53248 MICROPAC | Alldatasheet

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Micropac Industries cannot assume any responsibility for any circuits shown or represent that they are free from patent infringement. Micropac reserves the right to make changes at any time in order to improve design and to supply the best product possible. MICROPAC INDUSTRIES, INC. HYBRID MICROELECTRONICS PRODUCTS DIVISION • 905 E. Walnut St., Garland, TX 75040 • (972) 272-3571 • Fax (972) 494-2281 www.micropac.com E-MAIL: hybridsales@micropac.com 05/16/01 PRELIMINARY DATA SHEET 53248 28 VDC SOLID STATE POWER CONTROLLER Mii HYBRID MICROELECTRONICS PRODUCTS DIVISION Features:

  • Isolated Controls
  • Isolated Status Outputs
  • Fault Protection Thermal Shutdown Undervoltage & Overvoltage Shutdown Current Limitation Short Circuit Protection Applications:
  • Power Distribution In Land/Air/Launch Vehicles
  • Motor Switch
  • Displays/Lamps/Controls
  • Industrial Automation
  • Switching Heaters
  • Test Equipment
  • Machine Control Equipment
  • Medical Lab Equipment

DESCRIPTION

The 53248 is a 28 VDC Solid State High Side Power Controlle r (SSPC) that is designed to replace electromagnetic circuit breakers rated at 10 amperes. It is a high side switch utilizing N-channel vertical power FET technology with integral charge pump. The SSPC provides a status out put that signals a variety of conditions including over temperature shutdown, overvoltage or undervoltage, over-current or short circuit. It will trip off for any of the above conditions and automatically (based on an internal thermal time constant) cycle On/Off until the fault or the control signal is removed. Using vertical MOSFET technology, the SSPC offers extremely low “ON” resistance. This results in very low power dissipation, which allows operation over the temperature range of –40°C to +85°C with minimal heat sinking. ABSOLUTE MAXIMUM RATINGS (@ TC = 25°C unless otherwise specified)

Micropac Industries cannot assume any responsibility for any circuits shown or represent that they are free from patent infringement. Micropac reserves the right to make changes at any time in order to improve design and to supply the best product possible. MICROPAC INDUSTRIES, INC. HYBRID MICROELECTRONICS PRODUCTS DIVISION • 905 E. Walnut St., Garland, TX 75040 • (972) 272-3571 • Fax (972) 494-2281 www.micropac.com E-MAIL: hybridsales@micropac.com 05/16/01 PRELIMINARY DATA SHEET 53248

28 VDC SOLID STATE HIGH SIDE SELF-PROTECTED POWER CONTROLLER

(POWER GND) Dimensions: inches PIN # FUNCTION SIGNAL GND POWER GND POWER GND

4 OUTPUT

5 OUTPUT

6 POWER IN

7 POWER IN

Micropac Industries cannot assume any responsibility for any circuits shown or represent that they are free from patent infringement. Micropac reserves the right to make changes at any time in order to improve design and to supply the best product possible. MICROPAC INDUSTRIES, INC. HYBRID MICROELECTRONICS PRODUCTS DIVISION • 905 E. Walnut St., Garland, TX 75040 • (972) 272-3571 • Fax (972) 494-2281 www.micropac.com E-MAIL: hybridsales@micropac.com 05/16/01 PRELIMINARY DATA SHEET 53248 (@ TC 25°C unless otherwise specified) Control Function Status Function Open Collector transistor, VCC = +40 VDC (max) Output High is VCC , Output Low is +0.4 V (max) @ ICC = 10 mA (max) Status output transistor off (logic high) indicates unit is off. Status output transistor on (V ≤ 0.4 VDC) indicates unit is on. Power Circuit Temperature Range Thermal Resistance Physical Characteristics See Package Configuration Timing at 28 VDC (IL =1A)

Micropac Industries cannot assume any responsibility for any circuits shown or represent that they are free from patent infringement. Micropac reserves the right to make changes at any time in order to improve design and to supply the best product possible. MICROPAC INDUSTRIES, INC. HYBRID MICROELECTRONICS PRODUCTS DIVISION • 905 E. Walnut St., Garland, TX 75040 • (972) 272-3571 • Fax (972) 494-2281 www.micropac.com E-MAIL: hybridsales@micropac.com 05/16/01 PRELIMINARY DATA SHEET 53248 The 53248 SSPC is a fully protected switch that offers a wide range of features. These include overvoltage and undervoltage shutdown with automatic reset, overcurrent and short circuit protection provided by temperature sensing with automatic reset when temperature drops to safe levels, built in transient protection and fully optically isolated control and status lines. The overcurrent and short circuit pr otection are achieved through the temperature-sensing feature of the controller. Overcurrent is sensed through the increasing R DS(ON) causing increase power dissipation in the pass element, wh ich additionally causes a further increase in R DS(ON). As junction temperature approaches +150°C, drive to the pass element is decreased, causing VDS to increase. When the pass element temperature is between +150°C and +175° C, the drive to the pass element is removed and current flow ceases. When the temperature is reduced approximately 10°C the device will resume operations. This will continue until the overcurrent/short circuit is removed or the control is turned off. Status will indicate the overcurrent condition until the fault is removed. Peak Current Limits vs. Junction Temperature* Overvoltage and Undervoltage Limits Junction Temperature Min Typ Max Unit Overvoltage +34 VDC to +43 VDC -40°C 48 56 65 A Undervoltage +3.4 VDC to +5.0 VDC +25°C 40 50 58 A Overvoltage hysteresis Typical +1.0 VDC +150°C 31 37 45 A Undervoltage hysteresis Typical +0.5 VDC (Tj = –40°C to +150°C) *Peak Duration - Typical Waveform Short Circuit Protection: Short-While-On Peak Duration @ 25°C -10 -20 0 20 40 60 80 100 Time (ms) Output Current (A)

Micropac Industries cannot assume any responsibility for any circuits shown or represent that they are free from patent infringement. Micropac reserves the right to make changes at any time in order to improve design and to supply the best product possible. MICROPAC INDUSTRIES, INC. HYBRID MICROELECTRONICS PRODUCTS DIVISION • 905 E. Walnut St., Garland, TX 75040 • (972) 272-3571 • Fax (972) 494-2281 www.micropac.com E-MAIL: hybridsales@micropac.com 05/16/01 PRELIMINARY DATA SHEET 53248

APPLICATION INFORMATION

The cable harness occupies an important position in the total network to be protected. The wide variety and in some cases considerable length and packing density us ed makes them particularly susceptible to persistent overloads and overheating. The maximum current carrying capacity of a cable depends on its resistance, type of insulation material and the ambient temperature. A cable, including insulation, generally consists of at least two materials with different thermal capacitance and thermal resistance. The maximum temperatures of most cables are at least +150°C (depending on the insulation properti es) which is very close to the maximum junction temperature of the SSPC (Shutdown). Since under overcurrent or short circuit conditions, the unit resistance per unit length for the cable is much less than the RDS of the SSPC, the unit heating will also be much less. Under these conditions, it is apparent that the SSPC can adequately protect properly selected cabling. The following formulas provide methods for calculating the primary parameters. Trip Current Itrip = {(Tj max – Ta)/[R θja ][RON (Tj max)]}1/2 Tj max = Maximum Trip Temperature R θja = Thermal Resistance, Junction to Ambient Ta = Ambient Temperature RON (Tj max) = On-state resistance at Trip Temperature On-state Resistance Y1 = RON at +25°C Y2 = RON at +150°C T = Tj at temperature of interest in °C With the above information, the temperature and current trip can be determined based upon the type of mounting chosen and the ambient temperatures of operation. Precaution When a short circuit causes turn-off of the SSPC, precautions must be taken to limit transient voltages generated by any inductance in the load. External protection is recommended, either across the switch or across the load, should the application result in energies beyond this level.

Micropac Industries cannot assume any responsibility for any circuits shown or represent that they are free from patent infringement. Micropac reserves the right to make changes at any time in order to improve design and to supply the best product possible. MICROPAC INDUSTRIES, INC. HYBRID MICROELECTRONICS PRODUCTS DIVISION • 905 E. Walnut St., Garland, TX 75040 • (972) 272-3571 • Fax (972) 494-2281 www.micropac.com E-MAIL: hybridsales@micropac.com 05/16/01 PRELIMINARY DATA SHEET 53248 H L H H L Current Limitation L H L H H Short circuit to Power Ground L H L L H Over-Temperature L H L L H Short circuit to Power In L H H H L L Undervoltage L H L L H H Overvoltage L H L L H H Note: L = “Low” Level H = “High” Level ** Status output will cycle between H and L while SSPC is in auto-reset mode. Loads The 53248 SSPC is designed to handle low side loads from +5 VDC to +33 VDC. Any combination of inductive, resistive and capacitive may be used. This includes lamps and DC motors. Inductive loads require protecting the SSPC from voltage transients as pointed out in the precaution section above. Charging Capacitive loads is generally not a problem due to the auto-reset feature of the current limit function. For capacitive loads, the user must assure that junction temperatures are not exceeded and at turn off if the VCC drops below the voltage charge on the capacitor, any current will flow through the body diode of the FET switch. Since this is a normal PN junction, the power dissipated for a given current can be many times that of the forward current through the FET. Incandescent lamps must be treated much like capacitive loads in that in-rush currents at turn-on can cause an overcurrent condition. DC motors must be treated like capacitive loads because in-rush currents can be very high. Should a machine continue to rotate after power is removed, reverse currents due to back EMF need to be addressed. Heatsinking The SSPC is designed to take advantage of the relationship between junction temperatures and heat sink thermal impedance. As described in the section discussing current trip characteristics, the thermal impedance of the heat sink utilized can determine the magnitude of over current or short circuit current expected in a system.

Micropac Industries cannot assume any responsibility for any circuits shown or represent that they are free from patent infringement. Micropac reserves the right to make changes at any time in order to improve design and to supply the best product possible. MICROPAC INDUSTRIES, INC. HYBRID MICROELECTRONICS PRODUCTS DIVISION • 905 E. Walnut St., Garland, TX 75040 • (972) 272-3571 • Fax (972) 494-2281 www.micropac.com E-MAIL: hybridsales@micropac.com 05/16/01 PRELIMINARY DATA SHEET 53248 The Power MOSFETs used in Micropac’s SSPC have very low on resistance and therefore low power dissipation. Typical on-state resistance at 25°C is only 27 mΩ. Due to internal design the typical VDS at 0.5 A is 50 mV. This stays relatively constant until the current reaches approximately 2 amperes when VDS is 60 mV. For higher currents, the RDS is constant at Tj of +25°C. Maximum RDS at +150°C is 70 mΩ. Since the design of SSPC current limit is temperature dependent, there is no need for a current sensing resistor and therefore no additional voltage drop which would add to the RDS. Isolation of Control and Status The SSPC was designed to utilize optical isolation both on the input/control and the status feed back. The only input power required is that necessary to drive a control LED and provide pull up power for the open collector status transistor. The SSPC derives its ener gy for operation from the 28 VDC load supply. As a result, the power in and power out are completely isolated.