MIC4950 Hyper Speed Control™ 5A Buck Regulator General Description The MIC4950 is a high-efficiency, 5A synchronous buck regulator with ultra-fast transient response. It is perfectly suited for supplying processor core and I/O voltages from a 5V or 3.3V bus. The MIC4950 provides a switching frequency up to 3.3MHz while achieving peak efficiencies up to 95%. An additional benefit of high-frequency operation is very low output ripple voltage throughout the entire load range with the use of a small output capacitor. The MIC4950 is designed for use with a very small inductor, down to 1µH, and an output ceramic capacitor as small as 10µF, without the need for external ripple injection. A wide range of output capacitor types and values can also be accommodated. The MIC4950 supports safe start-up into a pre-biased output, and offers short-circuit and thermal shutdown protections. The MIC4950 is available in 8-Pin SOIC and 10-Pin 3mm × 4mm DFN packages with an operating junction temperature range from –40°C to +125°C. Datasheets and support documentation are available on Micrel’s web site at: www.micrel.com. Features Input voltage: 2.7V to 5.5V 5A output current Up to 95% efficiency Up to 3.3MHz operation Safe start-up into a pre-biased output Power Good output Ultra-fast transient response Low output voltage ripple Low RDSON integrated MOSFET switches 0.01µA shutdown current Thermal shutdown and current limit protection Output voltage as low as 0.7V 8-Pin SOIC and 3mm × 4mm DFN-10L –40°C to +125°C junction temperature range Applications DTVs Set-top boxes Printers DVD players Distributed power supplies Typical Application Hyper Speed Control is a trademark of Micrel, Inc. Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com March 20, 2014 Revision 1.1 Micrel, Inc. MIC4950 Ordering Information Part Number (1) MIC4950YFM MIC4950YFL Top Mark Temperature Range Package 4950YFM –40°C ≤ TJ ≤ +125°C 8-pin SOIC –40°C ≤ TJ ≤ +125°C MIC4950 10-pin 3mm x 4mm DFN Lead Finish Pb-Free (2) Pb-Free Note: 1. Other options are available. Contact Micrel for details. 2. DFN is GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free. Pin Configuration 8-Pin SOIC (FM) (Top View) 3mm x 4mm DFN (FL) (Top View) Pin Description Pin Number SOIC-8 (YFM) Pin Number DFN-10 (YFL) Pin Name 1 1, 2, EP PGND Power Ground. 2 3, 8 PVIN Power Input Voltage: Connect a 10µF ceramic capacitor between PVIN and PGND for input decoupling. Pins 3 and 8 are internally connected in the DFN-10 package. 3 4 AVIN Analog Input Voltage: Connect a 1µF ceramic capacitor between AVIN and AGND to decouple the noise from the internal reference and error comparator. 4 5 AGND Analog Ground Input: Connect to a quiet ground plane for best operation. Do not route power switching currents on the AGND net. Connect AGND and PGND nets together at a single point. 5 6 FB Feedback (Input): Connect an external divider between VOUT and AGND (Analog Ground) to program the output voltage. 6 7 PG Power Good (Output): Open-drain output. A pull-up resistor from this pin to a voltage source is required to detect an output power-is-good condition. 7 9 EN Enable (Input): Logic high enables operation of the regulator. Logic low shuts down the device. Do not leave floating. 8 10 SW Switch (Output): Internal power MOSFET output switches. March 20, 2014 Pin Function 2 Revision 1.1 Micrel, Inc. MIC4950 Absolute Maximum Ratings(3) Operating Ratings(4) PVIN, AVIN Supply Voltage (VIN) ...................... –0.3V to 6V SW Output Switch Voltage (VSW) ...................... –0.3V to VIN EN, PG (VEN, VPG) ............................................. –0.3V to VIN FB Feedback Input Voltage (VFB) ...................... –0.3V to VIN Storage Temperature Range .................... –65°C to +150°C (5) ESD Rating ........................................................ 