Moteur de recherche de fiches techniques de composants électroniques |
|
TPS73701DCQR Fiches technique(PDF) 11 Page - Texas Instruments |
|
|
TPS73701DCQR Fiches technique(HTML) 11 Page - Texas Instruments |
11 / 22 page APPLICATION INFORMATION INPUT AND OUTPUT CAPACITOR TPS737xx GND EN IN OUT V IN V OUT ON OFF OUTPUT NOISE TPS73701 GND EN FB IN OUT V IN V OUT V OUT = x1.204 (R 1 + R2) R 2 R 1 C FB R 2 Optionalinputcapacitor. Mayimprovesource impedance,noise,orPSRR. Outputcapacitor mustbe 1.0 F. ³ m Optionalcapacitor reducesoutputnoise andimproves transientresponse. OFF ON V N + 32mVRMS (R 1 ) R2) R 2 + 32mVRMS V OUT V REF (1) V N mVRMS + 27 mVRMS V V OUT (V) (2) TPS737xx www.ti.com.................................................................................................................................................... SBVS067I – JANUARY 2006 – REVISED MARCH 2009 in addition to the internal 8k Ω resistor, presents the The TPS737xx belongs to a family of new generation same impedance to the error amp as the 27k Ω LDO regulators that use an NMOS pass transistor to bandgap reference output. This impedance helps achieve ultra-low-dropout performance, reverse compensate for leakages into the error amp current blockage, and freedom from output capacitor terminals. constraints. These features combined with an enable input make the TPS737xx ideal for portable applications. This regulator family offers a wide REQUIREMENTS selection of fixed output voltage versions and an adjustable output version. All versions have thermal Although an input capacitor is not required for stability and over-current protection, including foldback if input impedance is very low, it is good analog current limit. design practice to connect a 0.1 µF to 1µF low equivalent series resistance (ESR) capacitor across Figure 31 shows the basic circuit connections for the the input supply near the regulator. This capacitor fixed voltage models. Figure 32 gives the connections counteracts reactive input sources and improves for the adjustable output version (TPS73701). transient response, noise rejection, and ripple rejection. A higher-value capacitor may be necessary if large, fast rise-time load transients are anticipated or the device is located several inches from the power source. The TPS737xx requires a 1.0µF output capacitor for stability. It is designed to be stable for all available types and values of capacitors. In applications where multiple low ESR capacitors are in parallel, ringing Figure 31. Typical Application Circuit for may occur when the product of COUT and total ESR Fixed-Voltage Versions drops below 50n ΩF. Total ESR includes all parasitic resistances, including capacitor ESR and board, socket, and solder joint resistance. In most applications, the sum of capacitor ESR and trace resistance will meet this requirement. A precision bandgap reference is used to generate the internal reference voltage, VREF. This reference is the dominant noise source within the TPS737xx and it generates approximately 32 µV RMS (10Hz to 100kHz) at the reference output (NR). The regulator control loop gains up the reference noise with the same gain as the reference voltage, so that the noise voltage of the regulator is approximately given by: Figure 32. Typical Application Circuit for Adjustable-Voltage Version Since the value of VREF is 1.2V, this relationship R1 and R2 can be calculated for any output voltage reduces to: using the formula shown in Figure 32. Sample resistor values for common output voltages are shown in Figure 2. For best accuracy, make the parallel combination of R1 and R2 approximately equal to 19kΩ. This 19kΩ, for the case of no CNR. Copyright © 2006–2009, Texas Instruments Incorporated Submit Documentation Feedback 11 |
Numéro de pièce similaire - TPS73701DCQR |
|
Description similaire - TPS73701DCQR |
|
|
Lien URL |
Politique de confidentialité |
ALLDATASHEET.FR |
ALLDATASHEET vous a-t-il été utile ? [ DONATE ] |
À propos de Alldatasheet | Publicité | Contactez-nous | Politique de confidentialité | Echange de liens | Fabricants 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 |