L6712QTR STMicroelectronics, L6712QTR Datasheet
L6712QTR
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L6712QTR Summary of contents
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... Over-voltage is detected. Output current is limited working in Constant Cur- rent mode: when Under Voltage is detected, the device resets, restarting operation. L6712 L6712A SO28 VFQFPN-36 (6x6x1.0mm) Tube Tape & Reel L6712DTR, L6712ADTR L6712QTR, L6712AQTR Rev. 3 1/29 ...
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L6712A L6712 Figure 2. Block Diagram BAND-GAP BAND-GAP REFERENCE REFERENCE PGOOD PGOOD LOGIC AND LOGIC AND VID2 VID2 PROTECTIONS PROTECTIONS VID1 VID1 DAC DAC VID0 VID0 DIGITAL DIGITAL SOFT-START SOFT-START V V REF_IN/OUT REF_IN/OUT FBG FBG FBR FBR REMOTE REMOTE ...
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Figure 3. Pin Connection (Top view) LGATE1 1 28 VCCDR 2 27 PHASE1 3 26 UGATE1 4 25 BOOT1 5 24 VCC 6 23 SGND 7 22 COMP DROOP 10 19 REF_IN/OUT 11 18 VSEN ...
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L6712A L6712 Table 4. Electrical Characteristcs (continued 12V±10 0°C to 70°C unless otherwise specified Symbol Parameter REFERENCE AND DAC Output Voltage Accuracy VIDx See Table 5, VID ≠ “11x“ (1) V OUT REF_IN/OUT Reference ...
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Table 4. Electrical Characteristcs (continued 12V±10 0°C to 70°C unless otherwise specified Symbol Parameter PROTECTIONS PGOOD Upper Threshold Lower Threshold OVP Over Voltage Threshold UVP Under Voltage Trip V PGOOD Voltage Low PGOODL I ...
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L6712A L6712 Table 6. Pin Function (continued) N. (*) Name SO VFQFPN 10 9 DROOP 11 11 REF_IN / OUT 12 12 VSEN 13 13 ISEN1 14 14 PGNDS1 15 15 PGNDS2 16 16 ISEN2 17 18 OSC/INH FAULT 18 ...
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Table 6. Pin Function (continued) N. (*) Name SO VFQFPN VID0 PGOOD 24 27 BOOT2 25 28 UGATE2 26 29 PHASE2 27 30 LGATE2 28 31, PGND 32 PAD THERMAL PAD (*) ...
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L6712A L6712 3 Device Description The device is an integrated circuit realized in BCD technology. It provides complete control logic and pro- tections for a high performance dual-phase step-down converter optimized for high current DC/DC appli- cations designed ...
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Figure 5. R vs. Switching Frequency OSC 14000 12000 10000 8000 6000 4000 2000 Frequency (kHz) 3.2 DIGITAL TO ANALOG CONVERTER AND REFERENCE The built-in digital to analog converter allows the adjustment of the output voltage ...
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L6712A L6712 Figure 6. Reference Management BAND-GAP REFERENCE (1.235V) VID3 VID2 VID1 REF_IN/OUT The output regulated voltage accuracy can be extracted from the following relationships (worst case con- dition OUT_TOT_ACC [ ] ...
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DRIVER SECTION The integrated high-current drivers allow using different types of power MOS (also multiple MOS to reduce the R ), maintaining fast switching transition. dsON The drivers for the high-side mosfets use BOOTx pins for supply and PHASEx ...
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L6712A L6712 circuitry reads the current during the time in which the low-side mosfet is on (OFF Time). During this time, the reaction keeps the pin ISENx and PGNDSx at the same voltage while during the time in which the ...
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I OCPx Since the device senses the output current across the low-side mosfets (or across a sense resistors in series with them) the device limits the bottom of the inductor current triangular waveform: an over current is detected when the ...
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L6712A L6712 usual way until another OCP event is detected. This means that the average current delivered can slightly increase also in Over Current condition since the current ripple increases. In fact, the ON time increases due to the OFF ...
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L6712A - Fixed Maximum Duty Cycle Limitation The maximum duty cycle is fixed and constant with the delivered current. The device works in constant ...
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L6712A L6712 3.6 INTEGRATED DROOP FUNCTION (Optional) Droop function realizes dependence between the regulated voltage and the delivered current (Load Reg- ulation). In this way, a part of the drop due to the output capacitor ESR in the load transient ...
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The reference used in this case to determine the UV thresholds is the increasing voltage driven by the 2048 soft start digital counter while the reference used for the OV threshold is the final reference programmed ...
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L6712A L6712 3.9 INPUT CAPACITOR The input capacitor is designed considering mainly the input RMS current that depends on the duty cycle as reported in Figure 15. Considering the two-phase topology, the input RMS current is highly reduced comparing with ...
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The voltage drop due to the output capacitor discharge is given by the following equation: Where D is the maximum duty cycle value. The lower is the ESR, the lower is the output drop during MAX load transient and ...
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L6712A L6712 Figure 16. Main Control Loop Diagram + + D03IN1518 3.12.1Current Sharing (CS) Control Loop Active current sharing is implemented using the information from Trans conductance differential amplifier. A current reference equal to the average of the read current ...
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Where ∆I is the difference between one phase current and the ideal current (I READ For R = 4mΩ and I = 40A the current sharing error is equal to 2.5%, neglecting errors due to Rg SENSE MAX and R ...
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L6712A L6712 Figure 18. ACM Control Loop Gain Block Diagram (left) and Bode Diagram (right). I DROOP Z F DROOP COMP FB COMP VID L/2 V OUT PWM d•V IN Cout ESR The ...
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Integrated power drivers reduce components count and interconnections between control functions and drivers, reducing the board space. Here below are listed the main points to focus on when starting a new layout and rules are suggested for a correct implementation. ...
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L6712A L6712 implemented the same way to the LS mosfets Source pin. GATEx and PHASEx connections (and also PGND when no power ground plane is implemented) must also be designed to handle current peaks in excess of 2A ...
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Current Reading: The Rg resistor has to be placed as close as possible to the ISENx and PGNDSx pins in order to limit the noise injection into the device. The PCB traces connecting these resistors to the read- ing ...
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L6712A L6712 4 Package informations Figure 22. SO-28 Mechanical Data & Package Dimensions mm DIM. MIN. TYP. MAX. A 2.65 a1 0.1 0.3 b 0.35 0.49 b1 0.23 0.32 C 0.5 c1 45° (typ.) D 17.7 18 10.65 ...
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Figure 23. VFQFPN-36 Mechanical Data & Package Dimensions mm DIM. MIN. TYP. MAX. A 0.800 0.900 1.000 A1 0.020 0.050 A2 0.650 1.000 A3 0.250 b 0.180 0.230 0.300 D 5.875 6.000 6.125 D2 1.750 3.700 4.250 E 5.875 6.000 ...
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L6712A L6712 5 Revision History Table 7. Revision History Date Revision March 2004 June 2005 28/29 2 First Issue in EDOCS. 3 Changed look and feel. Inserted “Boot Capacitor Extra Charge” paragraph to page 27. Description of Changes ...
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... 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. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics ...