant current until setting UVP as below explained. IOCPx must be
calculated starting from the corresponding output current value IOUT(OCP) as follow since the
device holds the valley current information:
where IOUT(OCP) is still the output current value at which the device enters Quasi-Constant-
Current, and IPP is the inductor current ripple in each phase. In particular, since the device
limits the valley of the inductor current, the ripple entity, when not negligible, impacts on the real
OC threshold value and must be considered.
The device detects an Over Current condition for each phase when the current information
IISENx overcomes the fixed threshold of IOCTH. When this happens, the device keeps the
relative LS mosfet on, also skipping clock cycles, until the threshold is crossed back and IISENx
results being lower than the IOCTH threshold (this implies that the device limits the bottom of
each inductor current ripple). After exiting the OC condition, the LS mosfet is turned off and the
HS is turned on with a duty cycle driven by the PWM comparator.
Keeping the LS on, skipping clock cycles, causes the on-time subsequent to the exit from the
OC condition, driven by the control loop, to increase. The device enters in Quasi-Constant-
Current operation: the low-side mosfets stays ON until the current read becomes lower than
IOCPx (IINFOx < IOCTH) skipping clock cycles. The high side mosfet can be then turned ON with
a TON imposed by the control loop after the LS turn-off and the device works in the usual way
until another OCP event is detected.
This means that the average current delivered can slightly increase in Quasi-Constant-Current
operation since the current ripple increases. In fact, the ON time increases due to the OFF time
rise because of the current has to reach the IOCPx bottom. The worst-case condition is when
the ON time reaches its maximum value.
When this happens, the device works in Real Constant Current and the output voltage
decrease as the load increase. Crossing the UVP threshold causes the device to latch driving
high the OSC pin.
It can be observed that the peak current (IPEAK) is greater than IOCPx but it can be determined
as follow:
Rg
I
OCPx max
()
R
dsON max
()
I
OCTH min
()
---------------------------------------------------------------------
=
I
OCPx
I
OUT OCP
()
3
----------------------------
I
PP
2
------------
–
=
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| L9407F | SPECIALTY ANALOG CIRCUIT, PSFM8 |
| L9942 | STEPPER MOTOR CONTROLLER, PDSO36 |
| LA5681FN | SWITCHING CONTROLLER, 520 kHz SWITCHING FREQ-MAX, QCC48 |
| LB11620T | BRUSHLESS DC MOTOR CONTROLLER, 0.25 A, PDSO24 |
| LB11875 | BRUSHLESS DC MOTOR CONTROLLER, 0.03 A, PDSO36 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| L6725 | 功能描述:開關(guān)變換器、穩(wěn)壓器與控制器 Vltg Mode PWM Controller RoHS:否 制造商:Texas Instruments 輸出電壓:1.2 V to 10 V 輸出電流:300 mA 輸出功率: 輸入電壓:3 V to 17 V 開關(guān)頻率:1 MHz 工作溫度范圍: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:WSON-8 封裝:Reel |
| L6725_07 | 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Voltage mode PWM controller with bootstrap anti-discharging system |
| L6725A | 功能描述:開關(guān)變換器、穩(wěn)壓器與控制器 Vltg Mode PWM Controller RoHS:否 制造商:Texas Instruments 輸出電壓:1.2 V to 10 V 輸出電流:300 mA 輸出功率: 輸入電壓:3 V to 17 V 開關(guān)頻率:1 MHz 工作溫度范圍: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:WSON-8 封裝:Reel |
| L6725ATR | 功能描述:開關(guān)變換器、穩(wěn)壓器與控制器 Step-Down Controller RoHS:否 制造商:Texas Instruments 輸出電壓:1.2 V to 10 V 輸出電流:300 mA 輸出功率: 輸入電壓:3 V to 17 V 開關(guān)頻率:1 MHz 工作溫度范圍: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:WSON-8 封裝:Reel |
| L6725TR | 功能描述:電壓模式 PWM 控制器 Adjustable Step Down Controller RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(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 |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。