MIC4416 Micrel MIC4416/4417 IttyBitty™ Low-Side MOSFET Driver General Description Features The MIC4416 and MIC4417 IttyBitty™ low-side MOSFET drivers are designed to switch an N-channel enhancementtype MOSFET from a TTL-compatible control signal in lowside switch applications. The MIC4416 is noninverting and the MIC4417 is inverting. These drivers feature short delays and high peak current to produce precise edges and rapid rise and fall times. Their tiny 4-lead SOT-143 package uses minimum space. The MIC4416/7 is powered from a +4.5V to +18V supply voltage. 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 logic-level N-channel MOSFETs. • +4.5V to +18V operation • Low steady-state supply current 50µA typical, control input low 370µA typical, control input high • 1.2A nominal peak output 3.5Ω typical output resistance at 18V supply 7.8Ω typical output resistance at 5V supply • 25mV maximum output offset from supply or ground • Operates in low-side switch circuits • TTL-compatible input withstands –20V • ESD protection • Inverting and noninverting versions In a low-side configuration, the driver can control a MOSFET that switches any voltage up to the rating of the MOSFET. The MIC4416 is available in the SOT-143 package and is rated for –40°C to +85°C ambient temperature range. Applications • • • • Battery conservation Solenoid and motion control Lamp control Switch-mode power supplies Ordering Information Part Number Temp. Range Package Marking –40°C to +85°C SOT-143 D10 –40°C to +85°C SOT-143 D11 Noninverting MIC4416BM4 Inverting MIC4417BM4 Typical Application Load Voltage† * Siliconix 30mΩ, 7A max. † Load voltage limited only by MOSFET drain-to-source rating MIC4416 0.1µF 3 4 On Off Load +12V 4.7µF VS G CTL GND 2 1 Si9410DY* N-channel MOSFET Low-Side Power Switch April 1998 5-23 5 MIC4416 Micrel Pin Configuration G GND 2 1 Part Identification Dxx 3 4 VS CTL Part Number Identification MIC4416BM4 D10 MIC4417BM4 D11 Early production identification: ML10 SOT-143 (M4) Pin Description Pin Number Pin Name Pin Function 1 GND 2 G Gate (Output) : Gate connection to external MOSFET. 3 VS Supply (Input): +4.5V to +18V supply. 4 CTL Control (Input): TTL-compatible on/off control input. MIC4416 only: Logic high forces the gate output to the supply voltage. Logic low forces the gate output to ground. MIC4417 only: Logic high forces the gate output to ground. Logic low forces the gate output to the supply voltage. Ground: Power return. 5-24 April 1998 MIC4416 Micrel Absolute Maximum Ratings Operating Ratings Supply Voltage (VS) .................................................... +20V Control Voltage (VCTL) .................................. –20V to +20V Gate Voltage (VG) ....................................................... +20V Junction Temperature (TJ) ........................................ 150°C Lead Temperature, Soldering ................... 260°C for 5 sec. Supply Voltage (VS) ....................................... +4.5 to +18V Ambient Temperature Range (TA) ............. –40°C to +85°C Thermal Resistance (θJA)...................................... 220°C/W (soldered to 0.25in2 copper ground plane) Electrical Characteristics Parameter Condition (Note 1) Min Supply Current 4.5V ≤ VS ≤ 18V VCTL = 0V VCTL = 5V Control Input Voltage 4.5V ≤ VS ≤ 18V VCTL for logic 0 input VCTL for logic 1 input Typ Max Units 50 370 200 1500 µA µA 0.8 V V 10 µA 2.4 Control Input Current 0V ≤ VCTL ≤ VS Delay Time, VCTL Rising VS = 5V CL = 1000pF, Note 2 42 VS = 18V CL = 1000pF, Note 2 33 VS = 5V CL = 1000pF, Note 2 42 VS = 18V CL = 1000pF, Note 2 23 VS = 5V CL = 1000pF, Note 2 24 VS = 18V CL = 1000pF, Note 2 14 VS = 5V CL = 1000pF, Note 2 28 VS = 18V CL = 1000pF, Note 2 16 Gate Output Offset Voltage 4.5V ≤ VS ≤ 18V VG = high VG = low –25 25 mV mV Output Resistance VS = 5V, IOUT = 10mA P-channel (source) MOSFET N-channel (sink) MOSFET 7.6 7.8 Ω Ω P-channel (source) MOSFET N-channel (sink) MOSFET 3.5 3.5 Delay Time, VCTL Falling Output Rise Time Output Fall Time VS = 18V, IOUT = 10mA Gate Output Reverse Current –10 No latch up 250 ns 60 ns ns 40 ns ns 40 ns ns 40 10 10 ns Ω Ω mA General Note: Devices are ESD protected, however handling precautions are recommended. Note 1: Typical values at TA = 25°C. Minimum and maximum values indicate performance at –40°C ≥ TA ≥ +85°C. Parts production tested at 25°C. Note 2: Refer to “MIC4416 Timing Definitions” and “MIC4417 Timing Definitions” diagrams (see next page). April 1998 5-25 5 MIC4416 Micrel Definitions ISUPPLY IOUT MIC4416/7 VSUPPLY 3 MIC4416 = high MIC4417 = low 4 VS CTL G GND 2 ISUPPLY VSUPPLY 3 MIC4416 = low MIC4417 = high 4 VOUT ≈ VSUPPLY 1 Source State (P-channel on, N-channel off) IOUT MIC4416/7 VS CTL G GND 2 VOUT ≈ GND 1 Sink State (P-channel off, N-channel on) MIC4416/MIC4417 Operating States INPUT 5V 90% 2.5V 10% 0V VS 90% delay time pulse width rise time delay time fall time OUTPUT 10% 0V MIC4416 (Noninverting) Timing Definitions INPUT 5V 90% 2.5V 10% 0V VS 90% delay time pulse width rise time delay time fall time OUTPUT 10% 0V MIC4417 (Inverting) Timing Definitions Test Circuit VSUPPLY MIC4416/7 3 4 VS CTL G GND 2 1 CL VOUT 5V 0V 5-26 April 1998 MIC4416 Micrel Typical Characteristics Note 3 Quiescent Supply Current vs. Supply Voltage 300 200 100 VCTL = 0V 0 1MHz 3 6 9 12 15 SUPPLY VOLTAGE (V) 100kHz 10 10kHz 1 VSUPPLY = 5V 0.1 18 1 10 CAPACITANCE (nF) 10 10kHz 1 VSUPPLY = 18V 0.1 100 Output Rise and Fall Time vs. Load Capacitance Supply Current vs. Frequency 100 10 100 VSUPPLY = 18V fCTL = 50kHz FALL 1 RISE TIME (µs) TIME (µs) 5V 10 CAPACITANCE (nF) 10 VSUPPLY = 5V fCTL = 50kHz 10 1 1 Output Rise and Fall Time vs. Load Capacitance 100 VSUPPLY = 18V 100kHz 1MHz SUPPLY CURRENT (mA) 400 SUPPLY CURRENT (mA) 100 100 VCTL = 5V SUPPLY CURRENT (mA) SUPPLY CURRENT (µA) 500 0 Supply Current vs. Load Capacitance Supply Current vs. Load Capacitance 1 FALL RISE 0.1 2000 1000 100 0.1 10 0.1 0.01 FREQUENCY (kHz) Delay Time vs. Supply Voltage 1 10 CAPACITANCE (nF) 100 0.01 Delay Time vs. Temperature 60 1 10 CAPACITANCE (nF) 100 Delay Time vs. Temperature 60 60 VCTL FALL 50 VCTL RISE 30 20 50 VCTL RISE 40 TIME (ns) 40 TIME (ns) TIME (ns) 50 30 20 40 30 20 VCTL FALL VCTL FALL 10 0 10 0 3 6 9 12 15 SUPPLY VOLTAGE (V) 10 VSUPPLY = 18V 0 -60 -30 0 30 60 90 120 150 TEMPERATURE (°C) VSUPPLY = 5V 0 -60 -30 0 30 60 90 120 150 TEMPERATURE (°C) 18 Rise and Fall Time vs. Supply Voltage Rise and Fall Time vs. Temperature 50 Rise and Fall Time vs. Temperature 50 50 40 40 TIME (ns) TIME (ns) 30 FALL 10 RISE 0 April 1998 0 3 6 9 12 15 SUPPLY VOLTAGE (V) 30 RISE 20 10 18 FALL VSUPPLY = 5V fCTL = 1MHz 0 -60 -30 0 30 60 90 120 150 TEMPERATURE (°C) 5-27 TIME (ns) fCTL = 1MHz 40 20 VCTL RISE VSUPPLY = 18V fCTL = 1MHz 30 20 10 FALL RISE 0 -60 -30 0 30 60 90 120 150 TEMPERATURE (°C) 5 MIC4416 Micrel Output Voltage Drop vs. Output Source Current Output Voltage Drop vs. Output Sink Current 600 NOTE 5 VSUPPLY = 5V 600 400 18V 200 0 1000 500 800 VSUPPLY = 5V 600 400 18V 200 20 40 60 80 100 OUTPUT CURRENT (mA) 0 0 4 IOUT = 10mA 2 6 4 IOUT = 10mA 2 0 18 12 8 6 4 VSUPPLY = 18V IOUT ≈ 3mA ON-RESISTANCE (Ω) ON-RESISTANCE (Ω) 14 12 VSUPPLY = 5V IOUT ≈ 3mA 0 -60 -30 0 30 60 90 120 150 TEMPERATURE (°C) 10 5,000pF 2,000pF 1,000pF 1 0pF 0.1 1x102 1x103 1x104 1x105 1x106 1x107 FREQUENCY (Hz) 10 200 2.0 4 VSUPPLY = 18V IOUT ≈ 3mA Supply Current vs. Frequency 5-28 0 3 6 9 12 15 SUPPLY VOLTAGE (V) 18 Typical Characteristics at TA = 25°C, VS = 5V, CL = 1000pF unless noted. Note 4: Source-to-drain voltage drop across the internal P-channel MOSFET = VS – VG. Note 5: Drain-to-source voltage drop across the internal N-channel MOSFET = VG – VGND. (Voltage applied to G.) Note 6: 1µs pulse test, 50% duty cycle. OUT connected to GND. OUT sources current. (MIC4416, VCTL = 5V; MIC4417, VCTL = 0V) Note 7: 1µs pulse test, 50% duty cycle. VS connected to OUT. OUT sinks current. (MIC4416, VCTL = 0V; MIC4417, VCTL = 5V) 0pF 0.1 1x102 1x103 1x104 1x105 1x106 1x107 FREQUENCY (Hz) Sink NOTE 7 Note 3: 2,000pF 1,000pF 1.0 0 5,000pF 10 Source NOTE 6 1.5 0.5 VSUPPLY = 18V CL = 10,000pF Peak Output Current vs. Supply Voltage 2.5 6 2 5V 0 -60 -30 0 30 60 90 120 150 TEMPERATURE (°C) 8 1 18 VSUPPLY = 18V 400 18 VSUPPLY = 5V IOUT ≈ 3mA 100 SUPPLY CURRENT (mA) SUPPLY CURRENT (mA) CL = 10,000pF 3 6 9 12 15 SUPPLY VOLTAGE (V) 0 -60 -30 0 30 60 90 120 150 TEMPERATURE (°C) Supply Current vs. Frequency VSUPPLY = 5V 0 600 Output Sink Resistance vs. Temperature 14 3 6 9 12 15 SUPPLY VOLTAGE (V) 800 8 Output Source Resistance vs. Temperature 2 0 Control Input Hysteresis vs. Temperature CURRENT (A) 6 100 0 HYSTERESIS (mV) ON RESISTANCE (Ω) ON RESISTANCE (Ω) 8 10 200 20 40 60 80 100 OUTPUT CURRENT (mA) 10 3 6 9 12 15 SUPPLY VOLTAGE (V) 300 Output Sink Resistance 10 0 400 100 Output Source Resistance 0 HYSTERESIS (mV) 800 0 Control Input Hysteresis vs. Supply Voltage 1200 NOTE 4 1000 VOLTAGE DROP (mV) VOLTAGE DROP (mV) 1200 April 1998 MIC4416 Micrel Functional Diagram VSUPPLY VSWITCHED VS D1 MIC4417 INVERTING CTL Logic-Level Input Q2 D4 Load 0.6mA 0.3mA Q3 R1 2k G Q1 D2 D3 35V D5 MIC4416 NONINVERTING Q4 GND Functional Diagram with External Components 5 Functional Description Refer to the functional diagram. The MIC4416 is a noninverting driver. A logic high on the CTL (control) input produces gate drive output. The MIC4417 is an inverting driver. A logic low on the CTL (control) input produces gate drive output. The G (gate) output is used to turn on an external N-channel MOSFET. Supply VS (supply) is rated for +4.5V to +18V. External capacitors are recommended to decouple noise. Control CTL (control) is a TTL-compatible input. CTL 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 CTL is rising, is slightly higher than the control threshold voltage when CTL is falling. When CTL is low, Q2 is on, which applies the additional 0.6mA current source to Q1. Forcing CTL 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 threshold. April 1998 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 noninverting versions. The last inverter functions as a driver for the output MOSFETs Q3 and Q4. Gate Output G (gate) is designed to drive a capacitive load. VG (gate output voltage) is either approximately the supply voltage or approximately ground, depending on the logic state applied to CTL. If CTL is high, and VS (supply) drops to zero, the gate output will be floating (unpredictable). ESD Protection D1 protects VS from negative ESD voltages. D2 and D3 clamp positive and negative ESD voltages applied to CTL. R1 isolates the gate of Q1 from sudden changes on the CTL input. D4 and D5 prevent Q1’s gate voltage from exceeding the supply voltage or going below ground. 5-29 MIC4416 Micrel +15V Application Information * Gate enhancement voltage The MIC4416/7 is designed to provide high peak current for charging and discharging capacitive loads. The 1.2A 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 MIC4416/7 is not designed to directly switch 1.2A continuous loads. Supply Bypass 3 4 Logic Input CTL Load Standard MOSFET IRFZ24† 2 G 1 GND VGS* 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 have an absolute maximum gate-to-source voltage of ±10V. They are less common and generally more expensive. The MIC4416/7 can drive a logic-level MOSFET if the supply voltage, including transients, does not exceed the maximum MOSFET gate-to-source rating (10V). +5V * Gate enhancement voltage (must not exceed 10V) +4.5V to 10V* 4.7µF MIC4416 0.1µF 3 4 Logic Input VS CTL Logic-Level MOSFET IRLZ44† 2 G 1 GND Try a 3Ω, 10W or 100Ω, 1/4W resistor VGS* † International Rectifier 28mΩ, 60V MOSFET Figure 2. Using a Logic-Level MOSFET At low voltages, the MIC4416/7’s internal P- and N-channel MOSFET’s on-resistance will increase and slow the output rise time. Refer to “Typical Characteristics” graphs. Inductive Loads VSWITCHED VSUPPLY Schottky Diode 4.7µF 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. MOSFET Selection 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 MIC4416/7’s on-state output is approximately equal to the supply voltage. The lowest usable voltage depends upon the behavior of the MOSFET. VS † International Rectifier 100mΩ, 60V MOSFET 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—resulting 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 VS 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. Try a 15Ω, 15W or 1k, 1/4W resistor MIC4416 0.1µF Load Capacitors from VS to GND are recommended to control switching and supply transients. Load current and supply lead length are some of the factors that affect capacitor size requirements. A 4.7µF or 10µF 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 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 tantalum capacitors without additional current limiting. Normal power supply turn-on (slow rise time) or printed circuit trace resistance is usually adequate for normal product usage. +8V to +18V 4.7µF MIC4416 0.1µF 3 4 On Off VS CTL G GND 2 1 Figure 3. Switching an Inductive Load 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-to-source ratings, a Schottky diode should be connected across the inductive load. 5-30 April 1998 MIC4416 Micrel 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 (switchmode 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 VS to GND through both internal MOSFETs. Power dissipation is the product of supply voltage and supply current: High-Frequency Operation Although the MIC4416/7 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 MIC4416/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. 4.7µF 3 PD = power dissipation (W) VS = supply voltage (V) IS = supply current (A) [see paragraph below] 2) PD ≤ Logic Input 150 − TA 220 GND 2 1 G S Logic-Level MOSFET IRL3103* 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. TA = ambient temperature (°C) [68°F = 20°C] 220 = package thermal resistance (°C/W) Maximum power dissipation at 20°C with the driver soldered to a 0.25in2 ground plane is approximately 600mW. PCB heat sink/ ground plane GND CTL PCB traces Figure 4. Heat-Sink Plane The SOT-143 package θJA (junction-to-ambient thermal resistance) can be improved by using a heat sink larger than the specified 0.25in2 ground plane. Significant heat transfer occurs through the large (GND) lead. This lead is an extension of the paddle to which the die is attached. April 1998 CTL D G Figure 5. MOSFET Capacitance Effects at High Switching Frequency PD (max) = maximum power dissipation (W) 150 = absolute maximum junction temperature (°C) VS 4 VS * International Rectifier 14mΩ, 30V MOSFET, logic-level, VGS = ±20V max. where: G MIC4416 0.1µF TJ (junction temperature) is the sum of TA (ambient temperature) and the temperature rise across the thermal resistance of the package. In another form: Compare 47kΩ, 5W to 1kΩ, 1/4W loads +4.5V to 18V 1) PD = VS × IS where: Supply current is a function of supply voltage, switching 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), below. +5V Slower rise time observed at MOSFET’s drain 5-31 5