L6910 STMicroelectronics, L6910 Datasheet
L6910
Specifications of L6910
497-4220-5
497-4220-5
Available stocks
Related parts for L6910
L6910 Summary of contents
Page 1
... VCC OCSET MONITOR PROTECTION & REF SS OSC PWM E COMP D03IN1509 L6910A HTSSOP16 (Exposed Pad) Package L6910 SO-16 L6910TR SO-16 in Tape & Reel L6910A HTSSOP16 L6910ATR HTSSOP16 in Tape & Reel 12V in BOOT UGATE V BOOT O LGATE PGND GND VFB L6910 output Rev. 9 1/29 ...
Page 2
... L6910 - L6910A Table 2. Absolute Maximum Ratings Symbol Vcc Vcc to GND, PGND V - Boot Voltage BOOT V PHASE V - HGATE V 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 Table 3. Thermal Data ...
Page 3
... This pin is not internally bonded. It may be left floating or connected to GND. Description 4. 200KHz = + ------------------------ - OSC, from this pin to Vcc (12V), the switching frequency is reduced T 4.306 200KHz – ---------------------------- - OSC, OCSET OCSET I = --------------------------------------------- - P R DSon TO A VOLTAGE GREATER THAN V IN L6910 - L6910A ) from this pin 3/29 ...
Page 4
... L6910 - L6910A 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 ...
Page 5
... MOSFET(s) that eliminates the need for a cur- DS(ON) 4. 200KHz + ------------------------- OSC, the frequency is reduced (current is forced into the pin), according CC 4.306 10 = 200KHz – ---------------------------- - 200KHz = – --------------------- OSC, 10000 1000 100 RT to GND VCC=12V RT to VCC=5V 10 100 Frequency [kHz] L6910 - L6910A ) connected between 12V 1000 5/29 ...
Page 6
... L6910 - L6910A 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 100 A 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 ...
Page 7
... 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 L6910 - L6910A = 5V, and the sink peak (left) CC 7/29 ...
Page 8
... L6910 - L6910A 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 ...
Page 9
... rms OUT ESR I rms is then compared with the oscillator triangular wave to provide COMP at the PHASE node. This wave is filtered by the IN depending on the L-C resonance and a zero out L6910 - L6910A -------------- - V OUT – MAX OUT – /V OUT COMP depending on the ESR divided by the peak-to-peak IN ...
Page 10
... L6910 - L6910A 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° ...
Page 11
... PHASE 10 7 GND LGATE 14 EAREF 8 PGND 13 PGOOD VREF OSC COMP VFB C19 R5 R3 C20 R4 C18 D03IN1513 L6910 - L6910A P1 P2 input. 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 ...
Page 12
... L6910 - L6910A Table 6. Part List Reference R1 R2 10K R3 4.7K R4 1KOhm 5% 125mW R5 2.7K R6 10Ohm 5% 125mW R7 510Ohm 5% 125mW R8 R9 R10 14K R11 6.98K R12 2.61K R13 1.74K C1, C3 C9, C10 C12, C13, C15, C21 C14 C16 C17 C18 C19 C20 C22 (T50-52B Core, 7T AWG15) ...
Page 13
... Figure 14. PCB and Components Layouts Internal Power GND Layer Figure 15. Efficiency vs Output Current 100 100 Vin=Vcc=5V Vin=Vcc= Fsw=200KHz Fsw=200KHz Output Current (A) L6910 - L6910A 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. 13/29 ...
Page 14
... L6910 - L6910A 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 H. ...
Page 15
... OSC 2 2 PGOOD PGOOD 9 9 EAREF EAREF 8 8 VREF VREF VFB VFB COMP COMP R5 R5 C19 C19 C18 C18 R1 R1 L6910 - L6910A (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 ...
Page 16
... L6910 - L6910A Table 9. Part List Reference Description Resistor R1 2K7 Ohm 0805 5% 125mW 1K8 Ohm 0805 5% 125mW 1K Ohm 0805 5% 125mW R2 10K 5% 125mW R3 4K7 5% 125mW R4 4K7 5% 125mW R5 2K7 5% 125mW R6 10 Ohm 5% 125mW R7 680 Ohm 5% 125mW R8 R9 2.2 Ohm 5% 125mW R10 N.C R11 N.C ...
