MIC4414/4415 1.5A, 4.5V to 18V, Low-Side MOSFET Driver General Description Features The MIC4414 and MIC4415 are low-side MOSFET drivers designed to switch an N-channel enhancement type MOSFET in low-side switch applications. The MIC4414 is a non-inverting driver and the MIC4415 is an inverting driver. These drivers feature short delays and high peak current to produce precise edges and rapid rise and fall times. The MIC4414/15 are powered from a 4.5V to 18V supply and can sink and source peak currents up to 1.5A, switching a 1000pF capacitor in 12ns. The on-state gate drive output voltage is approximately equal to the supply voltage (no internal regulators or clamps). High supply voltages, such as 10V, are appropriate for use with standard N-channel MOSFETs. Low supply voltages, such as 5V, are appropriate for use with many logic-level Nchannel MOSFETs. In a low-side configuration, the driver can control a MOSFET that switches any voltage up to the rating of the MOSFET. The MIC4414 and MIC4415 are available in an ultra-small 4-pin 1.2mm x 1.2mm thin QFN package and is rated for –40°C to +125°C junction temperature range. Data sheets and support documentation can be found on Micrel’s web site at: www.micrel.com. Ultra-small 4-pin 1.2mm x 1.2mm thin QFN package +4.5V to +18V operating supply voltage range 1.5A peak current – 3.5Ω output resistance at 18V – 9Ω output resistance at 5V Low steady-state supply current – 77µA control input low – 445µA control input high 12ns rise and fall times into 1000pF load MIC4414 (non-inverting) MIC4415 (inverting) -40°C to +125°C junction temperature range Applications Switch mode power supplies Solenoid drivers Motor driver _________________________________________________________________________________________________________________________ Typical Application Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com August 2012 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Ordering Information Part Number Marking Configuration Package Junction Temperature Range Lead Finish MIC4414YFT D9 Non-Inverting 4-pin 1.2mm x 1.2mm Thin QFN -40°C to +125°C Pb-Free MIC4415YFT D8 Inverting 4-pin 1.2mm x 1.2mm Thin QFN -40°C to +125°C Pb-Free Note: 1.Thin QFN pin 1 identifier = “▲” Pin Configuration 1.2mm x 1.2mm Thin QFN (Top View) Pin Description Pin Number Pin Name Pin Function 1 OUT Gate Output: Connection to gate of external MOSFET. 2 GND Ground. Control Input: 3 IN MIC4414: Logic high drives the gate output above the supply voltage. Logic low forces the gate output near ground. Do not leave floating. MIC4415: Logic low drives the gate output above the supply voltage. Logic high forces the gate output near ground. Do not leave floating. 4 August 2012 VDD Supply Voltage: +4.5V to +18V supply. 2 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Absolute Maximum Ratings(1) Operating Ratings(3) VDD to GND.................................................................+20V IN to GND....................................................... –20V to +20V OUT to GND.................................................................+20V Junction Temperature (TJ) ........................–55°C to +150°C Storage Temperature (Ts).........................