Motor de Búsqueda de Datasheet de Componentes Electrónicos |
|
LM3503SQ-35NOPB Datasheet(PDF) 7 Page - Texas Instruments |
|
LM3503SQ-35NOPB Datasheet(HTML) 7 Page - Texas Instruments |
7 / 28 page -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 TEMPERATURE ( oC) 0.93 0.94 0.95 0.96 0.97 0.98 0.99 1.00 1.01 1.02 1.03 -40 VIN = 2.5V 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE (V) 0.400 0.440 0.480 0.520 0.560 0.600 2.5 -40 oC 0.420 0.460 0.500 0.540 0.580 125 oC 25 oC En1 En2 0.3V 0.3V Result (See Figure 1 and Figure 2) 1.4V 0.3V 0.3V 1.4V 1.4V 1.4V [P1 ÆOFF N2ÆOFF N1ÆOFF] or [MAINÆOFF SUBÆOFF N1ÆOFF] [P1 ÆOFF N2ÆON N1ÆSwitching] or [MAINÆON SUBÆOFF N1ÆSwitching] [P1 ÆON N2ÆOFF N1ÆSwitching] or [MAINÆOFF SUBÆON N1ÆSwitching] [P1 ÆOFF N2ÆOFF N1ÆSwitching] or [MAINÆON SUBÆON N1ÆSwitching] Shutdown X LM3503 www.ti.com SNVS329D – JULY 2005 – REVISED AUGUST 2006 The LM3503 has two control pins, En1 and En2, used for selecting which segment of a single white LED string network is active for dual display applications. En1 controls the main display (MAIN) segment of the single string white LED network between pins VOUT1 and VOUT2. En2 controls the sub display (SUB) segment of the single string white LED network between the VOUT2 and Fb. If both VEn1 and VEn2 are ≤ 0.3V, the LM3503 will shutdown, for further description of the En1 and En2 operation, see Figure 33. During shutdown the output capacitor discharges through the string of white LEDs and feedback resistor to ground. The LED current can be dynamically controlled by a DC voltage on the Cntrl pin. When VCntrl = 0V the white LED current may not be equal to zero because of offsets within the LM3503 internal circuitry. To guarantee zero white LED current the LM3503 must be in shutdown mode operation. The LM3503 has dedicated protection circuitry active during normal operation to protect the integrated circuit (IC) and external components. Soft start circuitry is present in the LM3503 to allow for slowly increasing the current limit to its steady-state value to prevent undesired high inrush current during start up. Thermal shutdown circuitry turns off the internal NMOS power device, N1, when the internal semiconductor junction temperature reaches excessive levels. The LM3503 has a under-voltage protection (UVP) comparator that disables the internal NMOS power device when battery voltages are too low, thus preventing an on state where the internal NMOS power device conducts large amounts of current. The over-voltage protection (OVP) comparator prevents the output voltage from increasing beyond the protection limit when the white LED string network is removed or if there is a white LED failure. OVP allows for the use of low profile ceramic capacitors at the output. The current through the internal NMOS power device, N1, is monitored to prevent peak inductor currents from damaging the IC. If during a cycle (cycle=1/switching frequency) the peak inductor current exceeds the current limit for the LM3503, the internal NMOS power device will be turned off for the remaining duration of that cycle. Figure 4. Operational Characteristics Table Typical Performance Characteristics (See Typical Application Circuit :e L=DO1608C-223 and D=B150-13. Efficiency: η = POUT/ PIN = [(VOUT – VFb ) * IOUT] / [VIN * IIN]. TA = +25°C, unless otherwise stated.) IQ (Non-Switching) Switching Frequency vs vs VIN Temperature Figure 5. Figure 6. Copyright © 2005–2006, Texas Instruments Incorporated Submit Documentation Feedback 7 Product Folder Links: LM3503 |
Número de pieza similar - LM3503SQ-35NOPB |
|
Descripción similar - LM3503SQ-35NOPB |
|
|
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 |