MIC94044/5 28mΩ RDSON 3A High Side Load Switch in 1.2mm x 1.2mm MLF® Package General Description Features The MIC94044 and MIC94045 are high-side load switches designed to operate from 1.7V to 5.5V input voltage. The load switch pass element is an internal 28mΩ RDSON P-channel MOSFET which enables the device to support up to 3A of continuous current. Additionally, the load switch supports 1.5V logic level control and shutdown features in a tiny 1.2mm x 1.2mm 4 pin MLF® package. The MIC94044/5 provides a slew rate controlled soft-start turn-on of 1ms (typical) to prevent an in-rush current event from pulling down the input supply voltage. The MIC94045 features an active load discharge circuit which switches in a 200Ω load when the switch is disabled to automatically discharge a capacitive load. Internal level shift circuitry allows low voltage logic signals to switch higher supply voltages. The enable voltage can be as high as 5.5V and is not limited by the input voltage. The MIC94044/5 operating voltage range makes them ideal for Lithium ion and NiMH/NiCad/Alkaline battery powered systems, as well as non-battery powered applications. The devices provide low quiescent current and low shutdown current to maximize battery life. Data sheets and support documentation can be found on Micrel’s web site at: www.micrel.com. • • • • • • • • • • • 28mΩ RDSON 3A continuous operating current 1.2mm x 1.2mm space saving 4-pin MLF® package 1.7V to 5.5V input voltage range Internal level shift for CMOS/TTL control logic Ultra low quiescent current Micro-power shutdown current Soft-Start: 1ms Load discharge circuit: MIC94045 Ultra fast turn off time Junction operating temperature from -40ºC to +125ºC Applications • • • • • • • • • Solid State Drives (SSD) Cellular phones Portable Navigation Devices (PND) Personal Media Players (PMP) Ultra Mobile PCs Portable instrumentation Other Portable applications PDAs Industrial and DataComm equipment ____________________________________________________________________________________________________________ Typical Application MIC94044 (1ms soft-start) MIC94045 (1ms soft-start with auto-discharge) MLF and MicroLeadFrame are registered trademarks of Amkor Technology, 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 2011 M9999-032311-A Micrel, Inc. MIC94044/5 Ordering Information Part Number Marking Soft-Start MIC94044YFL P5 1ms MIC94045YFL P6 1ms Load Discharge Package 4-Pin 1.2mm x 1.2mm MLF® ― 4-Pin 1.2mm x 1.2mm MLF® Notes: ® 1. MLF Pin 1 Identifier symbol is “z”. 2. Over bar symbol (¯¯) may not be to scale. ® 3. MLF is a GREEN RoHS-compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free. Pin Configuration 4-Pin 1.2mm x 1.2mm MLF® (Top View) Pin Description Pin Number Pin Name Description 1 VOUT Drain of P-channel MOSFET. 2 GND Ground should be connected to electrical ground. 3 VIN Source of P-channel MOSFET. 4 EN Enable (Input): Active-high CMOS/TTL control input for switch. Do not leave floating. March 2011 2 M9999-032311-A Micrel, Inc. MIC94044/5 Absolute Maximum Ratings (1) Operating Ratings (2) Input Voltage (VIN) ........................................................ +6V Enable Voltage (VEN) ................................................... +6V Continuous Drain Current (ID) (3) TA = 25°C .............................................................. ±3A TA = 85°C .............................................................. ±2A Pulsed Drain Current (IDP)(4) ...................................... ±6.0A Continuous Diode Current (IS)(5) .............................. –50mA Storage Temperature (Ts) ....................... –55°C to +150°C ESD Rating – HBM(6)...................................................... 