–55°C to +165°C ESD Rating(2) ................................................. ESD Sensitive VDD to GND.................................................. +4.5V to +18V IN to GND........................................................... 0V to VDD Junction Temperature (TJ) ...................... .40C to +125C Thermal Resistance 1.2mm x 1.2mm Thin QFN (JC) ........................60°C/W 1.2mm x 1.2mm Thin QFN (JA) ......................140°C/W Electrical Characteristics(4) 4.5V VDD 18V, CL = 1000pF; TA = 25°C, Bold values indicate 40°C ≤ TJ ≤ +125°C. Parameter Condition Min MIC4414: IN = 0V, VDD = 18V Supply Current MIC4415: IN = 5V, VDD = 18V IN Current Output Rise Time Output Fall Time Delay Time, IN Rising Delay Time, IN Falling Output Offset Voltage Max 77 200 445 IN = Logic High 3 0V VIN VDD -10 +10 30 VDD = 18V, CL = 1000pF 12 VDD = 5V, CL = 1000pF 33 VDD = 18V, CL = 1000pF 12 VDD = 5V, CL = 1000pF 52 VDD = 18V, CL = 1000pF 29 VDD = 5V, CL = 1000pF 58 VDD = 18V, CL = 1000pF 30 OUT = High -25 OUT = Low 25 VDD = 18V, IOUT = 10mA Source 9 Sink 9 ns ns ns mV 3.5 10 Sink 3.5 10 250 µA ns Source Output Reverse Current V V VDD = 5V, CL = 1000pF Output Resistance 1500 0.8 IN = Logic Low VDD = 5V, IOUT = 10mA Units µA MIC4414: IN = 5V, VDD = 18V MIC4415: IN = 0V, VDD = 18V IN Voltage Typ Ω mA Notes: 1. Exceeding the absolute maximum rating may damage the device. 2. Devices are ESD sensitive. Handling precautions are recommended. Human body model, 1.5kΩ in series with 100pF. 3. The device is not guaranteed to function outside operating range. 4. Specification for packaged product only. August 2012 3 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Timing Diagram Source State Sink State (P-Channel On, N-Channel Off) (P-Channel Off, N-Channel On) MIC4414/MIC4415 Operating States MIC4414 (Non-Inverting) MIC4415 (Inverting) August 2012 4 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Typical Characteristics MIC4414 ON IN=5V, OFF IN=0V. MIC4415 ON IN=0V, OFF IN=5V. IN Bias Current vs. Supply Voltage Supply Current vs. Supply Voltage 15 400 IN = ON 300 200 100 IN = OFF 0 0.8 0.6 0.4 IN = ON 6 9 12 15 18 3 SUPPLY VOLTAGE (V) 6 6 9 12 15 0 18 3 Rise and Fall Time vs. Supply Voltage 15 60 12 48 TIME (ns) 6 9 12 15 18 15 18 Delay Time vs. Supply Voltage 80 CL =1000pF IN = 1MHz, 50% DUTY CYCLE IOUT = 10mA 9 6 SUPPLY VOLTAGE (V) SUPPLY VOLTAGE (V) Output Sink Resistance vs. Supply Voltage 36 FALL 24 64 IN FALL 48 32 IN RISE RISE 16 12 3 0 0 0 0 3 6 9 12 15 0 18 3 SUPPLY VOLTAGE (V) 6 9 12 15 SUPPLY CURRENT (µA) 1.8 SOURCE SINK 0.0 0 3 6 9 12 SUPPLY VOLTAGE (V) August 2012 15 18 9 12 Output Source Resistance vs. Temperature 500 2.4 6 SUPPLY VOLTAGE (V) Supply Current vs. Temperature 3.0 0.6 3 SUPPLY VOLTAGE (V) Peak Output Current vs. Supply Voltage 1.2 0 18 14 12 400 ON-RESISTANCE (Ω) ON RESISTANCE (Ω) IOUT = 10mA 9 0 0 DELAY TIME (ns) 3 12 3 0.2 0 0 CURRENT (A) ON RESISTANCE (Ω) 1 IN BIAS CURRENT (µA) SUPPLY CURRENT (µA) 500 Output Source Resistance vs. Supply Voltage VDD = 5V IOUT = 3mA 10 300 VDD = 5V, IN = ON VDD = 18V, IN = ON 200 VDD = 5V, IN = OFF VDD = 18V, IN = OFF 100 8 VDD = 18V IOUT = 3mA 6 4 2 0 0 -50 -25 0 25 50 75 TEMPERATURE (°C) 5 100 125 -50 -25 0 25 50 75 100 125 TEMPERATURE (°C) M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Typical Characteristics (Continued) MIC4414 ON IN=5V, OFF IN=0V. MIC4415 ON IN=0V, OFF IN=5V. Output Sink Resistance vs. Temperature Rise and Fall Time vs. Temperature 12 50 50 45 45 FALL 35 8 VDD = 18V IOUT = 3mA 6 30 25 20 5 0 0 25 50 75 100 -25 TEMPERATURE (°C) 80 80 70 70 60 60 IN FALL TIME (ns) 50 75 100 125 -50 50 IN RISE 30 IN FALL 30 20 10 VDD = 5V IN RISE VDD = 18V 0 -20 10 40 70 100 130 Supply Current vs. Load Capacitance 100 -20 10 40 70 100 130 TIME (µs) 1 0.1 10 CAPACITANCE (nF) August 2012 VDD = 5V DUTY CYCLE = 50% 10 100 100 Output Rise and Fall Time vs. Load Capacitance 100 VDD = 18V IN = 1kHz; 50% DUTY CYCLE 10 1 FALL 1 FALL RISE 0.1 0.01 1 IN = 10kHz 1 CAPACITANCE (nF) VDD = 