Page 17
... 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) L6910 - L6910A 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. 17/29 ...
Page 18
... L6910 - L6910A 8 15A HTSSOP16 DEMO BOARD DESCRIPTION A specific Demo Board has been realized for the HTSSOP16 package. The features are the same of the 15A Demo Board previously described but thermal performance are improved. The PGOOD signal is used as a logic level and it's been pulled case of input voltage higher than 7V (PGOOD Pin Maximum Absolute Rating reference is re- quired ...
Page 19
... N.C N.C Short STS11NF30L 1N4148 STPS340U Device L6910 Short DIP SWITCH Series Inductor Value ( H) 744318 ETQP6F1R8FA CDEP134-2R7MC-H L6910 - L6910A Manufacturer KEMET KEMET AVX KEMET KEMET KEMET MICROMETALS HTSSOP16 Saturation Current (A) 1 1.8 20 2.7 15 ...
Page 20
... The current required by the memory and the termination supply, depends on the memory type and size. The figure 24, 25 shows the efficiency of the L6910 for the termination section of the application shown in fig. 23, in sink and source mode. The figures show the efficiency values also when the input voltage is coming di- rectly from the 12V rail ...
Page 21
... Figures 26, 27 and 28, 29 show the efficiency of the L6910 in sink and source mode 17A both for DDRI and DDRII memories.The measurements have been re- alized with the 15A demo board. (See pag.11 ) Figure 26 ...
Page 22
... L6910 - L6910A 10 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. ...
Page 23
... STS11NF30L STS5P30L 1N4148 Device L6910 Vin=5V Vin=5V Vin=3.3V Vin=3.3V 1.5 1 2.5 2.5 Output Current (A) Output Current (A) L6910 - L6910A Manufacturer NEOHM SMD 0805 NEOHM SMD 0805 NEOHM SMD 0805 NEOHM SMD 0805 NEOHM SMD 0805 NEOHM SMD 0805 NEOHM SMD 0805 OSCON 20SA100M RADIAL 10X10 ...
Page 24
... L6910 - L6910A 11 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 ...
Page 25
... Description 47nF Open STS11NF30L 1N4148 Device L6910 Vin=3.3V Vin=3. Fsw=200KHz Fsw=200KHz 1.5 1 Output Current Output Current (A) (A) L6910 - L6910A KEMET SMD0805 KEMET SMD0805 Manufacturer KEMET SMD0805 Jumper MAGNETICS ST SO8 SOT23 ST SMB (D0144) ST SO16 Narrow Vin=5V Vin=5V 2.5 2 25/29 ...
Page 26
... L6910 - L6910A Figure 34. HTSSOP16 (Exposed pad) Mechanical Data & Package Dimensions mm DIM. MIN. TYP. MAX. A 1.2 A1 0.15 A2 0.8 1.0 1.05 b 0.19 0.3 c 0.09 0.2 D (*) 4.9 5.0 5.1 D1 1.7 E 6.2 6.4 6.6 E1 (*) 4.3 4.4 4.5 E2 1.5 e 0.65 L 0.45 0.6 0.75 L1 1.0 k 0˚ (min), 8˚ (max) aaa 0 ...
Page 27
... MIN. TYP. MAX. 0.069 0.004 0.009 0.063 0.014 0.018 0.007 0.010 0.020 (typ.) 0.386 0.394 0.228 0.244 0.050 0.350 0.150 0.157 0.181 0.208 0.150 0.050 0.024 (max.) L6910 - L6910A OUTLINE AND MECHANICAL DATA SO16 (Narrow) 0016020 D 27/29 ...
Page 28
... L6910 - L6910A Table 1. Revision History Date Revision January 2004 August 2004 May 2005 28/29 7 Migration from ST-Press to EDOCS dms. 8 Changed any figures and textes; add. the section “15A HTSSOP16 Demo Board Description”. Changed the style-look following the new “Corporate Technical Pubblications Design Guide” ...
Page 29
... Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America All other names are the property of their respective owners © 2005 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com L6910 - L6910A 29/29 ...