2kV, HBM Supply Voltage (VIN) ......................................... 2.7V to 5.5V Enable Input Voltage (VEN) .................................... 0V to VIN Junction Temperature Range (T J).......–40°C ≤ TJ ≤ +125°C Thermal Resistance SOIC-8 (JA) ..................................................... 120°C/W DFN-10 (JA) ...................................................... 35°C/W Electrical Characteristics(6) VIN = VEN = 3.3V; L = 1.0µH; CIN = 10µF; COUT = 10µF; TA = 25°C, bold values indicate –40°C≤ TJ ≤ +125°C, unless noted. Symbol Parameter Condition Min. VIN Supply Voltage Range VUVLO Under-Voltage Lockout Threshold VUVLOH Under-Voltage Lockout Hysteresis IQ Quiescent Current IOUT = 0mA , FB > 1.2*VFB (Nominal) 0.8 2 mA ISD Shutdown Current VEN = 0V 0.01 2 µA VFB Feedback Voltage 0.609 0.625 0.64 V ILIMIT Current Limit 5.5 7.5 10 A LINEREG Output Voltage Line Regulation 2.7 2.41 Turn-On LOADREG FB = 0.9*VFB (Nominal) VIN = 4.5V to 5.5V if VOUTNOM ≥ 2.5V, ILOAD = 20mA 20mA < ILOAD < 500mA, VIN = 5.0V if VOUTNOM ≥ 2.5V 20mA < ILOAD < 5A, VIN = 5.0V if VOUTNOM ≥ 2.5V RDSON-N tON PWM Switch ON-Resistance Maximum Turn-On Time Units 5.5 V 2.61 V mV VIN = 2.7 to 3.5V, VOUTNOM = 1.8V, ILOAD = 20mA 20mA < ILOAD < 5A, VIN = 3.6V if VOUTNOM < 2.5V RDSON-P 2.5 Max. 400 20mA < ILOAD < 500mA, VIN = 3.6V if VOUTNOM < 2.5V Output Voltage Load Regulation Typ. 1 %/V 0.3 % 1 % ISW = 1A P-Channel MOSFET 30 ISW = –1A N-Channel MOSFET 25 VIN = 4.5V, VFB = 0.5V 665 VIN = 3.0V, VFB = 0.5V 1000 VIN = 2.7V, VFB = 0.5V 1120 Ω ns tOFF Minimum Turn-Off Time VIN = 3.0V, VFB = 0.5V 176 ns tSOFT-ON Soft Start Time VOUT = 90% of VOUTNOM 500 µs VEN Enable Threshold Turn-On 0.5 0.8 1.2 V Notes: 3. Exceeding the absolute maximum ratings may damage the device. 4. The device is not guaranteed to function outside its operating ratings. 5. Devices are ESD sensitive. Handling precautions are recommended. Human body model, 1.5kΩ in series with 100pF. 6. Specification for packaged product only. March 20, 2014 3 Revision 1.1 Micrel, Inc. MIC4950 Electrical Characteristics(6) (Continued) Symbol Parameter IEN Enable Input Current VOUTPG Power Good Threshold VOUTPGH Power Good Hysteresis TSD TSDH Condition Min. 82 Rising Typ. Max. Units 0.1 1 µA 88 94 % 7 % Overtemperature Shutdown 150 C Overtemperature Shutdown Hysteresis 20 C March 20, 2014 4 Revision 1.1 Micrel, Inc. MIC4950 Typical Characteristics Efficiency vs. Output Current 100 100 95 95 VIN = 5V VOUT = 3.3V 85 80 75 100 95 VIN = 3.3V VOUT = 1.8V 90 85 VIN = 5.0V VOUT = 1.8V 80 75 85 75 70 65 65 65 60 60 3 4 5 60 0 1 3 4 5 0 1 2 Current Limit vs. Feedback Voltage Current Limit vs. Input Voltage 12 10 10 CURRENT LIMIT (A) 12 8 6 4 4 5 Line Regulation vs. Input Voltage 3.0 8 6 4 2 VOUT = 1.8V 3 OUTPUT CURRENT (A) OUTPUT CURRENT (A) OUTPUT CURRENT (A) 2 2 LINE REGULATION (%/V) 2 VIN = 5V VOUT = 1.2V 80 70 1 VIN = 3.3V VOUT = 1.2V 90 70 0 CURRENT LIMIT (A) Efficiency vs. Output Current EFFICIENCY (%) 90 EFFICIENCY (%) EFFICIENCY (%) Efficiency vs. Output Current VIN = 5V VOUT = 1.8V 2.0 1.0 0.0 IOUT = 0A -1.0 0 0.0 0 3.0 3.5 4.0 4.5 5.0 0.3 0.4 0.5 -2.0 2.7 Line Regulation vs. Input Voltage LINE REGULATION (%/V) 1 0 VOUT = 1.8V IOUT = 0A -1 5.00 5.25 INPUT VOLTAGE (V) March 20, 2014 5.50 3.6 3 2 1 0 VOUT = 1.8V IOUT = 1A -1 -2 4.75 3.3 Line Regulation vs. Input Voltage 3 2 3.0 INPUT VOLTAGE (V) Line Regulation vs. Input Voltage 3 LINE REGULATION (%/V) 0.2 FEEDBACK VOLTAGE (V) INPUT VOLTAGE (V) -2 4.50 0.1 5.5 LINE REGULATION (%/V) 2.5 2.7 3.0 3.3 INPUT VOLTAGE (V) 5 3.6 2 1 0 VOUT = 1.8V IOUT = 1A -1 -2 4.50 4.75 5.00 5.25 5.50 INPUT VOLTAGE (V) Revision 1.1 Micrel, Inc. MIC4950 Typical Characteristics (Continued) Quiescent Current vs. Input Voltage Output Voltage (VIN = 3.3V) vs. Output Current 2.52 1.82 2 1 0 2.51 1.81 OUTPUT VOLTAGE (V) VFB > 1.2 x VFB(NOM) IOUT = 0A 3 OUTPUT VOLTAGE (V) 1.80 1.79 1.78 1.77 2.5 3.0 3.5 4.0 4.5 5.0 5.5 1 Feedback Voltage vs. Temperature SWITCHING FREQUENCY (MHz) FEEDBACK VOLTAGE (V) 0.620 0.615 VIN = 3.3V VOUT = 1.8V IOUT = 0A 0.610 0.605 -50 -20 10 40 70 100 3 4 2.48 5 0 1 2 3 4 OUTPUT CURRENT (A) Switching Frequency vs. Temperature Switching Frequency vs. Output Current 5 3.2 2.8 2.6 2.4 VIN = 3.3V VOUT = 1.8V IOUT = 0A 2.2 2.0 -50 130 -20 10 40 70 100 TEMPERATURE (°C) TEMPERATURE (°C) Switching Frequency vs. Output Current Switching Frequency vs. Output Current 130 VIN = 5.0V VOUT = 3.3V 2.8 2.4 2.0 1.6 1.2 0 1 2 3 4 5 OUTPUT CURRENT (A) 3.6 SWITCHING FREQUENCY (MHz) 3.6 SWITCHING FREQUENCY (MHz) 2 3.0 0.625 2.49 OUTPUT CURRENT (A) INPUT VOLTAGE (V) 0.630 2.50 2.46 0 0.635 VIN = 5V VOUT = 2.5V 2.47 VIN = 3.3V VOUT = 1.8V SWITCHING FREQUENCY (MHz) QUIESCENT CURRENT (mA) 4 Output Voltage (VIN = 5V) vs. Output Current 3.2 VIN = 5.0V VOUT = 1.8V 2.8 2.4 2.0 VIN = 3.3V VOUT = 1.8V 1.6 1.2 0 1 2 3 OUTPUT CURRENT (A) March 20, 2014 4 5 3.2 2.8 VIN = 5.0V VOUT = 1.2V 2.4 2.0 VIN = 3.3V VOUT = 1.2V 1.6 1.2 0 1 2 3 4 5 OUTPUT CURRENT (A) 6 Revision 1.1 Micrel, Inc. MIC4950 Functional Characteristics March 20, 2014 7 Revision 1.1 Micrel, Inc. MIC4950 Functional Characteristics (Continued) March 20, 2014 8 Revision 1.1 Micrel, Inc. MIC4950 Functional Block Diagram March 20, 2014 9 Revision 1.1 Micrel, Inc. MIC4950 PG The power-is-good (PG) pin is an open-drain output that indicates logic high when the output voltage is typically above 88% of its steady-state voltage. A pull-up resistor of 10kΩ or greater should be connected from PG to VOUT. Functional Description PVIN The power input (PVIN) pin provides power to the internal MOSFETs for the switch mode regulator section of the MIC4950. The input supply operating range is from 2.7V to 5.5V. A low-ESR ceramic capacitor of at least 10µF is required for bypass from PVIN to (Power) GND. See the “Applications Information” section for further details. FB To program the output voltage, an external resistive divider network is connected to this pin from the output voltage to AGND, as shown in the Typical Application circuit on page 1, and is compared to the internal 0.625V reference within the regulation loop. Equation 1 is used to program the output voltage: AVIN The analog power input (AVIN) pin provides power to the internal control and analog supply circuitry. Careful layout is important to ensure that high-frequency switching noise caused by PVIN is reduced before reaching AVIN. Always place a 1µF minimum ceramic capacitor very close to the IC between AVIN and AGND pins. For additional high-frequency switching noise attenuation, RC filtering can be used (R = 10Ω). R1 VOUT VREF 1 R2 Table 1 lists recommended feedback resistor values. Table 1. Recommended Feedback Resistor Values EN A logic high signal on the enable (EN) pin activates the output of the switch. A logic low on the EN pin deactivates the output and reduces the supply current to the nominal 0.01µA. Do not leave this pin floating. SW The switch (SW) pin connects directly to one side of the inductor and provides the current path during switching cycles. The other end of the inductor is connected to the load and output capacitor. Due to the high speed switching on this pin, the switch node should be routed away from sensitive nodes, whenever possible, to avoid unwanted injection