- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄377751 > LTC1517-3.3 (Linear Technology Corporation) Micropower, Regulated 3.3V Charge Pump in a 5-Pin SOT-23 Package(微功耗,穩(wěn)壓型,3.3V電荷泵DC/DC變換器(5腳SOT-23封裝)) PDF資料下載
參數(shù)資料
| 型號(hào)： | LTC1517-3.3 |
| 廠商： | Linear Technology Corporation |
| 英文描述： | Micropower, Regulated 3.3V Charge Pump in a 5-Pin SOT-23 Package(微功耗,穩(wěn)壓型,3.3V電荷泵DC/DC變換器(5腳SOT-23封裝)) |
| 中文描述： | 微功耗，3.3V的穩(wěn)壓電荷泵采用5引腳SOT - 23封裝（微功耗，穩(wěn)壓型，3.3電荷泵型DC / DC變換器（5腳的SOT - 23封裝）） |
| 文件頁數(shù)： | 5/8頁 |
| 文件大小： | 193K |
| 代理商： | LTC1517-3.3 |
5
LTC1517-3.3
APPLICATIO
S I
FOR
ATIO
U
Operation
The LTC1517-3.3 uses a switched-capacitor charge pump
to boost V
IN
to a 3.3V
±
4% regulated output. The part
achieves regulation by sensing the output voltage through
an internal resistor divider and enabling the charge pump
when the divided output droops below the comparator’s
lower trip point (set by V
REF
). When the charge pump is
enabled, a 2-phase nonoverlapping clock controls the
internal charge pump switches. Flying capacitor C1 is
charged to V
IN
on phase one of the clock. On phase two of
the clock, C1 is stacked in series with V
IN
and connected
to V
OUT
through an internal switch. This sequence of
charging and discharging the flying capacitor occurs at a
free running frequency of 700kHz (typ) and continues until
the divided output voltage reaches the upper trip point of
the comparator. Once the output is back in regulation, the
charge pump is disabled. This method of bursting the
charge pump on and off enables the LTC1517-3.3 to
achieve high efficiency at extremely low output loads.
W
U
U
Output Ripple
Normal LTC1517-3.3 operation produces voltage ripple
on the V
OUT
pin. Output voltage ripple is required for the
parts to regulate. Low frequency ripple exists due to the
hysteresis in the sense comparator and propagation de-
lays in the charge pump enable/disable circuits. High
frequency ripple is also present mainly from the ESR
(equivalent series resistance) in the output capacitor.
Typical output ripple with V
IN
= 2.5V under maximum load
is 75mV peak-to-peak with a low ESR 3.3
μ
F output capaci-
tor (minimum recommended C
OUT
). For applications
requiring V
IN
to exceed 3.3V or for applications requiring
less than 75mV of peak-to-peak ripple, a 6.8
μ
F to 10
μ
F
C
OUT
capacitor is recommended. Slight further decreases
in output ripple can be achieved by using C
OUT
capacitors
larger than 10
μ
F.
Short-Circuit/Thermal Protection
During short-circuit conditions, the LTC1517-3.3 will draw
between 20mA and 150mA from V
IN
, causing a rise in
junction temperature. On-chip thermal shutdown circuitry
disables the charge pump once the junction temperature
exceeds approximately 160
°
C. The charge pump is
reenabled once the junction temperature drops to approxi-
mately 145
°
C. The LTC1517-3.3 will cycle in and out of
thermal shutdown indefinitely without latchup or damage
until the V
OUT
short is removed.
Capacitor Selection
For best performance, it is recommended that low ESR
capacitors be used for both C
IN
and C
OUT
to reduce noise
and ripple. The C
IN
and C
OUT
capacitors should be either
ceramic or tantalum and should be 3.3
μ
F or greater.
Ceramic capacitors will provide the smallest size for a
given capacitance. If the input source impedance is very
low (< 0.5
), C
IN
may not be needed. Ceramic capacitors
are recommended for the flying capacitor C1 with values
of 0.1
μ
F or 0.22
μ
F. Smaller value flying capacitors may be
used in low I
OUT
applications.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LTC1518CS | 52Mbps Precision Delay RS485 Quad Line Receivers |
| LTC1519CS | 52Mbps Precision Delay RS485 Quad Line Receivers |
| LTC1518 | 52Mbps Precision Delay RS485 Quad Line Receivers |
| LTC1519 | 52Mbps Precision Delay RS485 Quad Line Receivers |
| LTC1530CS8 | Isolated Flyback Switching Regulator with 9V Output |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC1517CS5-3.3 | 制造商:Linear Technology 功能描述:Charge Pump STPUP 3.3V 15mA 5-Pin TSOT-23 |
| LTC1517CS5-3.3#TR | 功能描述:IC REG SWITCHED CAP 3.3V SOT23-5 RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開關(guān)穩(wěn)壓器 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:升壓（升壓） 輸出類型:可調(diào)式 輸出數(shù):1 輸出電壓:1.24 V ~ 30 V 輸入電壓:1.5 V ~ 12 V PWM 型:電流模式，混合 頻率 - 開關(guān):600kHz 電流 - 輸出:500mA 同步整流器:無 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:8-SOIC（0.154"，3.90mm 寬） 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:8-SOIC |
| LTC1517CS5-3.3#TRM | 功能描述:IC REG SWITCHED CAP 3.3V SOT23-5 RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開關(guān)穩(wěn)壓器 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:升壓（升壓） 輸出類型:可調(diào)式 輸出數(shù):1 輸出電壓:1.24 V ~ 30 V 輸入電壓:1.5 V ~ 12 V PWM 型:電流模式，混合 頻率 - 開關(guān):600kHz 電流 - 輸出:500mA 同步整流器:無 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:8-SOIC（0.154"，3.90mm 寬） 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:8-SOIC |
| LTC1517CS5-3.3#TRMPBF | 功能描述:IC REG SWITCHED CAP 3.3V SOT23-5 RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開關(guān)穩(wěn)壓器 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:升壓（升壓） 輸出類型:可調(diào)式 輸出數(shù):1 輸出電壓:1.24 V ~ 30 V 輸入電壓:1.5 V ~ 12 V PWM 型:電流模式，混合 頻率 - 開關(guān):600kHz 電流 - 輸出:500mA 同步整流器:無 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:8-SOIC（0.154"，3.90mm 寬） 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:8-SOIC |
| LTC1517CS5-3.3#TRPBF | 功能描述:IC REG SWITCHED CAP 3.3V SOT23-5 RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開關(guān)穩(wěn)壓器 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:升壓（升壓） 輸出類型:可調(diào)式 輸出數(shù):1 輸出電壓:1.24 V ~ 30 V 輸入電壓:1.5 V ~ 12 V PWM 型:電流模式，混合 頻率 - 開關(guān):600kHz 電流 - 輸出:500mA 同步整流器:無 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:8-SOIC（0.154"，3.90mm 寬） 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:8-SOIC |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。