QB210T Normally-Closed QBAR® Switch  
Description

QBAR® ICs provide a 3-terminal semiconductor switch that functions as:

  • a solid-state normally closed switch
  • a non-inverting digital transistor
  • a solid-state replacement for a normally-closed non-isolating relay

QBAR® ICs do not require a separate power supply lead. This makes possible:

  • simplified control wiring
  • replacement of normally-closed D.C. relays with highly reliable solid-state devices
  • improved fail-safe performance in the event of lost control power, severed or shorted control wires

 3 Amperes
 20 Volts
 TO-220 package 		  PIN
 1 INPUT
 2 GND
 3 OUTPUT 
 4 GND
QBAR Switch Symbol

 Functional Schematic

 Function Table
INPUT

SWITCH-STATE
(output-to-gnd)
HI OFF
LO ON
OPEN ON
Typical Applications

Alarm Switch

A QBAR® switch activates an alarm over a large range of system failure conditions:

  • system failure indicated by a LO on the status output
  • status conductor cut
  • status conductor shorted to ground
  • loss of +5 V supply

Any of these conditions will cause the QBAR® switch to turn ON and power the alarm.

Protections of Fragile or Trigger Devices

A QBAR® switch protects the load from being driven by false signals when all status indicators are not OK. Damage to fragile loads such as laser diodes, or erroneous firing of detonators can be avoided with a QBAR® switch. It shunts drive current I around the load when any Status Gate input goes LO, when +5 V power is lost, or when the conductor from the Status Gate output to QBAR® switch input is cut or shorted to ground.

 

Power Supply Efficiency Boost

Increase your power supply efficiency by using a QBAR® switch to lower the parasitic current drain through the bleeder resistor during normal supply operations.

Absolute Maximum Ratings QB210T

Voltage, output to ground......................................24 V  
Voltage, input to ground....................................... +6 V  
Ambient Operating Temperature Range......0°C to 70°C  
Storage Temperature Range.................-55°C to 150°C  
Output current, continuous.......................................3 A  

Electrical Specifications (over full operating temperature range, unless noted)

Parameter Conditions MIN TYP MAX UNITS
OFF Characteristics          
Output Breakdown Voltage V input > 2.4 V 20     V
  I output < 750µA        
Output OFF Current V input > 2.4 V   +300 +750 µA
  V output = 20 V        
Input HIGH Logic Threshold     1.7 2.4 V
Input HIGH Input Current V input = 2.4 V 0   +60 µA
ON Characteristics          
Output ON Voltage V input < 0.8 V        
  I output = 1.80 A   1.3 1.8 V
Input LOW Logic Threshold   0.8 1.4   V
Input LOW Input Current -6 < V input < 0.8 V -20   +20 µA
Input Logic Threshold Hysteresis   0.1     V
SWITCHING Characteristics          
Turn-on Time, Turn-off Time V in0 = 0.8 V   2 5 µs
  V in1 = 2.4 V        
  V cc = 12 V        
  I out = 50 mA        
  Notes:
1. When not connected, the Input Terminal floats LOW, putting the QBAR® switch in the ON state. Nevertheless, for minimum noise susceptibility, input should be connected to valid logic levels.
2. BitParts Inc.'s products are protected by U.S. patents 5,134,323; 6,259,252; 6,639,777; 6,958,623; foreign patents issued and pending.

 

Packaging Options:
Package Marking Suffix Order No.
TO-220 QB210T
WWYY		 T QB210T
See bitpartsinc.com or Contact BitParts Inc. for more information or other packaging options.


BitParts Inc, reserves the right to make changes without further notice to these components to improve reliability, function, or design. BitParts, Inc. assumes no liability arising from the use of these components. The products of BitParts, Inc. are not intended for use in life support appliances, devices, or systems. Use of a BitParts, Inc. product in such applications without the written consent of the President of BitParts, Inc. is prohibited. QBAR is a registered trademark of BitParts, Inc.

Copyright © BitParts Incorporated 1997-2007
 
P.O. Box 617
Sudbury, MA 01776

Phone: (978)443-5720
Fax: (978)443-5744
info@bitpartsinc.com