TLF50281EL Infineon Technologies, TLF50281EL Datasheet
TLF50281EL
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TLF50281EL Summary of contents
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2.2 MHz Step-Down Regulator 500 mA, low quiescent current 5.0V-Version Rev. 1.0, 2011-10- ...
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... Enable and Thermal Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 7.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 7.2 Electrical Characteristics Module Enable, Bias and Thermal Shutdown . . . . . . . . . . . . . . . . . . . . . . 28 8 Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 8.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 8.2 Electrical Characteristics Module Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 9 Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 9.1 General Layout recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 9.1.1 Additional information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 10 Package Outlines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 11 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Data Sheet 2 TLF50281EL Table of Contents Rev. 1.0, 2011-10-24 ...
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... The TLF50281EL is a high frequency PWM step-down DC/DC converter with an integrated PMOS power switch, packaged in a small PG-SSOP-14 with exposed pad. The wide input voltage range from 4. makes the TLF50281EL suitable for a wide variety of applications. The device is designed to be used under harsh automotive environmental conditions. ...
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... The TLF50281EL includes protection features such as a cycle-by-cycle current limitation, over-temperature shutdown and input under voltage lockout. The enable function, in shutdown mode with less than 2 µA current consumption, enables easy power management in battery-powered systems. The voltage regulation loop provides an excellent line and load regulation, the stability of the loop is ensured by an internal compensation network ...
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... WI WO Figure 1 Block Diagram Data Sheet TLF50281EL Over Temperature Shutdown 14 Enable Buck Converter 5 Oscillator 4 Bandgap Reference Soft Start Ramp Generator 3 Reset Watchdog Generator WMSEL GND GND 5 TLF50281EL Block Diagram SWO INT. SUPPLY RTADJ GND Rev. 1.0, 2011-10-24 ...
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... Connect this pin directly to the output capacitor. Also input for internal power supply. The internal power supply is taken from the output voltage. Data Sheet TLF50281EL PG-SSOP14 6 TLF50281EL Pin Configuration GND 12 11 SWO GND 10 9 GND WMSEL 8 Rev. 1.0, 2011-10-24 ...
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... Switch to high level to enable the device, switch to low level to disable the device. Exposed Pad Connect to heatsink area and GND by low inductance wiring. Data Sheet for Watchdog slow mode or to GND for Watchdog fast mode. If not used, connect 7 TLF50281EL Pin Configuration Rev. 1.0, 2011-10-24 ...
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... FB 6 -2.0 + 0.3 SWO -40 150 j T -55 150 stg ESD V -500 500 ESD V -750 750 ESD 8 TLF50281EL Unit Conditions V – V – < 10s V – < – < 10s V – < 10s V – < 10s V – ...
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... Symbol Limit Values Min. Typ. Max. R – 10 – thJC R – 47 – thJA R – 54 – thJA R – 64 – thJA 9 TLF50281EL General Product Characteristics Unit Conditions V – µH – µF – Ω 1) – °C – Unit Conditions K/W – K/W 2s2p 2 K/W 1s0p + 600 mm 2 K/W 1s0p + 300 mm ...
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... The error amplifier EA-gmV, which is controlling the output voltage in PWM mode, and the PFM comparator, which will switch the TLF50281EL into PFM mode and trigger the pulses. The error amplifier EA-gmV is connected to the PWM comparator. The regulation ...
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... Shutdown). Thus the power consumption from the supply voltage - CS-gmI PFM Comparator VBG - - PWM Comp EA-gmV Slope SoftStart Comp. 11 TLF50281EL Buck Regulator ensures, that the inrush current will be limited. T and restart with a j,sd Shutdown (for details please refer to CC Driver PWM ...
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... PFM (Pulse Frequency Modulation) Mode To optimize the efficiency and to reduce the current consumption, the TLF50281EL automatically switches to PFM mode under low load conditions. In PFM mode the internal power stage including the driver stage is switched off and will only be switched on for applying pulses to charge the output capacitor. The pulses will be created by ...
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... FREQ switched from CC REF_PWM V in PFM mode due to sudden load CC V which is equal to (or slightly higher) in PFM FB V REF_PFM i PWM/PFM i 3 time time Switch to PFM mode V PWM/PFM V REF_PWM time 4 Rev. 1.0, 2011-10-24 TLF50281EL (which is equal a pulse of the ...
