L6910G STMicroelectronics, L6910G Datasheet
L6910G
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L6910G Summary of contents
Page 1
... In case of over-current detection, the soft start ca- pacitor is discharged and the system works in HICCUP mode. VCC OCSET MONITOR BOOT PROTECTION & REF UGATE OSC PHASE PWM E/A - LGATE + + - PGND GND VFB COMP L6910G SO-16 (Narrow) Package L6910G SO-16 SO-16 in Tape & Reel 12V output Rev. 1 1/26 ...
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... L6910G Table 2. Absolute Maximum Ratings Symbol Vcc Vcc to GND, PGND V -V Boot Voltage BOOT PHASE V -V HGATE PHASE OCSET, LGATE, PHASE SS, FB, PGOOD, VREF, EAREF, RT COMP T Junction Temperature Range j T Storage temperature range stg P Maximum power dissipation at Tamb = 25°C tot OCSET PIN Maximum Withstanding Voltage Range Test Condition: CDF-AEC-Q100-002” ...
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... OSC, from this pin to Vcc (12V), the switching frequency is reduced according to T 4.306 10 = – ---------------------------- - f 200KHz OSC,RT R ⋅ OCSET OCSET = --------------------------------------------- - DSon TO A VOLTAGE GREATER THAN V IN L6910G ) from this pin to GND, the T 6 ⋅ KΩ ⋅ KΩ 3/26 ...
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... L6910G Table 5. Electrical Characteristics (V Symbol Parameter V SUPPLY CURRENT cc Icc Vcc Supply current POWER-ON Turn-On Vcc threshold Turn-Off Vcc threshold Rising V threshold OCSET Turn On EAREF threshold SOFT START AND INHIBIT Iss Soft start Current S.S. current in INH condition OSCILLATOR f Initial Accuracy OSC ...
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... CC ⋅ 4.306 10 = – ---------------------------- - 200KHz ( ) R KΩ ⋅ – --------------------- f 200KHz ( OSC,RT R KΩ T 10000 1000 100 RT to GND VCC=12V RT to VCC=5V 10 100 Frequency [kHz] ) connected between T 6 ⋅ KΩ 12V 1000 L6910G 5/26 ...
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... L6910G 4.2 Reference A precise ±1.5% 0.9V reference is available. This reference must be filtered with 1nF ceramic capacitor to avoid instability in the internal linear regulator able to deliver up to 100µA and may be used as reference for the device regulation and also for other devices. If forced under 70% of its nominal value, the device enters in Hic- cup mode until this condition is removed ...
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... The device provides overvoltage protection, when the voltage sensed on pin FB reaches a value 17% (typ.) greater than the reference the OSC pin is forced high (3V typ.) and the lower driver is turned on as long as the over-voltage is detected. = 12V and 500mA @ 5V 12V (right CH1 = Low Side Gate CH4 = Gate Current = 5V, and the sink peak (left) CC L6910G 7/26 ...
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... L6910G Overcurrent protection is performed by the device comparing the drop across the high side MOS, due to the R , with the voltage across the external resistor (R DSON upper MOS. Thus the overcurrent threshold (I Where the typical value of I OCS R (also the variation with temperature) and the minimum value of I ...
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... COMP at the PHASE node. This wave is filtered by the IN depending on the L-C resonance and a zero out ⋅ I ∆ -------------- - V OUT L ) – MAX OUT ) /V OUT COMP depending on the ESR divided by the peak-to-peak IN L6910G . This function 9/26 ...
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... L6910G Figure 10. Compensation Network The compensation network consists in the internal error amplifier and the impedance networks Z C20) and Z (R5, C18 and C19). The compensation network has to provide a closed loop transfer function with FB the highest 0dB crossing frequency to have fast response (but always lower than fsw/10) and the highest gain in DC conditions to minimize the load regulation. A stable control loop has a gain crossing with -20dB/decade slope and a phase margin greater than 45° ...
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... The four layers demo board's IN because there C1-C3 Q1 OUT Q4-6 C4 GNDOUT PWRGD R8 R9 C22 OUT 0.9 Open Open Open Open 1.2 ON Open Open Open 1.5 Open ON Open Open 1 Open Open 2.5 Open Open ON Open 3.3 Open Open Open ON 5.0 Open Open ON ON L6910G 11/26 ...
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... N.C Short STS11NF30L 1N4148 STPS2L25U Device L6910G Short Series Inductor Value (µH) 744318 ETQP6F1R8FA CDEP134-2R7MC-H Manufacturer NEOHM NEOHM SMD 0805 NEOHM SMD 0805 NEOHM SMD 0805 ...
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... Figure 14. PCB and Components Layouts Internal Power GND Layer Figure 15. Efficiency vs Output Current 100 100 Vin=Vcc=5V Vin=Vcc=5V Fsw=200KHz Fsw=200KHz Output Current (A) L6910G Internal Signal GND Layer Solder Side Vo=3.3V Vo=3.3V Vo=2.5V Vo=2.5V Vo=1.8V Vo=1.8V Vo=1.5V Vo=1.5V Vo=1.2V Vo=1.2V Vo=0.9V Vo=0. 13/26 ...
