MIC5060_10 MICREL | Alldatasheet

Document overview

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Technical content

Features

  • 2.75V to 30V operation
  • 100µA maximum supply current (5V supply)
  • 15µA typical off-state current
  • Internal charge pump
  • TTL-compatible input
  • Withstands 60V transient (load dump)
  • Reverse battery protected to –20V
  • Inductive spike protected to –20V
  • Overvoltage shutdown at 35V
  • Internal 15V gate protection
  • Minimum external parts
  • Operates in high-side or low-side configurations
  • 1µA control input pull-off
  • Available in 8-pin 3mm x 3mm MLF ® package

Applications

  • Notebook Battery safety switches
  • UMPC and Web Tablet Battery protection
  • Battery-powered computer power management
  • General MOSFET switch applications
  • Power bus switching Typical Application 3V “Sleep-Mode” Switch with a Logic-Level MOSFET

Micrel, Inc. MIC5060 February 2010 2 M9999-021610-C Ordering Information(1, 2) Part Number Marking Code Temperature Range Configuration Package MIC5060YML MIC5060 -40°C to +85°C Non-Inverting 8-pin 3mm x 3mm MLF ® Note: 1. Pin 1 identifier symbol is “•”. 2. MLF is a Green RoHS-compliant package. Lead finish is NiPdAu. Mold compound is Halogen free. Pin Configuration 8-Pin (3mm x 3mm) MLF® (ML) Top View Pin Description Pin Number Pin Name Pin Function 1 V+ Supply. Must be decoupled to isolate from large transients caused by the power MOSFET drain. 10µF is recommended close to pins 1 and 4. 2 Input Turns on power MOSFET when taken above (or below) threshold (1.0V typical). Pin 2 requires ~ 1µA to switch. 3 Source Connects to source lead of power MOSFET and is the return for the gate clamp zener. Pin 3 can safely swing to –20V when turning off inductive loads. 4 Ground Ground. 5 Gate Drives and clamps the gate of the power MOSFET. 6, 7, 8 NC Not internally connected.

Micrel, Inc. MIC5060 February 2010 3 M9999-021610-C Absolute Maximum Ratings(1) Operating Ratings(2) Junction Thermal Resistance Electrical Characteristics(3) TJ = TA = -40°C to +85°C unless otherwise specified. Parameter Condition Min. Typ. Max. Units VIN De-Asserted, Note 4 10 25 µA V+ = 30V VIN Asserted, Note 4 5.0 10 mA VIN De-Asserted, Note 4 10 25 µA V+ = 5V VIN Asserted, Note 4 60 100 µA VIN De-Asserted, Note 4 10 25 µA Supply Current V+ = 3V VIN Asserted, Note 4 25 35 µA Digital Low Level 0.8 V Logic Input Voltage Threshold VIN 2.75V ≤ V+ ≤ 30V TA = 25°C Digital High Level 2.0 VIN Low -2.0 0 µA Logic Input Current MIC5060 2.75V ≤ V+ ≤ 30V VIN High 1.0 2.0 µA Gate Enhancement VGATE – VSUPPLY 3.0V ≤ V+ ≤ 30V V IN Asserted 3.0 17 V Zener Clamp VGATE – VSOURCE 8.0V ≤ V+ ≤ 30V V IN Asserted 13 15 17 V V+ = 4.5V CL = 1000pF VIN switched on, measure time for VGATE to reach V+ + 4V 2.5 8.0 ms Gate Turn-on Time, tON Note 5 V+ = 12V CL = 1000pF As above, measure time for VGATE to reach V+ + 4V 90 140 µs V+ = 4.5V CL = 1000pF VIN switched off, measure time for VGATE to reach 1V 6.0 30 µs Gate Turn-off Time, tOFF Note 5 V+ = 12V CL = 1000pF As above, measure time for VGATE to reach 1V 6.0 30 µs Overvoltage Shutdown Threshold 35 37 41 V Notes: 1. Exceeding the absolute maximum rating may damage the device. 2. The device is not guaranteed to function outside its operating rating. 3. Minimum and maximum Electrical C haracteristics are 100% tested at T A = 25°C and TA = 85°C, and 100% guaranteed over the entire operating temperature range. Typicals are characterized at 25°C and represent the most likely parametric norm. 4. “Asserted” refers to a logic high on the MIC5060. 5. Test conditions reflect worst-case high-side driver performance. Low-side and bootstrapped topologies are significantly faster—see Applications Information.