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... PFM/PWM D T with the on-time 2 ON2 R . FREQ ON,min TLF50281EL Buck Regulator I will vary. The diagram shows applied to the regulator output The regulator is in PFM mode, PFM/PWM V touches the PFM reference voltage The regulator is still in PFM FREQ of the internal power stage ...
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... PWM to PFM capacitor . OUT set by the frequency setting resistor OSC PWM to PFM i i PWM/PFM PFM/PWM 15 TLF50281EL Buck Regulator I is decreasing the regulator will switch FREQ PFM to PWM f PFM/PWM f PWM Output Current (log.scale) Rev. 1.0, 2011-10-24 ...
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... V 3.75 – S,off V – – S,on V 130 300 S,hyst V – – PWM/PFM f / – 1.20 PFM/PWM f osc Range”. 16 TLF50281EL Buck Regulator Unit Conditions Max < < 12V S I 100 mA < < 610 mA CC PWM Mode 10V < < 35V 100 µ ...
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... 150° 5,100 5,075 5,050 5,025 5,000 4,975 4,950 4,925 4,900 Icc (mA) Data Sheet Load Regulation PWM Mode 25° 5,100 5,075 5,050 5,025 5,000 4,975 4,950 4,925 4,900 Icc (mA) 17 TLF50281EL Buck Regulator Rev. 1.0, 2011-10-24 ...
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... CC J 5,3000 5,2750 5,2500 5,2250 5,2000 5 1750 5,1750 5,1500 5,1250 5,1000 VS (V) Power Stage On Resistance: Black = - 43 °C, Dark Grey T Light Grey J 1,400 1,200 1,000 0,800 0,600 0,400 0,200 0,000 Iswo(A) 18 TLF50281EL Buck Regulator 25° 150 ° Rev. 1.0, 2011-10-24 ...
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... Efficiency for 2.2 MHz, = 4.7 µH OSC OUT 90,00% 80,00% 70,00% 60,00% 50,00% 40,00% 30,00% 20,00% 10,00% 0 200 Data Sheet Efficiency for f = 1.65 MHz, OSC 90,00% 80,00% 70,00% 60,00% 50,00% 40,00% 30,00% 20,00% 10,00% 0,00% 400 600 Efficiency for f = 2.2 MHz, OSC 90,00% 80,00% 70,00% 60,00% 50,00% 40,00% 30,00% 20,00% 10,00% 0,00% 400 600 19 TLF50281EL Buck Regulator µH OUT 0 200 400 µH OUT 0 200 400 Rev. 1.0, 2011-10-24 600 600 ...
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... ⎛ ⎞ for t + < ( -------------------- - V V ⎝ ⎠ TLF50281EL Reset and Watchdog V . The result is monitored by the status above the desired reset threshold. A low adding an external resistor RO,T (where the reset generator indicates an under R2 ⎞ ⎠ and a valid high signal ...
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... The recommended maximum value for the sum of both resistors R1 and R2 of the external resistor divider is 1.2 MΩ Data Sheet Figure 7 another voltage source is necessary. If the supply ( < TLF50281EL Reset and Watchdog V ) voltage is below Rev. 1.0, 2011-10-24 ...
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... R,S,MAX I – – 1 RO,L,MAX V 0.96 1.00 1.04 RO – 150 RO,T,Hyst I -1 0.1 1 RTADJ,MAX – TLF50281EL Reset and Watchdog Unit Conditions V ≥ 1V < 0.9V, CC RTADJ 5V < 0.9V, CC RTADJ µ – mV Output voltage decreasing V = 1.2V µA ...
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... CC Figure 9 and Figure 10 Both watchdog period sam . After receiving a valid trigger signal within the “Trigger Window” the watchdog t sam 23 TLF50281EL Reset and Watchdog R WMSEL,INT R t and watchdog sampling time WD,p before the beginning of the “Trigger Window”, Rev. 1.0, 2011-10- S,off ...