3kV Input Voltage (VIN)....................................... +1.7 to +5.5V Junction Temperature (TJ) .....................–40°C to +125°C Package Thermal Resistance 1.2mm x 1.2mm MLF® -4L(θJC) .........................90°C/W Electrical Characteristics (7) TA = 25°C, bold values indicate –40°C< TJ < +85°C, unless noted. Symbol Parameter Condition Min VEN_TH Enable Threshold Voltage VIN = 1.7V to 4.5V, ID = –250µA 0.4 IQ Quiescent Current VIN = VEN = 5.5V, ID = OPEN IEN Enable Input Current ISHUT-Q Typ Max Units 1.2 V 2.25 10 µA VIN = VEN = 5.5V, ID = OPEN 0.1 1 µA Quiescent Current (shutdown) VIN = +5.5V, VEN = 0V, ID = OPEN Measured on VIN 0.1 1 µA ISHUT-SWITCH OFF State Leakage Current VIN = +5.5V, VEN = 0V, ID = SHORT (7) Measured on VOUT, 0.1 1 µA RDS(ON) P-Channel Drain to Source ON Resistance VIN = +5.0V, ID = –100mA, VEN = 1.5V 28 55 mΩ VIN = +4.5V, ID = –100mA, VEN = 1.5V 30 60 mΩ VIN = +3.6V, ID = –100mA, VEN = 1.5V 33 65 mΩ VIN = +2.5V, ID = –100mA, VEN = 1.5V 45 90 mΩ mΩ Measured on VIN VIN = +1.8V, ID = –100mA, VEN = 1.5V 72 145 VIN = +1.7V, ID = –100mA, VEN = 1.5V 82 160 mΩ Turn-Off Resistance VIN = +3.6V, ITEST = 1mA, VEN = 0V MIC94045 200 400 Ω tON_DLY Turn-On Delay Time VIN = +3.6V, ID = –100mA, VEN = 1.5V 0.2 0.85 1.5 ms tON_RISE Turn-On Rise Time VIN = +3.6V, ID = –100mA, VEN = 1.5V 0.4 1 1.5 ms tOFF_DLY Turn-Off Delay Time VIN = +3.6V, ID = –100mA, VEN = 0V 100 200 ns tOFF_FALL Turn-Off Fall Time VIN = +3.6V, ID = –100mA, VEN = 0V 20 100 ns RSHUTDOWN Dynamic (No Output Capacitor) Notes: 1. Exceeding the absolute maximum rating may damage the device. 2. The device is not guaranteed to function outside its operating rating. 3. With thermal contact to PCB. See power dissipation considerations section. 4. Pulse width <300µs with < 2% duty cycle. 5. Continuous body diode current conduction (reverse conduction, i.e. VOUT to VIN) is not recommended. 6. Devices are ESD sensitive. Handling precautions recommended. HBM (Human body model), 1.5kΩ in series with 100pF. 7. Measured on the MIC94044YFL. March 2011 3 M9999-032311-A Micrel, Inc. MIC94044/5 Typical Characteristics RDSON Variance vs. Temperature Voltage Drop vs. Output Current 400 1.0 300 250 VIN = 3.6V 200 VIN = 4.2V VIN = 2.5V 150 20 40 60 1000 Rise Time vs. Input Voltage 1.5 Enable Current vs. Temperature TA = 25˚C 0.7 0.6 TA = 125˚C VEN = 1.5V 8 7 6 5 VIN = 5.5V 4 VIN = 3.6V 3 2 VIN =1.5V 1 QUIESCENT CURRENT (µA) 0.9 0.5 2.5 3.0 3.5 4.0 4.5 5.0 -40 -20 5.5 Quiescent Current vs. Temperature VIN = 5.5V VIN = 3.6V 2.0 1.5 VIN =1.5V 1.0 0.5 0.0 1.0 COUT = 1µF 160 140 120 100 MIC94045 80 MIC94044 60 40 1.5 1.0 T = 125°C 0.5 2.7 3.2 200 2.5 3.0 3.5 4.0 4.5 5.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE (V) 0.9 0.8 0.7 0.6 5.5 COUT = 1µF IOUT = 100mA 1.5 2.0 2.5 3.0 3.5 4.0 4.5 TOFF Delay Time vs. Input Voltage Output Voltage vs. Input Voltage 100mA Load No Output Capacitor MIC94045 120 100 80 MIC94044 40 0 0 1.0 INPUT VOLTAGE (V) 160 60 5.2 5.7 TON Rise Time vs. Input Voltage INPUT VOLTAGE (V) 180 140 3.7 4.2 4.7 0.4 2.0 20 20 March 2011 2.0 0.5 IOUT = 100mA 5.0 5.5 6 OUTPUT VOLTAGE (V) 100mA Load No Output Capacitor 5.5 T = -45°C 1.2 1.5 1.5 TOFF DELAY TIME (ns) 180 5.0 T = 20°C 2.5 1.7 2.2 0.0 200 4.5 INPUT VOLTAGE (V) 2.0 0 20 40 60 80 100 120 TEMPERATURE (°C) TOFF Fall Time vs. Input Voltage 4.0 1.1 0.5 -40 -20 3.0 60 80 100 120 140 2.5 TON DELAY (ms) 2.5 20 40 TON Delay vs. Input Voltage 3.0 VIN = VEN 3.5 No Load VIN = EN 3.5 TEMPERATURE (°C) INPUT VOLTAGE (V) 3.0 0 TON RISE TIME (ms) 2.0 3.0 0.0 0 0.4 1.5 2.5 Quiescent Current vs. Input Voltage 4.0 9 ENABLE CURRENT (nA) TA = -40˚C 0.8 2.0 INPUT VOLTAGE (V) 10 1.0 RISE TIME (ms) 25 10000 OUTPUT CURRENT (mA) 1.1 QUIESCENT CURRENT (µA) 100mA 50 100 80 100 120 140 500mA 75 VIN = 