5V IN = 1kHz, 50% DUTY CYCLE 0.1 VDD = 18V Duty Cycle = 50% 125 IN = 100kHz 1 10 IN = 10kHz 100 10 Output Rise and Fall Time vs. Load Capacitance IN = 100kHz 10 75 IN = 1MHz TEMPERATURE (°C) IN = 1MHz 50 0.1 -50 TEMPERATURE (°C) 100 25 100 40 10 0 Supply Current vs. Load Capacitance 50 20 -50 -25 TEMPERATURE (°C) TIME (µs) TIME (ns) 25 Delay Time vs. Temperature 0 SUPPLY CURRENT (mA) 0 TEMPERATURE (°C) Delay Time vs. Temperature 40 RISE 0 -50 125 FALL 5 SUPPLY CURRENT (mA) -25 25 10 0 -50 30 15 VDD = 5V IN = 1MHz, 50% DUTY CYCLE CL =1000pF 10 2 35 20 RISE 15 4 VDD = 18V IN = 1MHz, 50% DUTY CYCLE CL =1000pF 40 TIME (ns) 40 VDD = 5V IOUT = 3mA 10 TIME (ns) ON-RESISTANCE (Ω) 14 Rise and Fall Time vs. Temperature RISE 0.01 1 10 CAPACITANCE (nF) 6 100 1 10 100 CAPACITANCE (nF) M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Typical Characteristics (Continued) MIC4414 ON IN=5V, OFF IN=0V. MIC4415 ON IN=0V, OFF IN=5V. VDD Supply Current vs. Frequency VDD Supply Current vs. Frequency 100 VDD = 5V VDD SUPPLY CURRENT (mA) VDD SUPPLY CURRENT (mA) 100 CL = 10000pF CL = 5000pF 10 CL = 1000pF CL = 0pF 0.1 CL = 10000pF CL = 5000pF 10 CL = 2000pF 1 VDD = 18V CL = 2000pF CL = 1000pF CL = 0pF 1 0.1 0 1 10 100 1000 IN FREQUENCY (kHz) August 2012 10000 0 1 10 100 1000 10000 IN FREQUENCY (kHz) 7 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Functional Diagram Functional Description The MIC4414 is a non-inverting driver. A logic high on the IN (control) pin produces gate drive output. The MIC4415 is an inverting driver. A logic low on the IN (control) pin produces gate drive output. The OUT is used to turn on an external N-channel MOSFET. The OUT pin will be driven to 0V or VDD depending on the status of IN pin. VDD VDD (supply) is rated for +4.5V to +18V. External capacitors are recommended to decouple noise. IN IN must be forced high or low by an external signal. A floating input will cause unpredictable operation. A high input turns on Q1, which sinks the output of the 0.3mA and the 0.6mA current source, forcing the input of the first inverter low. Hysteresis The control threshold voltage, when IN is rising, is slightly higher than the control threshold voltage when IN is falling. When IN is low, Q2 is on, which applies the additional 0.6mA current source to Q1. Forcing IN high turns on Q1 which must sink 0.9mA from the two current sources. The higher current through Q1 causes a larger drain-to-source voltage drop across Q1. A slightly higher control voltage is required to pull the input of the first inverter down to its August 2012 threshold. Q2 turns off after the first inverter output goes high. This reduces the current through Q1 to 0.3mA. The lower current reduces the drain-to-source voltage drop across Q1. A slightly lower control voltage will pull the input of the first inverter up to its threshold. Drivers The second (optional) inverter permits the driver to be manufactured in inverting and non-inverting versions. The last inverter functions as a driver for the output MOSFETs Q3 and Q4. OUT OUT is designed to drive a capacitive load. The OUT voltage is either approximately the supply voltage or approximately ground, depending on the logic state applied to IN. If IN is high, and VDD (supply) drops to zero, the gate output will be floating (unpredictable). ESD Protection D1 protects VDD from negative ESD voltages. D2 and D3 clamp positive and negative ESD voltages applied to IN. R1 isolates the gate of Q1 from sudden changes on the IN pin. D4 and D5 prevent Q1’s gate voltage from exceeding the supply voltage or going below ground. 