Motor de Búsqueda de Datasheet de Componentes Electrónicos |
|
TPS62171DSGR Datasheet(PDF) 9 Page - Texas Instruments |
|
|
TPS62171DSGR Datasheet(HTML) 9 Page - Texas Instruments |
9 / 34 page ( ) ns L V V I I OUT IN HS LIMF typ peak 30 × - + = _ ) ( PD L LIMF typ peak t L V I I × + = ) ( 9 TPS62170, TPS62171, TPS62172, TPS62173 www.ti.com SLVSAT8D – NOVEMBER 2011 – REVISED DECEMBER 2015 Product Folder Links: TPS62170 TPS62171 TPS62172 TPS62173 Submit Documentation Feedback Copyright © 2011–2015, Texas Instruments Incorporated Feature Description (continued) where • ILIMF is the static current limit, specified in Electrical Characteristics • L is the inductor value • VL is the voltage across the inductor • tPD is the internal propagation delay (1) space The dynamic high-side switch peak current is calculated as follows: space (2) Take care with the current limit, if the input voltage is high and very small inductances are used. 8.3.3 Power Good (PG) The TPS6217x has a built in power good (PG) function to indicate whether the output voltage has reached its appropriate level or not. The PG signal can be used for startup sequencing of multiple rails. The PG pin is an open-drain output that requires a pull-up resistor (to any voltage below 7 V). It can sink 2 mA of current and maintain its specified logic low level. It is high impedance when the device is turned off due to EN, UVLO or thermal shutdown. 8.3.4 Undervoltage Lockout (UVLO) If the input voltage drops, the under voltage lockout prevents misoperation of the device by switching off both the power FETs. The under voltage lockout threshold is set typically to 2.7 V. The device is fully operational for voltages above the UVLO threshold and turns off if the input voltage trips the threshold. The converter starts operation again once the input voltage exceeds the threshold by a hysteresis of typically 180 mV. 8.3.5 Thermal Shutdown The junction temperature (Tj) of the device is monitored by an internal temperature sensor. If Tj exceeds 160°C (typical), the device goes into thermal shut down. Both the high-side and low-side power FETs are turned off and PG goes high impedance. When Tj decreases below the hysteresis amount, the converter resumes normal operation, beginning with soft start. To avoid unstable conditions, a hysteresis of typically 20°C is implemented on the thermal shut down temperature. 8.4 Device Functional Modes 8.4.1 Soft Start The internal soft start circuitry controls the output voltage slope during startup. This avoids excessive inrush current and ensures a controlled output voltage rise time. It also prevents unwanted voltage drops from high- impedance power sources or batteries. When EN is set to start device operation, the device starts switching after a delay of about 50 µs and VOUT rises with a slope of about 25 mV/µs. See Figure 30 and Figure 31 for typical startup operation. The TPS6217x can start into a pre-biased output. During monotonic pre-biased startup, the low-side MOSFET is not allowed to turn on until the device's internal ramp sets an output voltage above the pre-bias voltage. |
Número de pieza similar - TPS62171DSGR |
|
Descripción similar - TPS62171DSGR |
|
|
Enlace URL |
Política de Privacidad |
ALLDATASHEET.ES |
¿ALLDATASHEET es útil para Ud.? [ DONATE ] |
Todo acerca de Alldatasheet | Publicidad | Contáctenos | Política de Privacidad | Intercambio de Enlaces | Lista de Fabricantes 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 |