Electronic Components Datasheet Search |
|
PT6442 Datasheet(PDF) 5 Page - Texas Instruments |
|
PT6442 Datasheet(HTML) 5 Page - Texas Instruments |
5 / 8 page Application Notes For technical support and more information, see inside back cover or visit www.ti.com PT6440 Series Adjusting the Output Voltage of the PT6440 Excalibur 5V/3.3V Bus Step-Down ISRs The output voltage of the PT6440 Series ISRs may be adjusted higher or lower than the factory trimmed pre- set voltage with the addition of a single external resistor. Table 1 gives the allowable adjustment range for each model for either series as Va (min) and Va (max). Adjust Up: An increase in the output voltage is obtained by adding a resistor R2, between Vo Adj (pin 12) and GND (pins 5–8). Adjust Down: Add a resistor (R1), between Vo Adj (pin 12) and Vout (pins 9–11). Figure 1 The values of (R1) [adjust down], and R2 [adjust up], can also be calculated using the following formulas. Refer to Figure 1 and Table 2 for both the placement and value of the required resistor; either (R1) or R2 as appropriate. (R1) = Ro (Va – 0.9) – Rs k Ω Vo – Va R2 = 0.9 Ro – Rs k Ω Va – Vo Where: Vo = Original output voltage Va = Adjusted output voltage Ro = The resistance value from Table 1 Rs = The series resistance from Table 1 Table 1 ISR ADJUSTMENT RANGE AND FORMULA PARAMETERS Series Pt. # PT6441 PT6442 PT6443 PT6444 PT6445 PT6446 PT6447 Vo (nom) 3.3 2.5 2.0 1.8 1.5 1.2 1.0 Va (min) 2.88 1.97 1.64 1.5 1.3 1.08 0.97 Va (max) 3.5 2.95 2.45 2.25 1.95 1.65 1.45 Ro (kΩ Ω) 10.0 10.0 10.0 10.0 10.0 10.0 10.2 Rs (k Ω) 49.9 20.0 20.0 20.0 20.0 20.0 20.0 R 2 Adjust Up C 2 +V O COM COM +V IN + (R 1) Adj Down PT6440 2,3,4 5–8 12 9,10,11 Vin Vo Vo(adj) GND C 1 + 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. Never connect capacitors from Vo adj to either GND or Vout. Any capacitance added to the Vo adjust pin will affect the stability of the ISR. 3. For each model, adjustments to the output voltage may place additional limits on the minimum input voltage. The revised minimum input voltage must comply with the following requirement. Vin(min) = (Va + 0.5)V or as specified in the data sheet, whichever is greater. |
Similar Part No. - PT6442 |
|
Similar Description - PT6442 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |