- 您现在的位置：买卖IC网 > PDF目录69516 > TPS61170DRVTG4 (TEXAS INSTRUMENTS INC) 1.44 A SWITCHING REGULATOR, 1500 kHz SWITCHING FREQ-MAX, PDSO6 PDF资料下载
参数资料
| 型号： | TPS61170DRVTG4 |
| 厂商： | TEXAS INSTRUMENTS INC |
| 元件分类： | 稳压器 |
| 英文描述： | 1.44 A SWITCHING REGULATOR, 1500 kHz SWITCHING FREQ-MAX, PDSO6 |
| 封装： | 2 X 2 MM, GREEN, PLASTIC, SON-6 |
| 文件页数： | 8/29页 |
| 文件大小： | 689K |
| 代理商： | TPS61170DRVTG4 |
第1页第2页第3页第4页第5页第6页第7页当前第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页
D +
Vout * Vin
Vout
I
in_DC +
Vout
Iout
Vin
h
SLVS789C
– NOVEMBER 2007 – REVISED APRIL 2011
SWITCH DUTY CYCLE
The maximum switch duty cycle (D) of the TPS61170 is 90% (min). The duty cycle of a boost converter under
continuous conduction mode (CCM) is given by:
(5)
For a 5V to 12V application, the duty cycle is 58.3%, and for a 5V to 24V application, the duty cycle is 79.2%.
The duty cycle must be lower than the maximum specification of 90% in the application; otherwise, the output
voltage can not be regulated.
Once the PWM switch is turned on, the TPS61170 has minimum ON pulse width. This sets the limit of the
minimum duty cycle. When operating at low duty cycles, the TPS61170 enters pulse-skipping mode. In this
mode, the device turns the power switch off for several switching cycles to prevent the output voltage from rising
above regulation. This operation typically occurs in light load condition when the PWM operates in discontinuous
mode. See the Figure 12.
INDUCTOR SELECTION
The selection of the inductor affects steady state operation as well as transient behavior and loop stability. These
factors make it the most important component in power regulator design. There are three important inductor
specifications: inductor value, DC resistance (DCR) and saturation current. Considering inductor value alone is
not enough.
The inductance value of the inductor determines its ripple current. It is recommended that the peak-to-peak ripple
current given by Equation 3 be set to 30
–40% of the DC current. Inductance values shown in the Recommended
Operating Conditions (ROC) table are recommended for most applications. Inductor DC current can be
calculated as
(6)
Inductor values can have
±20% tolerance with no current bias. When the inductor current approaches saturation
level, its inductance can decrease 20% to 35% from the 0A value depending on how the inductor vendor defines
saturation current. Using an inductor with a smaller inductance value forces discontinuous PWM where the
inductor current ramps down to zero before the end of each switching cycle. This reduces the boost converter
’s
maximum output current, causes large input voltage ripple and reduces efficiency. In general, inductors with
large inductance and low DCR values provide much more output current and higher conversion efficiency.
Inductors with smaller inductance values can give better load transient response. For these reasons, a 10
μH to
22
μH inductance value range is recommended. Table 3 lists some recommended inductors for the TPS61170.
TPS61170 has built-in slope compensation to avoid sub-harmonic oscillation associated with current mode
control. If the inductor value is lower than 10
μH, the slope compensation may not be adequate, and the loop can
become unstable. Therefore, customers need to verify operation in their application if the inductor is different
from the recommended values.
Table 3. Recommended Inductors for TPS61170
L
DCR MAX
SATURATION CURRENT
SIZE
PART NUMBER
VENDOR
(
μH)
(m
)
(A)
(L
× W × H mm)
A915_Y-100M
10
90
1.3
5.2
×5.2×3.0
TOKO
VLCF5020T-100M1R1-1
10
237
1.1
5
×5×2.0
TDK
CDRH4D22/HP
10
144
1.2
5
×5×2.4
Sumida
LQH43PN100MR0
10
247
0.84
4.5
×3.2×2.0
Murata
SCHOTTKY DIODE SELECTION
The high switching frequency of the TPS61170 demands a high-speed rectifying switch for optimum efficiency.
Ensure that the diode
’s average and peak current rating exceeds the average output current and peak inductor
current. In addition, the diode
’s reverse breakdown voltage must exceed the switch FET rating voltage of 40V.
So, the ONSemi MBR0540 is recommended for TPS61170. However, Schottky diodes with lower rated voltages
can be used for lower output voltages to save the solution size and cost. For example, a converter providing a
12V output with 20V diode is a good choice.
16
Copyright
2007–2011, Texas Instruments Incorporated
相关PDF资料 |
PDF描述 |
|---|---|
| TPS61202DSCTG4 | 1.5 A BATTERY CHARGE CONTROLLER, 1650 kHz SWITCHING FREQ-MAX, PDSO10 |
| TPS61201DRCT | 1.5 A BATTERY CHARGE CONTROLLER, 1650 kHz SWITCHING FREQ-MAX, PDSO10 |
| TPS61200DRC | 1.5 A BATTERY CHARGE CONTROLLER, 1650 kHz SWITCHING FREQ-MAX, PDSO10 |
| TPS61200DRCRG4 | 1.5 A BATTERY CHARGE CONTROLLER, 1650 kHz SWITCHING FREQ-MAX, PDSO10 |
| TPS61200DRCT | 1.5 A BATTERY CHARGE CONTROLLER, 1650 kHz SWITCHING FREQ-MAX, PDSO10 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| TPS61170EVM-280 | 功能描述:电源管理IC开发工具 TPS61170EVM-280 Eval Mod RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V |
| TPS61170EVM-316 | 功能描述:电源管理IC开发工具 TPS61170EVM-316 Eval Mod RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V |
| TPS61170-Q1 | 制造商:TI 制造商全称:Texas Instruments 功能描述:1.2A High Voltage Boost Converter in 2x2mm2 QFN Package |
| TPS61170QDRVRQ1 | 功能描述:直流/直流开关调节器 AC 1.2A SWITCH,HIGH VLTG BOOST CONVERTER RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
| TPS61175 | 制造商:TI 制造商全称:Texas Instruments 功能描述:3-A High Voltage Boost Converter with Soft-start and Programmable Switching Frequency |
发布紧急采购，3分钟左右您将得到回复。