of noise. VOUT R1 R2 1.0V 120kΩ 180kΩ 1.2V 274kΩ 294kΩ 1.5V 316kΩ 226kΩ 1.8V 301kΩ 160kΩ 2.5V 316kΩ 105kΩ 3.3V 309kΩ 71.5kΩ The feedforward capacitor (CF in the Typical Application schematic) is typically in the range 22pF to 39pF. The MIC4950 features an internal ripple injection network, whose current is injected into the FB node and integrated by CF, thus the waveform at FB is approximately a triangular ripple. The size of CF dictates the amount of ripple amplitude at the FB node. Smaller values of C F yield higher FB ripple amplitude and better stability, but also somewhat degrade line regulation and transient response. PGND The power ground (PGND) is the ground return terminal for the high current in the switching node SW. The current loop for the PGND should be as short as possible and kept separate from the AGND net whenever applicable. AGND The analog ground (AGND) is the ground return terminal for the biasing and control circuitry. The current loop for the signal ground should be separate from the power ground (PGND) loop. Refer to the “PCB Layout Recommendations” section for further details. March 20, 2014 Eq. 1 Hyper Speed Control™ MIC4950 uses an ON- and OFF-time proprietary ripplebased control loop, which features three different timers: 10 Minimum ON Time Maximum ON Time Minimum OFF Time Revision 1.1 Micrel, Inc. MIC4950 When the required duty cycle is very low, the required OFF time is typically far from the Minimum OFF Time limit (about 176 ns typ). In this case, the MIC4950 operates by delivering at each switching cycle a determined ON time (dependent on the input voltage). A new ON time is invoked by the error comparator when the FB voltage falls below the regulation threshold. In this mode the MIC4950 operates as an adaptive Constant-ON-Time ripple controller, with nearly constant switching frequency. Regulation takes place by controlling the valley of the FB ripple waveform. When higher duty cycles are required, regulation can no longer be maintained by decreasing the OFF time below the Minimum OFF Time limit. When this limit is reached, then the OFF Time is no longer reduced, and the MIC4950 smoothly transitions to an ON-time modulation mode. In the ON-time modulation region, frequency reduces with the increase of the required ON-time/duty cycle, and regulation finally takes place on the peak of the FB ripple waveform. Note that because of the shift of the regulation threshold between different modes, line regulation might suffer when the input voltage and/or duty cycle variations force the MIC4950 to switch form one regulation mode to the other. In applications where wide input voltage variations are expected, ensure that the line regulation is adequate for the intended application. March 20, 2014 11 Revision 1.1 Micrel, Inc. MIC4950 Also pay attention to the inductor saturation characteristic in current limit. The inductor should not heavily saturate even in current limit operation, otherwise the current might instantaneously run away and reach potentially destructive levels. Typically, ferrite-core inductors exhibit an abrupt saturation characteristic, while powdered-iron or composite inductors have a soft-saturation characteristic. Applications Information The MIC4950 is a highly efficient, 5A synchronous buck regulator ideally suited for supplying processor core and I/O voltages from a 5V or 3.3V bus. Input Capacitor A 10µF ceramic capacitor or greater should be placed close to the PVIN pin and PGND pin for bypassing. A X5R or X7R temperature rating is recommended for the input capacitor. Take into account C versus bias effect to estimate the effective capacitance and the input ripple at the VIN voltage. Peak