- 您現(xiàn)在的位置：買賣IC網(wǎng) > Datasheet目錄41 > LTC3104IMSE#TRPBF (Linear Technology)IC REG DL BCK/LINEAR SYNC 16MSOP Datasheet資料下載
參數(shù)資料
| 型號(hào)： | LTC3104IMSE#TRPBF |
| 廠商： | Linear Technology |
| 文件頁數(shù)： | 14/20頁 |
| 文件大小： | 339K |
| 描述： | IC REG DL BCK/LINEAR SYNC 16MSOP |
| 標(biāo)準(zhǔn)包裝： | 2,500 |
| 拓?fù)洌?/td> | 降壓（降壓）同步（1），線性（LDO）（1） |
| 功能： | 任何功能 |
| 輸出數(shù)： | 2 |
| 頻率 - 開關(guān)： | 1.2MHz |
| 電壓/電流 - 輸出 1： | 0.6 V ~ 13.8 V，300mA |
| 電壓/電流 - 輸出 2： | 0.6 V ~ 14.5 V，10mA |
| 帶 LED 驅(qū)動(dòng)器： | 無 |
| 帶監(jiān)控器： | 無 |
| 帶序列發(fā)生器： | 無 |
| 電源電壓： | 2.5 V ~ 15 V |
| 工作溫度： | -40°C ~ 125°C |
| 安裝類型： | 表面貼裝 |
| 封裝/外殼： | 16-TFSOP（0.118"，3.00mm 寬）裸露焊盤 |
| 供應(yīng)商設(shè)備封裝： | 16-MSOP，裸露焊盤 |
| 包裝： | 帶卷 (TR) |
LTC3104
14
3104f
Input Capacitor Selection
The V
IN
and V
INLDO
pins provide current to the power
stages of the buck converter and the LDO, respectively.
It is recommended that a low ESR ceramic capacitor with
a value of at least 10礔 be used to bypass each of these
pins. These capacitors should be placed as close to the
respective pin as possible and should have a short return
path to the GND pin.
Output Voltage Programming
The output voltage is set by a resistive divider according
to the following formula:
V
OUT
=0.6V 1+
R2
R1
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
The external divider is connected to the output as shown
in Figure 1. Note that FB divider current is not included in
the LTC3104 quiescent current specification. For improved
transient response, a feedforward capacitor, C
FF
, may be
placed in parallel with resistor R2. The capacitor modifies
the loop dynamics by adding a pole-zero pair to the loop
dynamics which generates a phase boost that can improve
the phase margin and increase the speed of the transient
response, resulting in smaller voltage deviation on load
transients. The zero frequency depends not only on the
value of the feed forward capacitor, but also on the upper
resistor divider resistor. Specifically, the zero frequency,
f
ZERO
, is given by the following equation:
f
ZERO
=
1
2 ?R2 C
FF1
For R2 resistor values of ~1M a 12pF ceramic capacitor
will suffice, however that value may be increased or de-
creased to optimize the converters response for a given
set of application parameters.
APPLICATIONS INFORMATION
Figure 1. Setting the Output Voltage
FB
R2
R1
C
FF1
3104 F01
V
OUT
GND
LTC3104
Minimum Off-Time/On-Time Considerations
The maximum duty cycle is limited in the LTC3104 by the
boost capacitor refresh time, the rise/fall times of the switch
as well as propagation delays in the PWM comparator, the
level shifts and the gate drive. This minimum off-time is
typically 65ns which imposes a maximum duty cycle of:
DC
MAX
= 1 (f " t
OFF(MIN)
)
where f is the 1.2MHz switching frequency and t
OFF(MIN)
is the minimum off-time. If the maximum duty cycle is
surpassed, due to a dropping input voltage for example,
the output will drop out of regulation. The minimum input
voltage to avoid this dropout condition is:
V
IN(MIN)
=
V
OUT
1 f t
OFF(MIN)
(
)
Conversely, the minimum on-time is the smallest duration
of time in which the buck switch can be in its on state.
This time is limited by similar factors and is typically 70ns.
In forced continuous operation, the minimum on-time limit
imposes a minimum duty cycle of:
DC
MIN
= f " t
ON(MIN)
where t
ON(MIN)
is the minimum on-time. In extreme step-
down ratios where the minimum duty cycle is surpassed,
the output voltage will still be in regulation but the rectifier
switch will remain on for more than one cycle and sub-
harmonic switching will occur to provide a higher effective
duty cycle. The result is higher output voltage ripple. This is
an acceptable result in many applications so this constraint
may not be of critical importance in some cases.
Precise Undervoltage Lockout
The LTC3104 is in shutdown when the RUN pin is low and
active when the pin is higher than the RUN pin threshold.
The rising threshold of the RUN pin comparator is an
accurate 0.8V, with 60mV of hysteresis. This threshold is
enabled when V
IN
is above the 2.5V minimum value. If V
IN
is lower than 2.5V, an internal undervoltage monitor puts
the part in shutdown independent of the RUN pin state.
The RUN pin can be configured as a precise undervoltage
lockout (UVLO) on the V
IN
supply with a resistive divider
tied to the RUN pin as shown in Figure 2 to meet specific
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LTC3445EUF#TRPBF | IC REG TRPL BUCK/LINEAR 24-QFN |
| LTC3446IDE#PBF | IC REG TRPL BCK/LINEAR 14-DFN |
| LTC3537EUD#TRPBF | IC REG DL BST/LINEAR SYNC 16-QFN |
| LTC3541EDD#TRPBF | IC REG DL BCK/LINEAR SYNC 10-DFN |
| LTC3670EDDB#TRPBF | IC REG TRPL BCK/LINEAR 12DFN |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC3105 | 制造商:LINER 制造商全稱:Linear Technology 功能描述:400mA Step-Up DC/DC Converter with Maximum Power Point Control and 250mV Start-Up |
| LTC3105EDD#PBF | 功能描述:IC CONV DC/DC 400MA HIEFF 10-DFN 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 |
| LTC3105EDD#TRPBF | 功能描述:IC CONV DC/DC 400MA HIEFF 10-DFN 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 |
| LTC3105EMS#PBF | 功能描述:IC CONV DC/DC STEP DOWN 12-MSOP 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:2,000 系列:- 應(yīng)用:控制器，DSP 輸入電壓:4.5 V ~ 25 V 輸出數(shù):2 輸出電壓:最低可調(diào)至 1.2V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:30-TFSOP（0.173"，4.40mm 寬） 供應(yīng)商設(shè)備封裝:30-TSSOP 包裝:帶卷 (TR) |
| LTC3105EMS#TRPBF | 功能描述:IC CONV DC/DC 400MA HIEFF 12MSOP 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)。