l6928 STMicroelectronics, l6928 Datasheet
l6928
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l6928 Summary of contents
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... Description The device is dc-dc monolithic regulator specifically designed to provide extremely high efficiency. L6928 supply voltage can be as low as 2V allowing its use in single Li-ion cell supplied applications. Output voltage can be selected by an external divider down to 0.6V. Duty Cycle can saturate to 100% allowing low drop-out operation. ...
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... Slope compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.4 Loop stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 5 Additional features and protections . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.1 DROPOUT operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.2 PGOOD (Power Good Output 5.3 Adjustable output voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.4 OVP (Overvoltage Protection 5.5 Thermal shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 6 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 7 Order codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 8 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2/16 Low consumption mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Low noise mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 L6928 ...
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... L6928 1 Pin settings 1.1 Pin connection Figure 1. Pin connection (top view) 1.2 Pin description Table 1. Pin description Pin N° Name 1 RUN 2 COMP 3 VFB 4 GND VCC 7 SYNC 8 PGOOD RUN 1 COMP 2 VFB 3 GND 4 D01IN1239AMOD Shutdown input. When connected to a low level (lower than 0.4V) the device stops working ...
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... Other pins Acceptance Criteria: “Normal Performance’ 2.2 Thermal data Table 3. Thermal data Symbol Maximum thermal resistance junction-ambient for MSOP8 R thJA Maximum thermal resistance junction-ambient for VFQFPN8 4/16 Parameter = 70°C A Parameter L6928 Value Unit - ...
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... L6928 3 Electrical characteristics Table 4. Electrical characteristcs (T = 25° 3.6V unless otherwise specified Symbol Parameter V Operating input voltage cc V Turn On threshold Turn Off threshold cc OFF V Hysteresis cc hys R High side Ron p R Low side Ron n Peak current limit I lim Valley current limit ...
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... Specification referred to T from -40°C to +125°C. Specification over the -40 to +125° design, characterization and statistical correlation. 2. Guaranteed by design 6/16 (1) Test condition OUT OUT fb Run to GND V = 3.6V PGOOD = V OUT fb L6928 Min Typ Max Unit 1 1 %Vout 4 %Vout 0 ...
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... L6928 4 Operation description The main loop uses slope compensated PWM current mode architecture. Each cycle the high side MOSFET is turned on, triggered by the oscillator, so that the current flowing through it (the same as the inductor current) increases. When this current reaches the threshold (set by the output of the error amplifier E/A), the peak current limit comparator ...
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... The device can also be synchronized with an external signal from 1MHz up to 2MHz. In this case the low noise mode is automatically selected. The device will eventually skip some cycles in very light load conditions. The internal synchronization circuit is inhibited in shortcircuit and overvoltage conditions in order to keep the protections effective (see relative sections). 8/16 L6928 ...
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... L6928 4.2 Short circuit protection During the device operation, the inductor current increases during the high side turn ON phase and decrease during the high side turn off phase based on the following equations: Equation 1 Equation 2 In strong overcurrent or shortcircuit conditions the V case ∆I increases and ∆ ...
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... The right value for the resistor (in the range of 50K) can be determined by checking the load transient response of the device. Basically, the output voltage has to be checked at the scope after the load steps required by the application. In case of stability problems, the output voltage could oscillates before to reach the regulated value after a load step. 10/16 L6928 ...
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... L6928 5 Additional features and protections 5.1 DROPOUT operation The Li-Ion battery voltage ranges from approximately 3V and 4.1V-4.2V (depending on the anode material). In case the regulated output voltage is from 2.5V and 3.3V, it can be that, close to the end of the battery life, the battery voltage goes down to the regulated one. In this case the device stops to switch, working at 100% of duty cycle, so minimizing the dropout voltage and the device losses ...
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... L6928 OUTLINE AND MECHANICAL DATA MSOP8 (Body 3mm) ...
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... L6928 Figure 4. VFQFPN8 mechanical data & package dimensions DIM. MIN 0.30 ddd mm inch TYP. MAX. MIN. TYP. MAX. 0.90 1.00 0.0315 0.0354 0.0394 0.02 0.05 0.0008 0.0020 0.70 0.0276 0.20 0.0079 0.23 0.30 0.0071 0.0091 0.0118 3.00 0.1181 2.38 2.48 0.0878 0.0937 0.0976 3.00 0.1181 1.64 1.74 0.0587 0.0646 0.0685 0.50 0.0197 ...
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... Order codes 7 Order codes Table 5. Order codes Order codes L6928D L6928D013TR L6928Q1 L6928Q1TR 14/16 Package MSOP8 MSOP8 Tape and reel VFQFPN8 VFQFPN8 Tape and reel L6928 Packaging Tube Tube ...
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... L6928 8 Revision history Table 6. Revision history Date Revision Oct-2004 Feb-2005 Nov-2005 27-Oct-2006 22-Aug-2007 1 First Issue. 2 Changed from Product Preview to Final datasheet. 3 Updated Table 5. Electrical characteristics. Added VFQFPN8 package and new part numbers. Added R for VFQFPN8 in 4 thJA 5 Updated Table 5: Order codes on page 14 ...
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... 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 16/16 Please Read Carefully: © 2007 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com L6928 ...