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... improve immunity against noise or glitches on the watchdog input, WI,L Trigger Window 1 Trigger Window 2 Watchdog Decoder Sample Point TLF50281EL Reset and Watchdog t depends on the sam then the watchdog output WO will WD,p Watchdog Output (WO) Invalid Valid or another voltage source is necessary. If the ...
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... RD Signal t < WD,p Missing 4.Correct Correct 3.Correct Trigger Trigger Trigger Trigger Signal causing Watchdog t RD Signal 25 TLF50281EL Reset and Watchdog Power Fail Correct Correct Correct Trigger Trigger Trigger Reset Signal causing Watchdog Signal Power Fail Correct ...
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... Trigger Trigger Trigger Trigger t < < t WD,p(FAST) Valid Valid Valid Valid Valid Valid Valid Trigger Trigger Trigger Trigger Trigger Trigger Trigger 26 TLF50281EL Reset and Watchdog < t WD,p(FAST Valid Valid Valid Valid Trigger Trigger Trigger Trigger ...
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... WD,p 51.2 64 76.8 R 1.25 1.67 – WI,INT V – 0.2 0.4 WO – – WO,L,MAX I – – 1 WO,H,MAX 27 TLF50281EL Reset and Watchdog Unit Conditions V – V – μ WMSEL ΜΩ – V – V – μ μ 0.4V; < 105° fast watchdog timing ms slow watchdog timing ...
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... EN,hi V – – EN, 200 EN,HY I – – EN,hi I – 0.1 EN, EN,INT T 155 175 j, j,sd_hyst 28 TLF50281EL Enable and Thermal Shutdown V ) turns the regulator off. EN,lo Unit Conditions Max µ < 105° µA = 5.0V 5.4V < 105°C; j PFM mode ...
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... PWM FREQ f 2600 2200 osc Resistor at FREQ pin [kΩ] f versus Frequency setting Resistor OSC 29 TLF50281EL Oscillator R between pin FREQ and GND using FREQ Figure 13 below 100 kΩ kHz 1950 1400 1200 105 115 125 135 ...
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... V 2.9 – – SYNC,H V – – 0.8 SYNC,L R 0.15 0.25 0.35 SYNC,INT t 25 – – SYNC,H, min t 25 – – SYNC,L,min 30 TLF50281EL Oscillator Unit Conditions V kHz = 0V; SYNC R = 47kΩ FREQ kHz – MΩ SYNC ns – ns – Rev. 1.0, 2011-10-24 ...
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... IN IN1 IN3 suppression of EME, D depending on application IN L OUT SWO D CATCH RTADJ RO R2 GND Remark For improving EME 1 A current capability 4.7 µH also possible V set to 4 set to 4 set to 2.2 MHz OSC Rev. 1.0, 2011-10-24 TLF50281EL OUT To µP ...
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... Data Sheet and C ): Only the alternate content of the input IN2, IN3 OUT OUT ): Output current ripple Δ and C CATCH OUT OUT CATCH 32 TLF50281EL Application Information , and output capacitor C . OUT Rev. 1.0, 2011-10-24 ...
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... Pin FMEA; • for existing application notes with more detailed information about the possibilities of this device; • for further information you may contact Data Sheet . OUT in the application diagram) in parallel to the output IN3 http://www.infineon.com/ 33 TLF50281EL Application Information Rev. 1.0, 2011-10-24 ...
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... For further package information, please visit our website: http://www.infineon.com/packages. Data Sheet C 0.08 C 14x 0. Exposed B Diepad 0 TLF50281EL Package Outlines 0.35 x 45˚ 3.9 ±0.1 6 ±0.2 0 Bottom View 3 ±0 PG-SSOP-14-1,-2,-3-PO V02 Dimensions in mm Rev. 1.0, 2011-10-24 ...
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... Revision History Rev Version Date Changes Rev 1.0 2011-10-24 Initial data sheet Data Sheet 35 TLF50281EL Revision History Rev. 1.0, 2011-10-24 ...
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... Infineon Technologies Office. Infineon Technologies components may be used in life-support devices or systems only with the express written approval of Infineon Technologies failure of such components can reasonably be expected to cause the failure of that life-support device or system or to affect the safety or effectiveness of that device or system. Life support devices or systems are intended to be implanted in the human body or to support and/or maintain and sustain and/or protect human life ...