參數(shù)資料
型號(hào)： LTC3737EUF
廠商： LINEAR TECHNOLOGY CORP
元件分類： 穩(wěn)壓器
英文描述： Dual 2-Phase, No RSENSE DC/DC Controller with Output Tracking
中文描述： 1 A DUAL SWITCHING CONTROLLER, 825 kHz SWITCHING FREQ-MAX, PQCC24
封裝： 4 X 4 MM, PLASTIC, QFN-24
文件頁(yè)數(shù)： 11/28頁(yè)
文件大?。?/td> 372K
代理商： LTC3737EUF
11
LTC3808
3808f
A phase-locked loop (PLL) is available on the LTC3808 to
synchronize the internal oscillator to an external clock
source that connects to the SYNC/MODE pin. In this case,
a series RC should be connected between the PLLLPF pin
and GND to serve as the PLL’s loop filter. The LTC3808
phase detector adjusts the voltage on the PLLLPF pin to
align the turn-on of the external P-channel MOSFET to the
rising edge of the synchronizing signal.
The typical capture range of the LTC3808’s phase-locked
loop is from approximately 200kHz to 1MHz.
Spread Spectrum Modulation (SYNC/MODE and
PLLLPF Pins)
Connecting the SYNC/MODE pin to a DC voltage above
1.35V and several hundred mV below V
IN
enables spread
spectrum modulation (SSM) operation. An internal 2.6
μ
A
pull-down current source at SYNC/MODE helps to set the
voltage at the SYNC/MODE pin for this operation by tying
a resistor with appropriate value between SYNC/MODE
and V
IN
. This mode of operation spreads the internal
oscillator frequency f
OSC
(= 550kHz) over a wider range
(460kHz to 635kHz), reducing the peaks of the harmonic
output on a spectral analysis of the output noise. In this
case, a 2.2nF filter cap should be connected between the
PLLLPF pin and GND and another 1000pF cap should be
connected between PLLLPF and the SYNC/MODE pin. The
controller operates in PWM pulse skipping mode at light
loads when spread spectrum modulation is selected. See
more discussions in the Spread Spectrum Modulation
with SYNC/MODE and PLLLPF Pins in the Applications
Information section.
Dropout Operation
When the input supply voltage (V
IN
) approaches the
output voltage, the rate of change of the inductor current
while the external P-channel MOSFET is on
(ON cycle) decreases. This reduction means that the
P-channel MOSFET will remain on for more than one
oscillator cycle if the inductor current has not ramped up
to the threshold set by the EAMP on the I
TH
pin. Further
reduction in the input supply voltage will eventually cause
the P-channel MOSFET to be turned on 100%; i.e., DC.
The output voltage will then be determined by the input
voltage minus the voltage drop across the P-channel
MOSFET and the inductor.
Undervoltage Lockout
To prevent operation of the P-channel MOSFET below
safe input voltage levels, an undervoltage lockout is
incorporated in the LTC3808. When the input supply
voltage (V
IN
) drops below 2.25V, the external P- and
N-channel MOSFETs and all internal circuits are turned
off except for the undervoltage block, which draws only
a few microamperes.
Peak Current Sense Voltage Selection and Slope
Compensation (IPRG Pin)
When the LTC3808 controller is operating below 20% duty
cycle, the peak current sense voltage (between the SENSE
+
and SENSE
–
/SW pins) allowed across the external P-
channel MOSFET is determined by:
=
V
A
V
V
SENSE MAX
ITH
(
)
– .7
10
where A is a constant determined by the state of the IPRG
pin. Floating the IPRG pin selects A = 1; tying IPRG to V
IN
selects A = 5/3; tying IPRG to GND selects A = 2/3. The
OPERATIOU
(Refer to Functional Diagram)
相關(guān)PDF資料
PDF描述
LTC3808EDE No RSENSE Low EMI, Synchronous DC/DC Controller with Output Tracking
LTC3713 Low Input Voltage, High Power, No RSENSE Synchronous Buck DC/DC Controller
LTC3713EG Low Input Voltage, High Power, No RSENSE Synchronous Buck DC/DC Controller
LTC3714 Intel Compatible, Wide Operating Range, Step-Down Controller with Internal Op Amp
LTC3714EG Intel Compatible, Wide Operating Range, Step-Down Controller with Internal Op Amp
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LTC3737EUF#PBF 功能描述:IC REG CTRLR BUCK PWM CM 24-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:PolyPhase® 標(biāo)準(zhǔn)包裝:2,500 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:500kHz 占空比:96% 電源電壓:4 V ~ 36 V 降壓:無(wú) 升壓:是 回掃:無(wú) 反相:無(wú) 倍增器:無(wú) 除法器:無(wú) Cuk:無(wú) 隔離:無(wú) 工作溫度:-40°C ~ 125°C 封裝/外殼:24-WQFN 裸露焊盤 包裝:帶卷 (TR)
LTC3737EUF#TR 功能描述:IC REG CTRLR BUCK PWM CM 24-QFN RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:PolyPhase® 標(biāo)準(zhǔn)包裝:2,500 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:500kHz 占空比:96% 電源電壓:4 V ~ 36 V 降壓:無(wú) 升壓:是 回掃:無(wú) 反相:無(wú) 倍增器:無(wú) 除法器:無(wú) Cuk:無(wú) 隔離:無(wú) 工作溫度:-40°C ~ 125°C 封裝/外殼:24-WQFN 裸露焊盤 包裝:帶卷 (TR)
LTC3737EUF#TRPBF 功能描述:IC REG CTRLR BUCK PWM CM 24-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:PolyPhase® 標(biāo)準(zhǔn)包裝:2,500 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:500kHz 占空比:96% 電源電壓:4 V ~ 36 V 降壓:無(wú) 升壓:是 回掃:無(wú) 反相:無(wú) 倍增器:無(wú) 除法器:無(wú) Cuk:無(wú) 隔離:無(wú) 工作溫度:-40°C ~ 125°C 封裝/外殼:24-WQFN 裸露焊盤 包裝:帶卷 (TR)
LTC3738CUHF 功能描述:IC CTRLR SW REG 3PH STPDWN 38QFN RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標(biāo)準(zhǔn)包裝:43 系列:- 應(yīng)用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:48-QFN（7x7） 包裝:管件
LTC3738CUHF#PBF 功能描述:IC CTRLR SW REG 3PH STPDWN 38QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標(biāo)準(zhǔn)包裝:43 系列:- 應(yīng)用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:48-QFN（7x7） 包裝:管件
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

*
*
*