参数资料
型号: TPS65140PWPR
厂商: TEXAS INSTRUMENTS INC
元件分类: 稳压器
英文描述: 2.6 A SWITCHING REGULATOR, 2100 kHz SWITCHING FREQ-MAX, PDSO24
封装: GREEN, PLASTIC, HTSSOP-24
文件页数: 10/31页
文件大小: 1391K
代理商: TPS65140PWPR
www.ti.com
V
= -V
x
OUT
REF
= -1.213 V x
R
3
R
4
R3 = R4 x
= R4 x
|VOUT|
VREF
1.213
SLVS497C – SEPTEMBER 2003 – REVISED APRIL 2006
Figure 22. Optimum, RC Is Ideal
Negative Charge Pump
The negative charge pump provides a regulated output voltage by inverting the main output voltage, VO1. The
negative charge pump output voltage is set with external feedback resistors.
The maximum load current of the negative charge pump depends on the voltage drop across the external
Schottky diodes, the internal on resistance of the charge pump MOSFETS Q8 and Q9, and the impedance of
the flying capacitor, C12. When the voltage drop across these components is larger than the voltage difference
from VO1 to VO2, the charge pump is in drop out, providing the maximum possible output current. Therefore, the
higher the voltage difference between VO1 and VO2, the higher the possible load current. See Figure 12 for the
possible output current versus boost converter voltage VO1 and the calculations below.
Vout
min = -(VO1 - 2 VD - IO (2 x rDS(on)Q8 + 2 x rDS(on)Q9 + Xcfly))
Setting the output voltage:
The lower feedback resistor value, R4, should be in a range between 40 k
to 120 k or the overall feedback
resistance should be within 500 k
to 1 M. Smaller values load the reference too heavy and larger values may
cause stability problems. The negative charge pump requires two external Schottky diodes. The peak current
rating of the Schottky diode has to be twice the load current of the output. For a 20 mA output current, the dual
Schottky diode BAT54 or similar is a good choice.
Positive Charge Pump
The positive charge pump can be operated in a voltage doubler mode or a voltage tripler mode depending on
the configuration of the C2+ and C2-/MODE pins. Leaving the C2+ pin open and connecting C2-/MODE to GND
forces the positive charge pump to operate in a voltage doubler mode. If higher output voltages are required the
positive charge pump can be operated as a voltage tripler. To operate the charge pump in the voltage tripler
mode, a flying capacitor needs to be connected to C2+ and C2-/MODE.
The maximum load current of the positive charge pump depends on the voltage drop across the internal
Schottky diodes, the internal on-resistance of the charge pump MOSFETS, and the impedance of the flying
capacitor. When the voltage drop across these components is larger than the voltage difference VO1 x 2 to VO3
(doubler mode) or VO1 x 3 to VO3 (tripler mode), then the charge pump is in dropout, providing the maximum
possible output current. Therefore, the higher the voltage difference between VO1 x 2 (doubler) or VO1 x 3
(tripler) to VO3, the higher the possible load current. See Figure 13 and Figure 14 for output current versus boost
converter voltage, VO1, and the following calculations.
Voltage doubler:
VO3max = 2 x VO1 - (2 VD + 2 x IO x (2 x rDS(on)Q5 + rDS(on)Q3 + rDS(on)Q4 + XC1))
Voltage tripler:
VO3max = 3 x VO - (3 x VD + 2 x IO x (3 x rDS(on)Q5 + rDS(on)Q3 + rDS(on)Q4 + XC1 + XC2))
18
相关PDF资料
PDF描述
TPS65140PWPG4 2.6 A SWITCHING REGULATOR, 2100 kHz SWITCHING FREQ-MAX, PDSO24
TPS65160PWPG4 4.2 A SWITCHING REGULATOR, 900 kHz SWITCHING FREQ-MAX, PDSO28
TPS65160PWPR 4.2 A SWITCHING REGULATOR, 900 kHz SWITCHING FREQ-MAX, PDSO28
TPS65163RGZR 4.2 A SWITCHING REGULATOR, 900 kHz SWITCHING FREQ-MAX, PQCC48
TPS65185RGZR 1-CHANNEL POWER SUPPLY SUPPORT CKT, PQCC48
相关代理商/技术参数
参数描述
TPS65140PWPRG4 功能描述:LCD 驱动器 Trp-Ch 2.1-A Swit Boost Converter RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube
TPS65140RGER 功能描述:LCD 驱动器 Trp-Ch 2.1-A Swit Boost Converter RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube
TPS65140RGERG4 功能描述:LCD 驱动器 Trp-Ch 2.1-A Swit Boost Converter RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube
TPS65141PWP 功能描述:LCD 驱动器 5V/1.6A(I/O) 4-CH Multi-Converter RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube
TPS65141PWPG4 功能描述:LCD 驱动器 5V/1.6A(I/O) 4-CH Multi-Converter RoHS:否 制造商:Maxim Integrated 数位数量:4.5 片段数量:30 最大时钟频率:19 KHz 工作电源电压:3 V to 3.6 V 最大工作温度:+ 85 C 最小工作温度:- 20 C 封装 / 箱体:PDIP-40 封装:Tube