5.5V TEMPERATURE (˚C) 1.2 1A 100 100 0 0 1.5A 350 0.8 -40 -20 125 RDS ON (mΩ) 1.2 3A 2A VIN = 1.7V 50 TOFF FALL TIME (ns) RDSON vs. VIN 150 450 VOLTAGE DROP (mV) RDSON (NORMALIZED) 1.4 5 4 ILOAD = 3A 3 2 1 0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE (V) 4 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE (V) M9999-032311-A Micrel, Inc. MIC94044/5 Functional Characteristics March 2011 5 M9999-032311-A Micrel, Inc. MIC94044/5 Application Information Power Switch SOA The safe operating area (SOA) curve represents the boundary of maximum safe operating current and maximum safe operating ambient temperature. 3.5 Maximum Switch Current vs. Ambient Temperature (1" Square Copper) OUTPUT CURRENT (A) Figure 3: Simple Thermal Circuit VIN = 5V 3.0 V IN = 4.5V 2.5 Now replacing the variables in the equation for VX, we can find the junction temperature (TJ) from power dissipation, ambient temperature and the known thermal resistance of the PCB (RθCA) and the package (RθJC). VIN = 3.6V 2.0 1.5 VIN = 2.5V 1.0 TJ = PDISS x (RθJC + RθCA) + TA 0.5 PDISS is calculated as ISWITCH2 x RSWmax. RθJC is found in the operating ratings section of the datasheet and RθCA (the PCB thermal resistance) values for various PCB copper areas is discussed in the document “Designing with Low Dropout Voltage Regulators” available from the Micrel website (LDO Application Hints). 0.0 -40 -20 0 20 40 60 80 100 120 140 AMBIENT TEMPERATURE (°C) Figure 1: SOA Graph The curves above show the SOA for various values of VIN, mounted on a typical 1 layer, 1 square inch copper board. Power Dissipation Considerations As with all power switches, the current rating of the switch is limited mostly by the thermal properties of the package and the PCB it is mounted on. There is a simple ohms law type relationship between thermal resistance, power dissipation and temperature, which are analogous to an electrical circuit: Figure 2: Simple Electrical Circuit From this simple circuit we can calculate VX if we know ISOURCE, VZ and the resistor values, RXY and RYZ using the equation: VX = ISOURCE (R XY + R YZ ) + VZ Thermal circuits can be considered using these same rules and can be drawn similarly by replacing current sources with power dissipation (in Watts), resistance with thermal resistance (in oC/W) and voltage sources with temperature (in oC). March 2011 6 M9999-032311-A Micrel, Inc. MIC94044/5 Summary of variables: Example: A switch is intended to drive a 2A load and is placed on a printed circuit board which has a ground plane area of at least 25mm x 25mm (625mm2). The Voltage source is a Li-ion battery with a lower operating threshold of 3V and the ambient temperature of the assembly can be up to 50oC. ISW = 2A VIN = 3V to 4.2V TA = 50oC RθJC = 90oC/W from Datasheet RθCA = 53oC/W Read from Graph in Figure 4 PDISS = ISW2 x RSWmax The worst case switch resistance (RSWmax) at the lowest VIN of 3V is not available in the datasheet, so the next lower value of VIN is used. RSWmax @ 2.5V = 90mΩ If this were a figure for worst case RSWmax for 25oC, an additional consideration is to allow for the maximum junction temperature of 125oC, the actual worst case resistance in this case can be 30% higher (See RDSON variance vs. temperature graph). However, 90mΩ is the maximum over temperature. Therefore: TJ = 22 x 0.090 x (90+53) + 50 TJ = 101oC This is below the maximum 125oC. Figure 4: Excerpt from the LDO Book March 2011 7 M9999-032311-A Micrel, Inc. MIC94044/5 Package Information 4-Pin 1.2mm x 1.2mm MLF® March 2011 8 M9999-032311-A Micrel, Inc. MIC94044/5 Recommended Land Pattern 4-Pin 1.2mm x 1.2mm MLF® Land Pattern 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. © 2011 Micrel, Incorporated. March 2011 9 M9999-032311-A