8 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Application Information MOSFET Selection The MIC4414 and MIC4415 are designed to provide high peak current for charging and discharging capacitive loads. The 1.5A peak value is a nominal value determined under specific conditions. This nominal value is used to compare its relative size to other low-side MOSFET drivers. The MIC4414 and MIC4415 are not designed to directly switch 1.5A continuous loads. Standard MOSFET A standard N-channel power MOSFET is fully enhanced with a gate-to-source voltage of approximately 10V and has an absolute maximum gate-to-source voltage of ±20V. The MIC4414/15’s on-state output is approximately equal to the supply voltage. The lowest usable voltage depends upon the behavior of the MOSFET. Supply Bypass A capacitor from VDD to GND is recommended to control switching and supply transients. Load current and supply lead length are some of the factors that affect capacitor size requirements. 4.7µF or 10µF ceramic or tantalum capacitor is suitable for many applications. Low-ESR (equivalent series resistance) metalized film capacitors may also be suitable. An additional 0.1µF ceramic capacitor is suggested in parallel with the larger capacitor to control high-frequency transients. The low ESR (equivalent series resistance) of ceramic and tantalum capacitors makes them especially effective, but also makes them susceptible to uncontrolled inrush current from low impedance voltage sources (such as NiCd batteries or automatic test equipment). Avoid instantaneously applying voltage, capable of very high peak current, directly to or near low ESR capacitors without additional current limiting. Normal power supply turn-on (slow rise time) or printed circuit trace resistance is usually adequate. Figure 1. Using a Standard MOSFET Logic-Level MOSFET Logic-level N-channel power MOSFETs are fully enhanced with a gate-to-source voltage of approximately 5V and some of them have an absolute maximum gateto-source voltage of ±10V. They are less common and generally more expensive. The MIC4414/15 can drive a logic-level MOSFET if the supply voltage, including transients, does not exceed the maximum MOSFET gate-to-source rating (10V). Circuit Layout Avoid long power supply and ground traces. They exhibit inductance that can cause voltage transients (inductive kick). Even with resistive loads, inductive transients can sometimes exceed the ratings of the MOSFET and the driver. When a load is switched off, supply lead inductance forces current to continue flowing and results in a positive voltage spike. Inductance in the ground (return) lead to the supply has similar effects, except the voltage spike is negative. Switching transitions momentarily draw current from VDD to GND. This combines with supply lead inductance to create voltage transients at turn on and turnoff. Transients can also result in slower apparent rise or fall times when driver’s ground shifts with respect to the control input. Minimize the length of supply and ground traces or use ground and power planes when possible. Bypass capacitors should be placed as close as practical to the driver. Figure 2. Using a Logic-Level MOSFET August 2012 9 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 frequency, and load capacitance. Determine this value from the “Typical Characteristics: Supply Current vs. Frequency” graph or measure it in the actual application. Do not allow PD to exceed PD (MAX), as shown in the Eq 2. TJ (junction temperature) is the sum of TA (ambient temperature) and the temperature rise across the thermal resistance of the package. In