Micrel, Inc. MIC5060 February 2010 4 M9999-021610-C Typical Characteristics

Micrel, Inc. MIC5060 February 2010 5 M9999-021610-C

Micrel, Inc. MIC5060 February 2010 6 M9999-021610-C Block Diagram

Micrel, Inc. MIC5060 February 2010 7 M9999-021610-C

Application Information

The internal functions of the MIC5060 is controlled via a logic block (refer to block diagram) connected to the control input (pin 2). When the input is off (low), all functions are turned off, and the gate of the external power MOSFET is held low via two N-Channel switches. This results in a very low standby current, 15µA typical, which is necessary to power an internal bandgap. When the input is driven to the “ON” state, the N-Channel switches are turned off, the charge pump is turned on, and the P-Channel switch between the charge pump and the gate turns on, allowing the gate of the power FET to be charged. The op amp and internal zener form an active regulator which shuts off the charge pump when the gate voltage is high enough. The charge pump incorporates a 100kHz oscillator and on- chip pump capacitors capable of charging a 1000pF load in 90µs typical. In addition to providing active regulation, the internal 15V zener is included to prevent exceeding the VGS rating of the power MOSFET at high supply voltages. The MIC5060 device has been improved for greater ruggedness and durability. All pins can withstand being pulled 20V below ground without sustaining damage, and the supply pin can withstand an overvoltage transient of 60V for 1s. An overvoltage shutdown has also been included, which turns off the device when the supply exceeds 35V. Construction Hints High current pulse circuits demand equipment and assembly techniques that ar e more stringent than normal, low current lab practices. The following are the sources of pitfalls most often encountered during prototyping: Supplies: Many bench power supplies have poor transient response. Circuits that are being pulse tested, or those that operate by pulse-width modulation will produce strange results when used with a supply that has poor ripple rejection, or a peaked transient response. Always monitor the power supply voltage that appears at the drain of a high side driver (or the supply side of the load for a low side driver) with an oscilloscope. It is not uncommon to find bench power supplies in t he 1kW class that overshoot or undershoot by as much as 50% when pulse loaded. Not only will the load current and voltage measurements be affected, but also it is possible to overstress various components, especially electrolytic capacitors, with possibly catastrophic results. A 10µF supply bypass capacitor at the chip is recommended. Residual resistances: Resistances in circuit connections may also cause confusing results. For example, a circuit may employ a 50mΩ power MOSFET for low voltage drop, but unless careful construction techniques are used, one could easily add 50m Ω to 100m Ω resistance. Do not use a socket for the MOSFET. If the MOSFET is a TO-220 type package, make high current conne ctions to the drain tab. Wiring losses have a profound effect on high-current circuits. A floating milliohmet er can identify connections that are contributing excess drop under load. Low Voltage Testing As the MIC5060 has relatively high output impedances, a normal oscilloscope probe will load the device. This is especially pronounced at lo w voltage operation. It is recommended that a FET probe or unity gain buffer be used for all testing. Circuit Topologies The MIC5060 is well suited for use with standard power MOSFETs in both low and high side driver configurations. In addition, the lowered supply voltage requirements of these devices make them ideal for use with logic level FETs in high side applications with a supply voltage of 3V to 4V. (If higher supply voltages [>4V] are used with logic level FETs, an external zener clamp must be supplied to ensure that the maximum V GS rating of the logic FET [10V] is not exceeded.) In addition, a standard IGBT can be driven using these devices. Choice of one topology over another is usually based on speed vs. safety. The fastest topology is the low side driver, however, it is not us ually considered as safe as high side driving as it is easier to accidentally short a load to ground than to V CC. The slowest, but safest topology is the high side driver; with speed being inversely proportional to supply voltage. It is the preferred topology for most military and automotive applications. Speed can be improved considerably by bootstrapping from the supply. All topologies implemented using these devices are well suited to driving inductive load s, as either the gate or the source pin can be pulled 20V below ground with no effect. External clamp diodes are unnecessary, except for the case in which a transient may exceed the overvoltage trip point.

Figure 4. High Side Driver with Overcurrent Shutdown

Micrel, Inc. MIC5060 February 2010 12 M9999-021610-C

Package Information

8-Pin (3mm x 3mm) MLF® (ML) MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB H U http://www.micrel.comU H The 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. © 2009 Micrel, Incorporated.