current can be calculated in Equation 2: 1 VOUT /VIN IPEAK IOUT VOUT 2 f L Output Capacitor The MIC4950 is designed for use with a 10µF or greater ceramic output capacitor. Increasing the output capacitance will lower output ripple and improve load transient response. A low equivalent-series resistance (ESR) ceramic output capacitor is recommended based on performance, size, and cost. Ceramic capacitors with X5R or X7R temperature ratings are recommended. As shown by the calculation above, the peak inductor current is inversely proportional to the switching frequency and the inductance. The lower the switching frequency or inductance, the higher the peak current. As input voltage increases, the peak current also increases. The size of the inductor depends on the requirements of the application. Refer to the Typical Application circuit and Bill of Materials for details. Inductor Selection When selecting an inductor, it is important to consider the following factors: Inductance Rated current value Size requirements DC resistance (DCR) Core losses Eq. 2 DC resistance (DCR) is also important. While DCR is inversely proportional to size, DCR can represent a significant efficiency loss. Refer to the “Efficiency Considerations” subsection. Efficiency Considerations Efficiency is defined as the amount of useful output power, divided by the amount of power supplied (see the Typical Characteristics curves): V I Ef f iciency% OUT OUT VIN IIN The MIC4950 is designed for use with a 1µH to 2.2µH inductor. For faster transient response, a 1µH inductor will yield the best result. For lower output ripple, a 2.2µH inductor is recommended. 100 Eq. 3 There are two types of losses in switching converters: DC losses and switching losses. DC losses are simply the 2 power dissipation of I R. Power is dissipated in the highside switch during the ON cycle. Power loss is equal to the high-side MOSFET RDSON multiplied by the switch current squared. During the OFF cycle, the low-side Nchannel MOSFET conducts, also dissipating power. Device operating current also reduces efficiency. The product of the quiescent (operating) current and the supply voltage represents another DC loss. The current required to drive the gates on and off at high frequency and the switching transitions make up the switching losses. Inductor current ratings are generally given in two methods: permissible DC current, and saturation current. Permissible DC current can be rated for a 20°C to 40°C temperature rise. Saturation current can be rated for a 10% to 30% loss in inductance. Make sure that the nominal current of the application is well within the permissible DC current ratings of the inductor, also depending on the allowed temperature rise. Note that the inductor permissible DC current rating typically does not include inductor core losses. These are a very important contribution to the total inductor core loss and temperature increase in high-frequency DC-DC converters, since core losses increase with at least the square of the excitation frequency. For more accurate core loss estimation, refer to manufacturers’ datasheets or websites. When saturation current is specified, make sure that there is enough design margin, so that the peak current does not cause the inductor to enter saturation. March 20, 2014 12 Revision 1.1 Micrel, Inc. MIC4950 At the higher currents for which the MIC4950 is designed, efficiency loss is dominated by MOSFET RDSON and inductor losses. Higher input supply voltages will increase the gate-to-source threshold on the internal MOSFETs, thereby reducing the internal R DSON. This improves efficiency by reducing DC losses in the device. All but the inductor losses are inherent to the device. In this case, inductor selection becomes increasingly critical in efficiency calculations. As the inductors are reduced in size, the DC resistance (DCR) can become quite significant. The DCR losses can be calculated as in Equation 4. 