another form: At low voltages, the MIC4414/15’s internal P- and Nchannel MOSFET’s on-resistance will increase and slow the output rise time. Refer to “Typical Characteristics” graphs. Inductive Loads Switching off an inductive load in a low-side application forces the MOSFET drain higher than the supply voltage (as the inductor resists changes to current). To prevent exceeding the MOSFET’s drain-to-gate and drain-tosource ratings, a Schottky diode should be connected across the inductive load. P (MAX) D 125 T 140 A Equation 2 where: PD (MAX) = maximum power dissipation (W) 125 = Operating maximum junction temperature (˚C) TA = ambient temperature (˚C) 140 = package thermal resistance (˚C/W) High-Frequency Operation Although the MIC4414/15 driver will operate at frequencies greater than 1MHz, the MOSFET’s capacitance and the load will affect the output waveform (at the MOSFET’s drain). For example, an MIC4414/IRL3103 test circuit using a 47Ω, 5W load resistor will produce an output waveform that closely matches the input signal shape up to about 500kHz. The same test circuit with a 1kΩ load resistor operates only up to about 25kHz before the MOSFET source waveform shows significant change. Figure 3. Switching an Inductive Load Power Dissipation The maximum power dissipation must not be exceeded to prevent die meltdown or deterioration. Power dissipation in on/off switch applications is negligible. Fast repetitive switching applications, such as SMPS (switch mode power supplies), cause a significant increase in power dissipation with frequency. Power is dissipated each time current passes through the internal output MOSFETs when charging or discharging the external MOSFET. Power is also dissipated during each transition when some current momentarily passes from VDD to GND through both internal MOSFETs. Power dissipation is the product of supply voltage and supply current: PD VDD IDD Equation 1 where: Figure 4. MOSFET Capacitance Effects at High Switching Frequency PD = Power dissipation (W) VDD = Supply voltage (V) IDD = Supply current (A) Supply current is a function of supply voltage, switching August 2012 10 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 When the MOSFET is driven off, the slower rise occurs because the MOSFET’s output capacitance recharges through the load resistance (RC circuit). A lower load resistance allows the output to rise faster. For the fastest driver operation, choose the smallest power MOSFET that will safely handle the desired voltage, current, and safety margin. The smallest MOSFETs generally have the lowest capacitance. August 2012 11 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Evaluation Board Schematic Bill of Materials Item C1 Part Number GRM188R71E104KA01D C2 Manufacturer (1) Murata C2012X5R1E475K TDK(2) GRM21BR61E475KA12L Murata 08053D475KAT2A Description Qty. 0.1µF/25V Ceramic Capacitor, X7R, Size 0603 1 4.7µF/25V Ceramic Capacitor, X5R, Size 0805 1 (3) AVX C3 (OPEN) Used as gate Capacitor, different values Q1 (OPEN) MIC4414YFT U1 MIC4415YFT Micrel, Inc.(4) 1.5A/4.5V to 18V Low Side MOSFET Driver 1 Notes: 1. Murata: www.murata.com. 2. TDK: www.tdk.com. 3. AVX: www.avx.com. 4. Micrel, Inc.: www.micrel.com. August 2012 12 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 PCB Layout Figure 5. MIC4414/15 Evaluation Board Top Layer Figure 6. MIC4414/15 Evaluation Board Bottom Layer August 2012 13 M9999-080112-A Micrel, Inc. MIC4414/MIC4415 Package Information 4-Pin 1.2mm x 1.2mm Thin QFN (FT) 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. © 2012 Micrel, Incorporated. August 2012 14 M9999-080112-A