L6935 STMicroelectronics, L6935 Datasheet
L6935
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L6935 Summary of contents
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... L6935 TR May 2008 High performance 3 A ULDO linear regulator Description L6935 is an ultra low drop output linear regulator operating input and is able to support output current Designed with an internal low-R be used for on-board DC-DC conversions saving in real estate, list of components and power dissipation ...
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... Typical performances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5 Device description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.1 Soft-start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.2 Power Good . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.3 VIN vs VBIAS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.4 Protections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.4.1 5.4.2 6 Application information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 6.1 Components selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 6.1.1 6.1.2 6.2 VIN, VBIAS and sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 7 Demonstration board description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 8 VFQFPN20 mechanical data and package dimensions . . . . . . . . . . . . 18 9 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2/20 Over-current protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Thermal protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Input capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Output capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 L6935 ...
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... Typical application circuit and block diagram 1.1 Application circuit Figure 1. Typical application circuit - VIN L6935 Reference Schematic Figure 2. Typical application circuit - VIN V BIAS V = 0.75V BIAS EN L6935 Reference Schematic (*) Vin may decrease until the minimum drop is reached. Conversely, Vout can rise untile the minimum drop is reached. ...
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... Typical application circuit and block diagram 1.2 Block diagram Figure 3. Block diagram VIN VBIAS SS EN ENABLE GND 4/20 CHARGE PUMP VREF + REFERENCE 0.500V - ERROR AMPLIFIER THERMAL SENSOR 0.9 VREF CURRENT LIMIT DRIVER + - L6935 VOUT ADJ PGOOD ...
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... Filter to GND with capacitor larger than the one used for V Not internally connected. Regulated output voltage. This pin is connected to the source of the internal N-mos. MLCC capacitor are supported. Filter to GND with capacitor smaller than the one used for V L6935 PGOOD N.C. N.C. GND N ...
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... V and 3.0 V. Soft-start pin. The soft-start time is programmed connecting an external capacitor C from this pin to GND steady state regulation, the voltage at this pin is 3.3 V. Ground connection. Connect to PCB GND Plane with enough VIAs to improve thermal conductivity. L6935 , it is possible to OUT ...
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... MAX T Storage temperature range STG T Junction temperature range J 1. Measured with the component mounted on demonstration board in free air ( layer 70 µm copper). 7/20 Parameter to GND to GND to GND to GND Parameter (1) L6935 Value Unit 5 -0.3 to 3 ±1000 V Value Unit 55 °C/W 150 ° ...
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... Vin = 3 100 100...120 Hz Vin = 3 V; ∆Vin = 2 Vpp; Vout = 1 falling, wrt Ref. ADJ rising Vss = 0 V (1) Temperature rising (1) Hysteresis L6935 Min Typ Max Unit 5 BIAS 1.275 V 2 µ ...
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... Temperature [° 100 120 140 Temperature [°C] VBIAS = VIN, VOUT = 0.5V 2.5 3.0 3.5 4.0 4.5 5.0 V [V] IN 4.0 3.8 3.6 3.4 3.2 3.0 -40 - Temperature [° VIN VIN -40 - 100 Temperature [°C] 0.2% VBIAS = 1.4V, VOUT = 2V 0.1% 0.0% -0.1% -0.2% 2.0 2.5 3.0 3.5 4.0 V [V] IN L6935 100 120 140 120 140 4.5 5.0 ...
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... Typical performances Figure 8. Load regulation 0.3% VBIAS = 1.4V, VIN = 2.6V, VOUT = 2V 0.2% 0.1% 0.0% -0.1% -0.2% -0.3% 0.0 0.5 10/20 0.3% 0.2% 0.1% 0.0% -0.1% -0.2% -0.3% 1.0 1.5 2.0 2.5 Output Current [A] VBIAS = VIN = 1.4V, VOUT = 0.5V 0.0 0.5 1.0 1.5 2.0 Output Current [A] L6935 2.5 ...
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... Device description 5 Device description 5.1 Soft-start L6935 implements a soft-start feature to smoothly charge the output filter avoiding high in- rush currents to be required to the input power supply. The soft-start process begins as soon constant current I capacitor ( this pin a voltage ramp is implemented; the voltage ramp internally SS clamps the E ...
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... 5.4 Protections L6935 is equipped with a set of protections in order to protect both the load and the device from electrical overstress. Each protection does not latch the device, that returns to work properly as the perturbation disappear. 5.4.1 Over-current protection An over current protection is provided: if the current that flows through the power DMOS is greater than 3 ...
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... The device constantly monitors its internal temperature. As the silicon reaches a 150 °C, the control circuit turns off the power DMOS, and stays off until a safe temperature of 150° - 20° = 130 °C. Figure 12. Over-temperature protection 13/20 Figure 12 shows how the over-temperature protection intervention. L6935 ...
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... Application information 6 Application information L6935 is the best choice in smart linear regulator applications, due to its own small size, high power delivered and high regulation accuracy. Furthermore thermal shut-down and OCP guarantee the highest reliability for each application. V can be separated < resulting in a better performance. In fact, the power dissipated decreases as ...
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... ADJ ≠ VIN VBIAS VIN VOUT L6935 PGOOD EN SS GND PAD needs to be connected to the Last-Coming rail between VCC and VIN. EH VOUT = 0. OUT PGOOD R 2 VOUT = 0. OUT ADJ PGOOD R 2 L6935 ...
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... Demonstration board description 7 Demonstration board description Figure 15 and Figure 16 designed for L6935. V mounted. C3 defines the Soft-Start timer, according to the relationship described in the Section 5.1. The value of the output divider R V value, according to the following equation: OUT Figure 15. Demonstration board schematic V BIAS ...
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... OUT 0.75 V OUT 1.00 V OUT 1.25 V OUT 1.50 V OUT 3.00 V OUT DC Table 7. L6935 demonstration board bill of material Reference C1 17/20 are available in order to program the value Ω kΩ kΩ kΩ ...
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... PACKAGE AND PACKING INFORMATION Very Fine Quad Flat Package No lead Weight: not available VFQFPN20 (4x4x1.00mm) L6935 ® ...
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... Revision history 9 Revision history Table 8. Document revision history Date 20-May-2008 19/20 Revision 1 Initial release L6935 Changes ...
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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 20/20 Please Read Carefully: © 2008 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com L6935 ...