2 PDCR I OUT DCR Figure 1. External Ripple Injection Eq. 4 The injected ripple is calculated using Equation 6, From that, the loss in efficiency due to inductor DCR and core losses (PCORE) can be calculated as in Equation 5. VOUT IOUT Ef f iciencyLoss (%) 1 VOUT IOUT PDCR PCORE 100 ΔVFB(pp) VIN K div D (1 - D) Eq. 5 Eq. 6 with Kdiv given by Equation 7 External Ripple Injection The MIC4950 control loop is ripple-based, and relies on an internal ripple injection network to generate enough ripple amplitude at the FB pin when negligible output voltage ripple is present. The internal ripple injection network is typically sufficient when recommended R1-R2 and CF values are used. The FB ripple amplitude should fall in the 20mV to 100mV range. K div R1//R2 R inj R1//R2 Eq. 7 and: VIN = Power stage input voltage D = VOUT/VIN = Duty cycle fSW = Switching frequency = (R1//R2//Rinj) × CF If significantly lower divider resistors and/or higher C F values are used, the amount of internal ripple injection may not be sufficient for stable operation. In this case, external ripple injection is needed. This is accomplished by connecting a series Rinj-Cinj circuit between the SW and the FB pins, as shown in Figure 1. March 20, 2014 1 fSW In Equations 6 and 7, it is assumed that the time constant associated with CF must be much greater than the switching period: 1 T 1 fSW 13 Eq. 8 Revision 1.1 Micrel, Inc. MIC4950 Evaluation Board Circuit March 20, 2014 14 Revision 1.1 Micrel, Inc. MIC4950 Bill of Materials Item C1, C2 Part Number C2012X5R1A106M125AB Manufacturer Description Qty. (7) TDK Ceramic Capacitor, 10µF, 10V, X5R, Size 0805 2 Ceramic Capacitor, 22pF, 50V, C0G, Size 0603 1 Ceramic Capacitor, 1µF, 10V, X5R, Size 0603 1 C5 DNP, Size 0603 0 C6 DNP, Size 1210 0 C7 DNP, Radial, 8mm diameter polarized capacitor 0 C3 C4 GRM219R61A106ME44 C1608C0G1H220J080AA GRM1885C1H220JA01 C1608X5R1A105M080AC GRM185R61A105ME26 RLF7030T-1R0N6R4 L1 CLF7045T-1R0N Murata (8) TDK Murata TDK Murata TDK 1µH, 6.4A, 7.3mΩ, L7.3mm x W6.8mm x H3.2mm TDK CDRH8D43RT125NP-1R0NC Sumida R1 CRCW06033013FK Vishay R2 CRCW06031603FK 1µH, 5.2A, 9.6mΩ, L7.2mm x W6.9mm x H4.5mm (9) (10) Vishay R3 1 1µH, 7.5A, 7.8mΩ, L8.5mm x W8.3mm x H4.5 mm Resistor, 301kΩ, Size 0603 1 Resistor, 160kΩ, Size 0603 1 DNP, Size 0603 0 R4 CRCW060310R0FK Vishay Resistor, 10Ω, Size 0603 1 R5 CRCW06031002FK Vishay Resistor, 10kΩ, Size 0603 1 R6 CRCW06031003FK Vishay Resistor, 100kΩ, Size 0603 1 R7 CRCW060349R9FK Vishay Resistor, 49.9Ω, Size 0603, for monitoring SW node only 1 Hyper Speed Control™ 5A Buck Regulator 1 U1 MIC4950YFL (11) Micrel, Inc. Notes: 7. TDK: www.tdk.com. 8. Murata: www.murata.com. 9. Sumida: www.sumida.com. 10. Vishay: www.vishay.com. 11. Micrel, Inc.: www.micrel.com. March 20, 2014 15 Revision 1.1 Micrel, Inc. MIC4950 PCB Layout Recommendations Top Layer Bottom Layer March 20, 2014 16 Revision 1.1 Micrel, Inc. MIC4950 Package Information and Recommended Landing Pattern(12) 8-Pin SOIC (FM) Note: 12. Package information is correct as of the publication date. For updates and most current information, go to www.micrel.com. March 20, 2014 17 Revision 1.1 Micrel, Inc. MIC4950 Package Information Recommended Landing Pattern(12) (Continued) 10-Pin DFN 3mm x 4mm (FL) MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry, specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2014 Micrel, Incorporated. March 20, 2014 18 Revision 1.1