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... L6910G Figure 16. Efficiency vs Output Current 100 COMPONENTS SELECTION 6.1 Inductor Selection To select the right inductor value, the application conditions must be fixed. For example we can consider: Vin=12V Vout =3.3V Iout=15A Considering a ripple of approximately 25% to 30% of Iout, the inductor value will be L=3 µH. ...
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... C18 C18 R1 R1 (V) V (V) I (A) OUT OUT 1.2 20 1.5 20 1.8 20 2 because there's no other appropriate IN C1 Q1/Q1 Q1/Q1 R11 R11 D2 D2 C10 C10 C3-4 C3-4 Q2/Q1 Q2/ C20 C20 C20 L6910G η (%) VOUT VOUT R2 R2 GNDOUT GNDOUT PWRGD PWRGD 15/26 ...
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... C20 47nF Magnetics L1 7µH (T50-52B Core, 12T AWG 21) Transistor Q1 STS8DNF3LL Diodes D1 1N4148 D2 STPS2L25U Device U1 Device L6910G Table 10. Other inductor manufacturer Manufacturer WÜRTH ELEKTRONIK PANASONIC SUMIDA COILCRAFT COILTRONICS 16/26 POSCAP 6TPB100M 1nF Series Inductor Value (µH) 744 382 ETQP6F CDEP134-H ...
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... Figure 20. Efficiency vs. Output Current Output Current (A) Output Current (A) Vin=Vcc=12V Vin=Vcc=12V Fsw=200KHz Fsw=200KHz Output Current (A) Output Current (A) L6910G Solder Side Vo=3.3V Vo=3.3V Vo=2.5V Vo=2.5V Vo=1.8V Vo=1.8V Vo=1.5V Vo=1.5V Vo=1.2V Vo=1. Vo=5V Vo=5V Vo=3.3V Vo=3.3V Vo=2.5V Vo=2.5V Vo=1.8V Vo=1.8V Vo=1.5V Vo=1.5V Vo=1.2V Vo=1. 17/26 ...
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... The current required by the memory and the termination supply, depends on the memory type and size. The figure 22, 23 shows the efficiency of the L6910G for the termination section of the application shown in fig. 21, in sink and source mode. The figures show the efficiency values also when the input voltage is coming di- rectly from the 12V rail ...
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... Figures 24, 25 and 26, 27 show the efficiency of the L6910G in sink and source mode 17A both for DDRI and DDRII memories.The measurements have been realized with the 15A demo board. (See pag.11 ) Figure 24 ...
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... L6910G 9 APPLICATION IDEA 2: POSITIVE BUCK-BOOST REGULATOR 3V TO 13.2V INPUT / 5V 2.5A OUTPUT In some applications the input voltage changes in a very wide range while the output must be regulated to a fixed value. In this case a Buck-Boost topology can be required in order to keep the output voltage in regulation. ...
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... Open STS11NF30L STS5P30L 1N4148 Device L6910G Vin=5V Vin=5V Vin=3.3V Vin=3.3V 1.5 1 2.5 2.5 Output Current (A) Output Current (A) Manufacturer NEOHM SMD 0805 NEOHM ...
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... L6910G 10 APPLICATION IDEA 3: BUCK-BOOST REGULATOR 3V TO 5.5V INPUT/-5V 3A OUTPUT In applications where a negative output voltage is required, a standard Buck-Boost topology can be implement- ed. The considerations related to the maximum output current are the same of the "Positive Buck-Boost" (Ap- plication Idea 2). A particularity of this topology is that the device undergoes a voltage that is the sum of V verting 5V to -5V, the device undergoes 10V voltage ...
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... STPS3L25U ( STPS340U) U1 Figure 31. Efficiency vs. Output Current Vcc=5V Vcc= Vout= Vout 15nF 1.5nF Description 47nF Open STS11NF30L 1N4148 Device L6910G Vin=3.3V Vin=3. Fsw=200KHz Fsw=200KHz 1.5 1 Output Current Output Current (A) (A) KEMET SMD0805 KEMET SMD0805 Manufacturer KEMET SMD0805 Jumper MAGNETICS ST SO8 SOT23 ST SMB (D0144) ...
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... L6910G Figure 32. SO-16 (Narrow) Mechanical Data & Package Dimensions mm DIM. MIN. TYP. MAX. A 1.75 a1 0.1 0.25 a2 1.6 b 0.35 0.46 b1 0.19 0.25 C 0.5 c1 45° (1) 9 5.8 6.2 e 1.27 e3 8.89 (1) 3.8 4 4.60 5.30 L 0.4 1.27 M 0.62 8 ° (max.) S (1) "D" and "F" do not include mold flash or protrusions - Mold flash or protrusions shall not exceed 0 ...
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... Table 1. Revision History Date Revision May 2005 1 First Issue Description of Changes L6910G 25/26 ...
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... L6910G Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice ...