MIC5021 Micrel, Inc. MIC5021 High-Speed High-Side MOSFET Driver General Description Features The MIC5021 high-side MOSFET driver is designed to oper- • 12V to 36V operation ate at frequencies up to 100kHz (5kHz PWM for 2% to 100% • 550ns rise/fall time driving 2000pF duty cycle) and is an ideal choice for high speed applications • TTL compatible input with internal pull-down resistor such as motor control, SMPS (switch mode power supplies), • Overcurrent limit and applications using IGBTs. The MIC5021 can also operate • Gate to source protection as a circuit breaker with or without automatic retry. • Internal charge pump A rising or falling edge on the input results in a current source • 100kHz operation guaranteed over full temperature and pulse or sink pulse on the gate output. This output current operating voltage range pulse can turn on a 2000pF MOSFET in approximately 550ns. • Compatible with current sensing MOSFETs The MIC5021 then supplies a limited current (< 2mA), if • Current source drive reduces EMI necessary, to maintain the output state. Applications An overcurrent comparator with a trip voltage of 50mV makes • Lamp control the MIC5021 ideal for use with a current sensing MOSFET. An • Heater control external low value resistor may be used instead of a sensing • Motor control MOSFET for more precise overcurrent control. An optional • Solenoid switching external capacitor placed from the C pin to ground may be T • Switch-mode power supplies used to control the current shutdown duty cycle (dead time) • Circuit breaker from 20% to < 1%. A duty cycle from 20% to about 75% is possible with an optional pull-up resistor from CT to VDD. Ordering Information The MIC5021 is available in 8-pin SOIC and plastic DIP Part Number Temperature packages. Range Package Standard Pb-Free Other members of the MIC502x family include the MIC5020 MIC5021BM MIC5021YM –40ºC to +85ºC 8-pin SOIC low-side driver and the MIC5022 half-bridge driver with a cross-conduction interlock. MIC5021BN MIC5021YN –40ºC to +85ºC 8-pin Plastic DIP Typical Application +12V to +36V MIC5021 10µF 1 8 VDD VBOOST 2 7 TTL Input Input Gate N-Channel Power MOSFET 3 6 optional* CT Sense- 2.7 4 5 nF Gnd Sense+ R SENSE 50mV R SENSE = I TRIP Load * increases time before retry High-Side Driver with Overcurrent Trip and Retry Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com July 2005 1 MIC5021

MIC5021 Micrel, Inc. Pin Configuration 1 VDD VBOOST 8 1 VDD VBOOST 8 2 Input Gate 7 2 Input Gate 7 3 CT Sense- 6 3 CT Sense- 6 4 Gnd Sense+ 5 4 Gnd Sense+ 5 DIP Package SOIC Package (N) (M) Block Diagram 6V Internal Regulator I 1 Fault C T CINT Normal VDD 2I 1 CHARGE V BOOST Q1 PUMP Sense+ 15V Sense- ON 50mV OFF 6V ↑ ONE- 10I I Gate Input ↓ SHOT 2 2 Transistor: 106 Pin Description Pin Number Pin Name Pin Function 1 V Supply: +12V to +36V. Decouple with ≥ 10µF capacitor. DD 2 Input TTL Compatible Input: Logic high turns the external MOSFET on. An inter- nal pull-down returns an open pin to logic low. 3 C Retry Timing Capacitor: Controls the off time (t ) of the overcurrent T G(OFF) retry cycle. (Duty cycle adjustment.) • Open = approx. 20% duty cycle. • Capacitor to Ground = approx. 20% to < 1% duty cycle. • Pull-up resistor = approx. 20% to approx. 75% duty cycle. • Ground = maintained shutdown upon overcurrent condition. 4 Gnd Circuit Ground 5 Sense + Current Sense Comparator (+) Input: Connect to high side of sense resistor or current sensing MOSFET sense lead. A built-in offset in conjunction with R sets the load overcurrent trip point. SENSE 6 Sense – Current Sense Comparator (–) Input: Connect to the low side of the sense resistor (usually the high side of the load). 7 Gate Gate Drive: Drives the gate of an external power MOSFET. Also limits V GS to 15V max. to prevent Gate-to-Source damage. Will sink and source cur- rent. 8 V Charge Pump Boost Capacitor: A bootstrap capacitor from V to the BOOST BOOST FET source pin supplies charge to quickly enhance the Gate output during turn-on. MIC5021 2 July 2005

MIC5021 Micrel, Inc. Absolute Maximum Ratings Operating Ratings Supply Voltage (V ) ...................................................+40V Supply Voltage (V ) .....................................+12V to +36V DD DD Input Voltage .................................................–0.5V to +15V Temperature Range Sense Differential Voltage ..........................................±6.5V PDIP .....................................................................–40°C to +85°C SOIC ......................................................–40°C to +85°C Sense + or Sense – to Gnd ...........................–0.5V to +36V Timer Voltage (C ) ......................................................+5.5V T V Capacitor .....................................................0.01µF BOOST Electrical Characteristics T = 25°C, Gnd = 0V, V = 12V, C = Open, Gate C = 1500pF (IRF540 MOSFET) unless otherwise specified A DD T L Symbol Parameter Condition Min Typ Max Units D.C. Supply Current V = 12V, Input = 0V 1.8 4 mA DD V = 36V, Input = 0V 2.5 6 mA DD V = 12V, Input = 5V 1.7 4 mA DD V = 36V, Input = 5V 2.5 6 mA DD Input Threshold 0.8 1.4 2.0 V Input Hysteresis 0.1 V Input Pull-Down Current Input = 5V 10 20 40 µA Current Limit Threshold Note 1 30 50 70 mV Gate On Voltage V = 12V Note 2 16 18 21 V DD V = 36V Note 2 46 50 52 V DD t Gate On Time, Fixed Sense Differential > 70mV 2 6 10 µs G(ON) t Gate Off Time, Adjustable Sense Differential > 70mV, C = 0pF 10 20 50 µs G(OFF) T t Gate Turn-On Delay Note 3 500 1000 ns DLH t Gate Rise Time Note 4 400 500 ns R t Gate Turn-Off Delay Note 5 800 1500 ns DLH t Gate Fall Time Note 6 400 500 ns F f Maximum Operating Frequency Note 7 100 150 kHz max Note 1 When using sense MOSFETs, it is recommended that R < 50Ω. Higher values may affect the sense MOSFET’s current transfer ratio. SENSE Note 2 DC measurement. Note 3 Input switched from 0.8V (TTL low) to 2.0V (TTL high), time for Gate transition from 0V to 2V. Note 4 Input switched from 0.8V (TTL low) to 2.0V (TTL high), time for Gate transition from 2V to 17V. Note 5 Input switched from 2.0V (TTL high) to 0.8V (TTL low), time for Gate transition from 20V (Gate on voltage) to 17V. Note 6 Input switched from 2.0V (TTL high) to 0.8V (TTL low), time for Gate transition from 17V to 2V. Note 7 Frequency where gate on voltage reduces to 17V with 50% input duty cycle. July 2005 3 MIC5021

MIC5021 Micrel, Inc. Typical Characteristics Supply Current vs. Gate Voltage Change Gate Turn-On Dalay vs. Supply Voltage vs. Supply Voltage Supply Voltage 2.5 25 900 VGATE=VGATE–VSUPPLY VGATE=VSUPPLY+4V 2.0 VIN=0V 20 850 CL=1500pF(IRCZ34) C =0.01µF (mA)UPPLY11..05 VIN=5V V (V)GATE1105 (ns)ON 4V785000 BOOST S t I INCLUDES PROPAGATION DELAY 0.5 5 700 0.0 0 650 5 10 15 20 25 30 35 40 5 10 15 20 25 30 35 40 5 10 15 20 25 30 35 40 V (V) V (V) V (V) SUPPLY SUPPLY SUPPLY Gate Turn-On Delay vs. GateTurn-On Delayvs. Gate Turn-Off Delay vs. Supply Voltage GateCapacitance Supply Voltage 1000 2.5 2000 VGATE=VSUPPLY+10V VGATE=VSUPPLY+4V VGATE=VSUPPLY+4V 950 CL=1500pF(IRCZ34) 2.0 VSUPPLY=12V 1750 RL=400 C =0.01µF BOOST (ns)ON 10V895000 t(µs)ON11..05 (ns)OFF 4V11255000 CGATE=1500pF t t (IRCZ34) 800 0.5 1000 INCLUDES PROPAGATION DELAY INCLUDES PROPAGATION DELAY INCLUDES PROPAGATION DELAY 750 0.0 750 5 10 15 20 25 30 35 40 1x1001x1011x1021x1031x1041x105 5 10 15 20 25 30 35 40 VSUPPLY (V) CGATE (pF) VSUPPLY (V) Overcurrent Retry Duty Input Current vs. Sense Threshold vs. Cycle vs. Timing Capacitance Input Voltage Temperature 25 100 80 t =5µs V =12V E (%)20 VSUOPNPLY=12V 80 SUPPLY 70 DUTY CYCL1105 NOTE: I(µA)IN4600 LTAGE (mV)5600 RY tON,tOFFTIME VO40 RET 5 IONDFEVPSEUPNPDLYENT 20 30 0 0 20 0.1 1 10 100 1000 10000 0 5 10 15 20 25 -60 -30 0 30 60 90 120 150 C (pF) V (V) TEMPERATURE (°C) T IN TTL (H) Input 0V 15V (max.) Gate Source Sense +,– 50mV Differential 0V Timing Diagram 1. Normal Operation 6µs 20µs 6µs TTL (H) TTL (H) Input Input 0V 0V 15V (max.) 15V (max.) Gate Gate Source Source Sense +,– Sense +,– 50mV 50mV Differential Differential 0V 0V Timing Diagram 2. Fault Condition, C = Open Timing Diagram 3. Fault Condition, C = Grounded T T MIC5021 4 July 2005

MIC5021 Micrel, Inc. Functional Description An internal zener diode protects the external MOSFET by limiting the gate to source voltage. Refer to the MIC5021 block diagram. Sense Inputs Input The MIC5021’s 50mV (nominal) trip voltage is created by A signal greater than 1.4V (nominal) applied to the MIC5021 internal current sources that force approximately 5µA out of INPUT causes gate enhancement on an external MOSFET SENSE + and approximately 15µA (at trip) out of SENSE –. turning the MOSFET on. When SENSE – is 50mV or more below SENSE +, SENSE – An internal pull-down resistor insures that an open INPUT steals base current from an internal drive transistor shutting remains low, keeping the external MOSFET turned off. off the external MOSFET. Gate Output Overcurrent Limiting Rapid rise and fall times on the GATE output are possible Current source I charges C upon power up. An optional 1 INT because each input state change triggers a one-shot which external capacitor connected to C is kept discharged through T activates a high-value current sink (10I ) for a short time. 2 a MOSFET Q1. This draws a high current though a current mirror circuit A fault condition (> 50mV from SENSE + to SENSE –) causes causing the output transistors to quickly charge or discharge the overcurrent comparator to enable current sink 2I which the external MOSFET’s gate. 1 overcomes current source I to discharge C in a short 1 INT A second current sink continuously draws the lower value time. When C is discharged, the INPUT is disabled, which INT of current used to maintain the gate voltage for the selected turns off the gate output, and C and C are ready to be INT T state. charged. An internal charge pump utilizes an external “boost” capacitor When the gate output turns the MOSFET off, the overcurrent connected between V and the source of the external BOOST signal is removed from the sense inputs which deactivates MOSFET. (Refer to typical application.) The boost capacitor current sink 2I . This allows C and the optional capacitor 1 INT stores charge when the MOSFET is off. As the MOSFET connected to C to recharge. A Schmitt trigger delays the T turns on, its source to ground voltage increases and is added retry while the capacitor(s) recharge. Retry delay is increased to the voltage across the capacitor, raising the V pin BOOST by connecting a capacitor to C (optional). T voltage. The boost capacitor charge is directed through The retry cycle will continue until the fault is removed or the the GATE pin to quickly charge the MOSFET’s gate to 16V input is changed to TTL low. maximum above V . The internal charge pump maintains DD the gate voltage. If CT is connected to ground, the circuit will not retry upon a Applications Information Supply Voltage The MIC5021 MOSFET driver is intended for high-side The MIC5021’s supply input (VDD) is rated up to 36V. The switching applications where overcurrent limiting and high supply voltage must be equal to or greater than the voltage speed are required. The MIC5021 can control MOSFETs applied to the drain of the external N-channel MOSFET. that switch voltages up to 36V. A 16V minimum supply is recommended to produce continu- High-Side Switch Circuit Advantages ous on-state, gate drive voltage for standard MOSFETs (10V nominal gate enhancement). High-side switching allows more of the load related com- ponents and wiring to remain near ground potential when When the driver is powered from a 12V to 16V supply, a compared to low-side switching. This reduces the chances logic-level MOSFET is recommended (5V nominal gate of short-to-ground accidents or failures. enhancement). Speed Advantage PWM operation may produce satisfactory gate enhancement at lower supply voltages. This occurs when fast switching The MIC5021 is about two orders of magnitude faster than repetition makes the boost capacitor a more significant volt- the low cost MIC5014 making it suitable for high-frequency age supply than the internal charge pump. high-efficiency circuit operation in PWM (pulse width modu- lation) designs used for motor control, SMPS (switch mode power supply) and heating element control. Switched loads (on/off) benefit from the MIC5021’s fast switching times by allowing use of MOSFETs with smaller safe operating areas. (Larger MOSFETs are often required when using slower drivers.) July 2005 5 MIC5021

MIC5021 Micrel, Inc. Logic-Level MOSFET Precautions A 0.01µF boost capacitor is recommended for best perfor- Logic-level MOSFETs have lower maximum gate-to-source mance in the 12V to 20V range. Refer to figure 1. Larger voltage ratings (typically ±10V) than standard MOSFETs capacitors may damage the MIC5021. +12V to +36V (typically ±20V). When an external MOSFET is turned on, the doubling effect of the boost capacitor can cause the gate-to-source voltage to momentarily exceed 10V. Internal MIC5021 10µF 1 8 zener diodes clamp this voltage to 16V maximum which VDD VBOOST is too high for logic-level MOSFETs. To protect logic-level TTL Input 2 Input Gate 7 MOSFETs, connect a zener diode (5V≤V <10V) from 3 6 gate to source. Zener CT Sense- 2n.F7 4 5 Gnd Sense+ Overcurrent Limiting A 50mV comparator is provided for current sensing. The low level trip point minimizes I2R losses when a power resistor is used for current sensing. Load The adjustable retry feature can be used to handle loads with high initial currents, such as lamps or heating elements, and can be adjusted from the C connection. T Figure 2. 12V to 36V Configuration C to ground maintains gate drive shutdown following an T If the full 12V to 36V voltage range is required, the boost overcurrent condition. capacitor value must be reduced to 2.7nF. Refer to Figure C open, or a capacitor to ground, causes automatic retry. T 2. The recommended configuration for the 20V to 36V range The default duty cycle (C open) is approximately 20%. Refer T is to place the capacitor is placed between V and V to the electrical characteristics when selecting a capacitor for DD BOOST as shown in Figure 3. reduced duty cycle. +12V to +36V C through a pull-up resistor to V increases the duty cycle. T DD Increasing the duty cycle increases the power dissipation MIC5021 0.01 in the load and MOSFET under a “fault” condition. Circuits 10µF 1 8 µF VDD VBOOST may become unstable at a duty cycle of about 75% or higher, 2 7 TTL Input Input Gate depending on conditions. Caution: The MIC5021 may be 3 6 damaged if the voltage applied to C exceeds the absolute CT Sense- T 4 5 maximum voltage rating. Gnd Sense+ Boost Capacitor Selection The boost capacitor value will vary depending on the supply voltage range. Load +12V to +20V MIC5021 10µF 1 8 Figure 3. Preferred 20V to 36V Configuration VDD VBOOST 2 7 Do not use both boost capacitor between V and the TTL Input Input Gate BOOST 3 CT Sense- 6 0µ.F01 MOSFET source and VBOOST and VDD at the same time. 4 5 Current Sense Resistors Gnd Sense+ Lead length can be significant when using low value (< 1Ω) resistors for current sensing. Errors caused by lead length can be avoided by using four-teminal current sensing re- sistors. Four-terminal resistors are available from several Load manufacturers. Figure 1. 12V to 20V Configuration MIC5021 6 July 2005

MIC5021 Micrel, Inc. Circuits Without Current Sensing The diode should have a peak forward current rating greater V+ than the load current. This is because the current through the diode is the same as the load current at the instant the MOSFET is turned off. MIC5021 10µF 1 8 +20V to +36V VDD VBOOST 2 7 (+24V) TTL Input Input Gate N-Channel 34 CGnTd SSeennssee-+ 65 0µ.F01 Power MOSFET TTL Inpu1t0µF 12 VInpDMuDtIC5V0BG2OaO1tSeT 87 0µ.F01 N-Channel Power MOSFET Load 3 6 (IRF540) CT Sense- 4 5 Gnd Sense+ Figure 4a. Connecting Sense to Source RSENSE V+ (< 0.08Ω) Solenoid Schottky MIC5021 (24V, 47Ω) Diode 10µF 1 8 (1N5822) VDD VBOOST 2 7 TTL Input Input Gate N-Channel Power MOSFET 3 6 CT Sense- 0.01 Figure 5. Solenoid Driver 4 Gnd Sense+ 5 µF with Current Sensing Load Sense Pin Considerations The sense pins of the MIC5021 are sensitive to negative volt- Figure 4b. Connecting Sense to Supply ages. Forcing the sense pins much below –0.5V effectively reverses the supply voltage on portions of the driver resulting Current sensing may be omitted by connecting the SENSE + in unpredictable operation or damage. and SENSE – pins to the source of the MOSFET or to the sup- MIC5021 ply. Connecting the SENSE pins to the supply is preferred for 1 8 inductive loads. Do not connect the SENSE pins to ground. VDD 2 7 Input Gate Inductive Load Precautions MOSFET 3 6 Turnoff Circuits controlling inductive loads, such as solenoids (Figure CT ~VDD 4 5 0V 5) and motors, require precautions when controlled by the Negative MIC5021. Wire wound resistors, which are sometimes used Spike to simulate other loads, can also show significant inductive Forward drop across diodes properties. allows leads to go negative. Inductive Load Current flows from ground (0V) An inductive load releases stored energy when its current through the diodes to the load flow is interrupted (when the MOSFET is switched off). The during negative transcients. voltage across the inductor reverses and the inductor at- Figure 6. Inductive Load Turnoff tempts to force current flow. Since the circuit appears open Figure 6 shows current flowing out of the sense leads of an (the MOSFET appears as a very high resistance) a very large MIC5021 during a negative transient (inductive kick). Internal negative voltage occurs across the inductor. Schottky diodes attempt to limit the negative transient by Limiting Inductive Spikes maintaining a low forward drop. The voltage across the inductor can be limited by connect- Although the internal Schottky diodes can protect the driver ing a Schottky diode across the load. The diode is forward in low-current resistive applications, they are inadequate for biased only when the load is switched off. The Schottky diode inductive loads or the lead inductance in high-current resis- clamps negative transients to a few volts. This protects the tive loads. Because of their small size, the diodes’ forward MOSFET from drain-to-source breakdown and prevents the voltage drop quickly exceeds 0.5V as current increases. transient from damaging the charge pump by way of the boost capacitor. Also see Sense Pin Considerations below. July 2005 7 MIC5021

MIC5021 Micrel, Inc. External Protection High-Side Sensing Resistors placed in series with each SENSE connection limit Sensing the current on the high side of the MOSFET isolates the current drawn from the internal Schottky diodes during a the SENSE pins from the inductive spike. negative transient. This minimizes the forward drop across +12V to +20V (+12V) the diodes. MIC5021 12 VDD VBOOST 87 10µF 1 VDDMIC5V0B2O1OST 8 R(<S E0N.0S1EΩ) Input Gate NP-oCwhearn nMeOlSFET TTL Input 2 Input Gate 7 N-Channel 3 6 Power MOSFET 4 CT Sense- 5 R1 3 CT Sense- 6 (IRFZ44) Gnd Sense+ 4 5 Gnd Sense+ 5µA VR1 RS 5 0 (matV t rnipo)minal 0µ.0F1 R2 Wirewound V =V R1 R2 Resistor to avoid skewing 15µA (3Ω) the 50mV trip point. VR2 Load (5mV suggested) R1≅ 3× R2 Figure 9. High Side Sensing Figure 7. Resistor Voltage Drop Lamp Driver Application During normal operation, sensing current from the sense pins Incandescent lamps have a high inrush current (low resis- is unequal (5µA and 15µA). The internal Schottky diodes are tance) when turned on. The MIC5021 can perform a “soft reverse biased and have no effect. To avoid skewing the trip start” by pulsing the MOSFET (overcurrent condition) until voltage, the current limiting resistors must drop equal volt- the filament is warm and its current decreases (resistance ages at the trip point currents. See Figure 7. To minimize increases). The sense resistor value is selected so the voltage resistor tolerance error, use a voltage drop lower than the drop across the sense resistor decreases below the sense trip voltage of 50mV. 5mV is suggested. threshold (50mV) as the filament becomes warm. The FET External Schottky diodes are also recommended. See D2 is no longer pulsed and the lamp turns completely on. and D3 in Figure 8. The external diodes clamp negative V+ transients better than the internal diodes because their larger (+12V) size minimizes the forward voltage drop at higher currents. +12V to +36V MIC5021 10µF 1 8 VDD VBOOST 2 7 MIC5021 TTL Input Input Gate NP-oCwhearn nMeOlSFET 10µF 1 8 3 6 (IRF540) VDD VBOOST CT Sense- 0.01 2 7 4 5 µF TTL Input Input Gate N-Channel Gnd Sense+ Power MOSFET 3 6 2.7 R CT Sense- nF (0S.E0N4S1EΩ) 4 5 R1 Gnd Sense+ D2 1.0k R "( )" values apply to demo circuit. ILnacmanpd (e#s1c1e5n7t) 11DQ03 SENSE See text. R2 D3 330Ω 11DQ03 Figure 10. Lamp Driver with Inductive Current Sensing D1 Load A lamp may not fully turn on if the filament does not heat up adequately. Changing the duty cycle, sense resistor, or both to match the filament characteristics can correct the problem. Figure 8. Protection from Inductive Kick Soft start can be demonstrated using a #1157 dual filament automotive lamp. The value of R shown in Figure 10 allows S for soft start of the higher-resistance filament (measures ap- prox. 2.1Ω cold or 21Ω hot). MIC5021 8 July 2005

MIC5021 Micrel, Inc. Remote Overcurrent Limiting Reset +12V to +36V In circuit breaker applications where the MIC5021 maintains an off condition after an overcurrent condition is sensed, the MIC5021AJB CT pin can be used to reset the MIC5021. 10µF 1 VDD VBOOST 8 +12V to +20V 2 7 TTL Input Input Gate 3 6 CT Sense- 2.7 MIC5021 4 5 nF 2.2M 10µF 1 VDD VBOOST 8 Gnd Sense+ TTL Input 2 Input Gate 7 N-Channel RSENSE Power 10k to 3 6 MOSFET add resistor for 100k 2N3904 CT Sense- 0.01 –40°C to –55°C Q1 4 5 µF operation 74HC04 Gnd Sense+ Load (example) R SENSE Retry (H) Maintained (L) Figure 12a. Gate-to-Source Pull Down Load The gate-to-source configuration (refer to Figure 12a) is appropriate for resistive and inductive loads. This also causes the smallest decrease in gate output voltage. Figure 11. Remote Control Circuit +12V to +36V Switching Q1 on pulls C low which keeps the MIC5021 GATE T output off when an overcurrent is sensed. Switching Q1 off MIC5021AJB causes CT to appear open. The MIC5021 retries in about 10µF 1 VDD VBOOST 8 20µs and continues to retry until the overcurrent condition 2 7 TTL Input Input Gate is removed. 3 6 CT Sense- 2.7 For demonstration purposes, a 680Ω load resistor and 3Ω 4 5 nF sense resistor will produce an overcurrent condition when the Gnd Sense+ R load’s supply (V+) is approximately 12V or greater. SENSE Low-Temperature Operation add resistor for As the temperature of the MIC5021AJB (extended temperature –40°C to –55°C 2.2M Load range version—no longer available) approaches –55°C, the operation driver’s off-state, gate-output offset from ground increases. If the operating environment of the MIC5021AJB includes low temperatures (–40°C to –55°C), add an external 2.2MΩ Figure 12b. Gate-to-Ground Pull Down resistor as shown in Figures 12a or 12b. This assures that The gate-to-ground configuration (refer to Figure 12b) is ap- the driver’s gate-to-source voltage is far below the external propriate for resistive, inductive, or capacitive loads. This MOSFET’s gate threshold voltage, forcing the MOSFET configuration will decrease the gate output voltage slightly fully off. more than the circuit shown in Figure 12a. July 2005 9 MIC5021

MIC5021 Micrel, Inc. Package Information PIN 1 DIMENSIONS: INCH (MM) 0.380 (9.65) 0.255 (6.48) 0.370 (9.40) 0.135 (3.43) 0.245 (6.22) 0.125 (3.18) 0.300 (7.62) 0.013 (0.330) 0.010 (0.254) 0.018 (0.57) 0.130 (3.30) 0.380 (9.65) 0.320 (8.13) 0.100 (2.54) 0.0375 (0.952) 8-Pin Plastic DIP (N) 0.026 (0.65) MAX) PIN 1 0.157 (3.99) DIMENSIONS: 0.150 (3.81) INCHES (MM) 0.020 (0.51) 0.013 (0.33) 0.050 (1.27) TYP 0.0098 (0.249) 45° 0.010 (0.25) 0.0040 (0.102) 0.007 (0.18) 0.197 (5.0) 0°–8° 0.050 (1.27) 0.064 (1.63) 0.189 (4.8) SEATING 0.016 (0.40) 0.045 (1.14) PLANE 0.244 (6.20) 0.228 (5.79) 8-Pin SOIC (M) 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 This information furnished by Micrel in this data sheet is believed to be accurate and reliable. However no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. 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. © 2003 Micrel, Inc. MIC5021 10 July 2005

Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: M icrochip: MIC5021YN MIC5021YM MIC5021YM-TR