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PT6671E 参数 Datasheet PDF下载

PT6671E图片预览
型号: PT6671E
PDF下载: 下载PDF文件 查看货源
内容描述: SMPS控制器\n [SMPS Controller ]
分类和应用: 稳压器开关式稳压器或控制器电源电路开关式控制器
文件页数/大小: 5 页 / 114 K
品牌: TI [ TEXAS INSTRUMENTS ]
 浏览型号PT6671E的Datasheet PDF文件第1页浏览型号PT6671E的Datasheet PDF文件第2页浏览型号PT6671E的Datasheet PDF文件第4页浏览型号PT6671E的Datasheet PDF文件第5页  
Application Notes  
PT6670 Series  
Figure 1  
Adjusting the Output Voltage of the PT6670  
Series Boost Voltage ISR  
1
The Power Trends PT6670 ISRs are a series of convert-  
ers that operate from a 3.3V or 5V input bus voltage. In  
each case, the output voltage can be adjusted higher or  
lower than the factory trimmed pre-set voltage. Adjust-  
ment requires the addition of a single external resistor.  
Table 1 gives the permissible adjustment range for each  
model in the series as Va(min) and Va(max) respectively.  
Vsense  
4,5,6  
11,12,13  
Vin  
Vo  
Vin  
PT6670  
Vo  
GND  
Vo(adj)  
14  
7,8,9,10  
(R1)  
Adj Down  
L
O
A
D
+
+
Cin  
Cout  
R 2  
Adjust Up:  
To increase the output, add a resistor  
Adjust  
U p  
R2 between pin 14 (Vo Adjust) and pins 7-10 (GND).  
Adjust Down: Add a resistor (R1), between pin 14  
C O M  
C O M  
(Vo Adjust) and pin 1 (Remote Sense).  
Table 1  
Refer to Figure 1 and Table 2 for both the placement and value  
of the required resistor.  
PT6670 ADJUSTMENT RANGE AND FORMULA PARAMETERS  
Series Pt #  
3.3V Bus  
5.0V Bus  
PT6671  
PT6672  
PT6675  
PT6673  
PT6674  
Notes:  
1. Use only a single 1% resistor in either the (R1) or R2  
location. Place the resistor as close to the ISR as possible.  
2. Do not exceed the maximum advised adjustment voltage.  
Doing so could over stress the part.  
3. Never connect capacitors to the Vo Adjust control pin. Any  
capacitance added to this pin will affect the stability of the  
ISR.  
V (nom)  
o
5.0V  
3.8V  
5.5V  
25.0  
9.0V  
8.2V  
9.2V  
48.75  
80.6  
12.0V  
9.6V  
Va(min)  
Va(max)  
12.8V  
47.41  
54.9  
K
(V·k)  
(k)  
o
R
s
4.99  
Table 2  
4. In the case of the PT6671, when the output is adjusted  
lower than the pre-trimmed output, the maximum input  
voltage to the ISR should not exceed (V0 – 0.5)V.  
PT6670 ADJUSTMENT RESISTOR VALUES  
Series Pt #  
3.3V Bus  
5.0V Bus  
PT6671  
PT6672  
PT6675  
PT6673  
PT6674  
The adjust up and adjust down resistor values can also be  
calculated using the following formulas. Be sure to select  
the correct formula parameters from Table 1 for the model  
being adjusted.  
V (nom)  
o
5.0V  
9.0V  
12.0V  
Va(req’d)  
3.8  
Va(req’d)  
8.2  
(5.8)kΩ  
(7.7)kΩ  
(58.3)kΩ  
(111.0)kΩ  
(217.0)kΩ  
(534.0)kΩ  
3.9  
8.4  
4.0  
(10.0kΩ  
8.6  
Ko (Va – 2.5)  
2.5 (Vo – Va)  
4.1  
(12.8)kΩ  
(16.3)kΩ  
(20.7)kΩ  
(26.7)kΩ  
(35.0)kΩ  
(47.5)kΩ  
(68.3)kΩ  
(110.0)kΩ  
(235.0)kΩ  
8.8  
(R1)  
=
– Rs kΩ  
4.2  
9.0  
4.3  
9.2  
163.0kΩ  
4.4  
9.4  
Ko  
Va – Vo  
4.5  
9.6  
(1.2)kΩ  
(8.0)kΩ  
R2  
=
– Rs kΩ  
4.6  
9.8  
4.7  
10.0  
10.2  
10.4  
10.6  
10.8  
11.0  
11.2  
11.4  
11.6  
11.8  
12.0  
12.2  
12.4  
12.6  
12.8  
(16.2)kΩ  
(26.2)kΩ  
(38.7)kΩ  
(54.8)kΩ  
(76.3)kΩ  
(106.0)kΩ  
(151.0)kΩ  
(226.0)kΩ  
(376.0)kΩ  
(827.0)kΩ  
4.8  
4.9  
Where:  
Vo = Original output voltage  
Va = Adjusted output voltage  
5.0  
5.1  
245.0kΩ  
120.0kΩ  
78.3kΩ  
57.5kΩ  
45.0kΩ  
Ko = The multiplier constant in Table 1  
Rs = The series resistance from Table 1  
5.2  
5.3  
5.4  
5.5  
182.0kΩ  
63.3kΩ  
24.1kΩ  
4.4kΩ  
R1 = (Blue)  
R2 = Black  
For technical support and more information, see inside back cover or visit www.ti.com/powertrends  
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