- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄377774 > LTC3216EDE (LINEAR TECHNOLOGY CORP) 1A Low Noise High Current LED Charge Pump with Independent Torch/Flash Current Control PDF資料下載
參數(shù)資料
| 型號(hào)： | LTC3216EDE |
| 廠商： | LINEAR TECHNOLOGY CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | 1A Low Noise High Current LED Charge Pump with Independent Torch/Flash Current Control |
| 中文描述： | 1.5 A SWITCHED CAPACITOR REGULATOR, PDSO12 |
| 封裝： | 3 X 4 MM, PLASTIC, MO-229-WGED, DFN-12 |
| 文件頁數(shù)： | 6/12頁 |
| 文件大小： | 102K |
| 代理商： | LTC3216EDE |
LTC 3216
6
3216fa
The LTC3216 uses a fractional switched capacitor charge
pump to power a high current LED with a programmed
regulated current. The part starts up into the 1x mode. In
this mode, V
IN
is directly connected to CPO. This mode
provides maximum efficiency and minimum noise. The
LTC3216 will remain in this mode until the LED current
source begins to dropout. When dropout is detected, the
LTC3216 will switch to 1.5x mode after a soft-start period.
Any subsequent dropout detected will cause the part to
enter 2x mode. The part may be reset to 1x mode by
bringing the part into shutdown mode and then reenabling
the part.
A two phase nonoverlapping clock activates the charge
pump switches. In the 2x mode, the flying capacitors are
charged on alternate clock phases from V
IN
. While one
capacitor is being charged from V
IN
, the other is stacked
on top of V
IN
and connected to the output. Alternatively, in
the 1.5x mode the flying capacitors are charged in series
during the first clock phase, and stacked in parallel on top
of V
IN
on the second clock phase. This sequence of
charging and discharging the flying capacitors continues
at a free running frequency of 900kHz (typ).
The current delivered to the LED load is controlled by the
internal programmable current source. Three discrete
current settings (Low, High and Low + High) are available
and may be selected via the EN2 and EN1 pins. The values
of these currents may be selected by choosing the appro-
priate programming resistors. Each resistor is connected
between the I
SET2
or I
SET1
pin and GND. The resistor
values needed to attain the desired current levels can be
determined by equation 1.
R
SET1/2
= 3965/I
LED
A resistor value of 2k
or less (i.e. a short-circuit) will
cause the LTC3216 to enter overcurrent shutdown mode.
This mode will prevent damage to the part by shutting
down the high power sections of the chip.
(1)
Regulation is achieved by sensing the voltage at the CPO
pin and modulating the charge pump strength based on
the error signal. The CPO regulation voltages are set
internally, and are dependent on the charge pump mode as
shown in Table 1.
Table 1. Charge Pump Output Regulation Voltages
Charge Pump Mode
1.5x
2x
V
CPO
4.6V
5.1V
In shutdown mode all circuitry is turned off and the
LTC3216 draws a very low current from the V
IN
supply.
Furthermore, CPO is weakly connected to V
IN
. The LTC3216
enters shutdown mode when both the EN1 and EN2 pins
are brought low. Since EN1 and EN2 are high impedance
CMOS inputs they should never be allowed to float. To
ensure that their states are defined they must always be
driven with valid logic levels.
Thermal Protection
The LTC3216 has built-in overtemperature protection.
Thermal shutdown circuitry will shutdown the I
LED
output
when the junction temperature exceeds approximately
150
°
C. It will re-enable the I
LED
output once the junction
temperature drops back to approximately 135
°
C. The
LTC3216 will cycle in and out of thermal shutdown indefi-
nitely without latch up or damage until the heat source is
removed.
Soft-Start
To prevent excessive inrush current during start-up and
mode switching, the LTC3216 employs built-in soft-start
circuitry. Soft-start is achieved by increasing the amount
of current available to the output charge storage capacitor
linearly over a period of approximately 250
μ
s.
Charge Pump Strength
When the LTC3216 operates in either the 1.5x mode or 2x
mode, the charge pump can be modeled as a Thevenin-
equivalent circuit to determine the amount of current
available from the effective input voltage and effective
open-loop output resistance, R
OL
(Figure 1).
OPERATIOU
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LT3467 | 1A Low Noise High Current LED Charge Pump with Independent Torch/Flash Current Control |
| LT3467A | 1A Low Noise High Current LED Charge Pump with Independent Torch/Flash Current Control |
| LTC3216 | Single Cell 350mA LED Driver |
| LTC3400ES6 | 600mA, 1.2MHz Micropower Synchronous Boost Converter in ThinSOT |
| LTC3400 | 600mA, 1.2MHz Micropower Synchronous Boost Converter in ThinSOT |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC3216EDE#PBF | 功能描述:IC CHARGE PUMP LED 12-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 |
| LTC3216EDE#TRPBF | 功能描述:IC CHARGE PUMP LED 12-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 |
| LTC3217 | 制造商:LINER 制造商全稱:Linear Technology 功能描述:600mA Low Noise Multi-LED Camera Light Charge Pump |
| LTC3217EUD | 制造商:Linear Technology 功能描述:LED DRVR 4Segment 3.3V 16-Pin QFN EP |
| LTC3217EUD#PBF | 功能描述:IC LED DRVR FLASH TORCH 16QFN RoHS:是 類別:集成電路 (IC) >> PMIC - LED 驅(qū)動(dòng)器 系列:- 標(biāo)準(zhǔn)包裝:6,000 系列:- 恒定電流:- 恒定電壓:- 拓?fù)?開路漏極，PWM 輸出數(shù):4 內(nèi)部驅(qū)動(dòng)器:是 類型 - 主要:LED 閃爍器 類型 - 次要:- 頻率:400kHz 電源電壓:2.3 V ~ 5.5 V 輸出電壓:- 安裝類型:表面貼裝 封裝/外殼:8-VFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:8-HVSON 包裝:帶卷 (TR) 工作溫度:-40°C ~ 85°C 其它名稱:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。