- 您现在的位置：买卖IC网 > PDF目录20632 > LTC3670EDDB#TRMPBF (Linear Technology)IC REG TRPL BCK/LINEAR 12DFN PDF资料下载
参数资料
| 型号： | LTC3670EDDB#TRMPBF |
| 厂商： | Linear Technology |
| 文件页数： | 10/12页 |
| 文件大小： | 210K |
| 描述： | IC REG TRPL BCK/LINEAR 12DFN |
| 标准包装： | 500 |
| 拓扑： | 降压（降压）同步（1），线性（LDO）（2） |
| 功能： | 任何功能 |
| 输出数： | 3 |
| 频率 - 开关： | 2.25MHz |
| 电压/电流 - 输出 1： | 可调至0.8V，400mA |
| 电压/电流 - 输出 2： | 可调至0.8V，150mA |
| 电压/电流 - 输出 3： | 可调至0.8V，150mA |
| 带 LED 驱动器： | 无 |
| 带监控器： | 无 |
| 带序列发生器： | 无 |
| 电源电压： | 2.5 V ~ 5.5 V |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 12-WFDFN 裸露焊盘 |
| 供应商设备封装： | 12-DFN-EP（3x2） |
| 包装： | 带卷 (TR) |
| 其它名称： | LTC3670EDDB#PBF |
LTC3670
10
3670f
APPLICATIONS INFORMATION
Input/Output Capacitor Selection
Low ESR (equivalent series resistance) ceramic capacitors
should be used to bypass the following pins to ground:
V
IN
, the buck output, LDO1 and LDO2. Only X5R or X7R
ceramic capacitors should be used because they retain
their capacitance over wider voltage and temperature
ranges than other ceramic types. A 10糉 output capaci-
tor is suf cient for the buck regulator output. For good
transient response and stability the output capacitor for
the buck regulator should retain at least 4糉 of capacitance
over operating temperature and bias voltage. The V
IN
pin
should be bypassed with a 2.2糉 capacitor. The LDO1
and LDO2 output pins should each be bypassed with a
1糉 capacitor or greater. Larger values yield improved
transient response.
Consult with capacitor manufacturers for detailed infor-
mation and speci cations on their selection of ceramic
capacitors. Many manufacturers now offer very thin (<1mm
tall) ceramic capacitors ideal for use in height-restricted
designs. Table 2 shows a list of several ceramic capacitor
manufacturers.
Table 2. Ceramic Capacitor Manufacturers
AVX
www.avxcorp.com
Murata
www.murata.com
Taiyo Yuden
www.t-yuden.com
Vishay Siliconix
www.vishay.com
TDK
www.tdk.com
Output Voltage Programming
Figure 1 shows how feedback resistor dividers are con-
nected to the LTC3670 to set the output voltages of the
buck and an LDO.
The output voltage of the buck regulator is determined by
R1 and R2, following the equation:
V
R
R
V
OUTBUCK
( )
" .
= +
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
1
2
1
08
An LDOs output voltage is similarly determined by R3
and R4, following:
V
R
R
V
OUTLDO
( )
" .
= +
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
1
4
3
08
Typical values for R2 and R4 are in the range from 40k
to 1M.
For improved buck regulator transient response, the capaci-
tor C
FB
cancels the pole created by the feedback resistors
and the input capacitance of the BUCKFB pin. A variety of
capacitor sizes can be used for C
FB
, but a value of 10pF
is recommended for most applications. Experimentation
with capacitor sizes between 2pF and 22pF may yield
improved transient response.
Printed Circuit Board Layout Considerations
When laying out the printed circuit board, the following
list should be followed to ensure proper operation of the
LTC3670:
1) The Exposed Pad of the package should connect directly
to a large ground plane to minimize thermal and electri-
cal impedance.
2) The connection from the input supply pin (V
IN
) to its
decoupling capacitor should be kept as short as pos-
sible. The GND side of this capacitor should connect
directly to the ground plane of the part. The V
IN
capacitor
provides the AC current to the buck regulators power
MOSFETs and their drivers. It is especially important
to minimize PCB trace inductance from this capacitor
to the V
IN
and GND pins of the LTC3670.
3) The switching power trace connecting the SW pin to the
inductor should be kept as short as possible to reduce
radiated EMI and parasitic coupling.
4) The LDO output capacitors should be placed as close to
the IC as possible, and connected to the LDO outputs
and the GND pin as directly as possible.
LTC3670
SW
R2
R1
V
OUT(BUCK)
V
OUT(LDO)
3670 F01
C
FB
BUCKFB
LDO
LDO_FB
R4
R3
Figure 1. Setting the Output Voltages of the LTC3670
相关PDF资料 |
PDF描述 |
|---|---|
| RW2-1205D/H3/SMD | CONV DC/DC 2W 9-18VIN +/-05VOUT |
| GSC49DRAS-S734 | CONN EDGECARD 98POS .100 R/A SLD |
| VI-J6X-CX-F2 | CONVERTER MOD DC/DC 5.2V 75W |
| M7PXK-0910R | D-SUB CABLE - MMM09K/MC10M/X |
| GCM08DTKD | CONN EDGECARD 16POS DIP .156 SLD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC3672BEDC-1#TRMPBF | 功能描述:IC REG TRPL BCK/LINEAR 8-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压（降压）同步（3），线性（LDO）（2） 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:* |
| LTC3672BEDC-1#TRPBF | 功能描述:IC REG TRPL BCK/LINEAR 8-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压（降压）同步（3），线性（LDO）（2） 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:* |
| LTC3672BEDC-2#TRMPBF | 功能描述:IC REG TRPL BCK/LINEAR 8-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压（降压）同步（3），线性（LDO）（2） 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:* |
| LTC3672BEDC-2#TRPBF | 功能描述:IC REG TRPL BCK/LINEAR 8-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压（降压）同步（3），线性（LDO）（2） 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:* |
| LTC3675EUFF#PBF | 功能描述:IC PMIC PWR SUPPLYED DVR 44-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 电源管理 - 专用 系列:- 标准包装:1 系列:- 应用:手持/移动设备 电流 - 电源:- 电源电压:3 V ~ 5.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:14-WFDFN 裸露焊盘 供应商设备封装:14-LLP-EP（4x4） 包装:Digi-Reel® 配用:LP3905SD-30EV-ND - BOARD EVALUATION LP3905SD-30 其它名称:LP3905SD-30DKR |
发布紧急采购，3分钟左右您将得到回复。