Solar Biotranic Laboratories Private Limited

These keypads incorporate a moulded silicon layer which sits on a PCB assembled with snap dome switches (see diagram).

The basic specifications are similar to the Snap Dome Keyboards and the main difference is that the Overlay is made of Silicon Rubber in place of Polyester.

In order to get the best Cost Benefit Ratio for Silicon Rubber Keypads, off takes should be relatively high
(> 10000 nos per annum). This is because a die mould is required for achieving the emboss and shape of the silicon layer.

Features:

The Solar Biotronic Laboratories Silicon Rubber Keypads offers the following features:

• Gold plated contacts for superior switch performance.
• Industrial grade adhesives used to withstand harsh environmental factors.
• Silicon Rubber Overlay used to withstand harsh environment.
• Overlay legends can be printed on keys as per Customer's requirements.
• Can accomodate LEDs / Components thus saving space inside the equipment.

Specifications:
Electrical:            

• Contact Arrangement  : SPST Normally Open
• Current / Voltage Rating :10 mA at 24 VDC (max) in to resistive load only
• Contact Resistance : Compatible with MOS, TTL & DTL Circuits
• Contact Bounce : Less than 10 milliseconds at make & 20 milliseconds at break                
  

Mechanical:

• Operating Temperature : -20oC to + 65oC
• Key Travel : 380 microns
• Life expectancy: One million to Three million operations
• Operating Temperature  : -20 deg to 65 deg centigrade
• Humidity : 95% RH at 40oC

Materials:

• Base :Glass Epoxy PCB FR4 Grade in thickness ranging from 0.4 mm to 3.2 mm
• Plating : Bright Acid Tin; Nickel, Gold over Nickel
• Adhesives : Industrial Grade from 3M , Avery Dennision
• Overlays : Silicon Rubber

These keyboards comprise of a Snap Dome Switch and glass epoxy PCB which is used as a base and for the circuit. (See photograph) A layer of Polyester or Polycarbonate covers and seals this assembly using Industrial Grade Adhesives made by preparers like 3M, Avery Dennison, etc. These type of sealed keyboards can be offered in any size and shape and are made as per customer's specifications and requirements.

These keyboards can also accommodate LEDs of various colours and shapes. Any solderable type of connector like Berg strips, FRC, Relimate, D Type etc. can be provided.

Features:

• Gold plated contacts for superior switch performance.
• Industrial grade adhesives used to withstand harsh environmental factors.
• Polyester Overlay used to withstand even Industrial solvents.
• Overlay legends can be printed on keys as per Customer's requirements.
• Can accomodate LEDs / Components thus saving space inside the equipment.

Electrical:                

• Contact Arrangement : SPST Normally Open
• Current / Voltage Rating  : 10 mA at 24 VDC (max) in to resistive load only
• Contact Resistance :  Compatible with MOS, TTL & DTL Circuits
• Contact Bounce : Less than 10 milliseconds at make & 20 milliseconds at break                

Mechanical:                

• Operating Temperature : -20oC to + 65oC
• Key Travel : 380 microns
• Life expectancy :  One million to Three million operations
• Operating Temperature :  -20 deg to 65 deg centigrade     
  
• Humidity : 95% RH at 40oC                  
  

Materials:                

• Base : Glass Epoxy PCB FR4 Grade in thickness ranging from 0.4 mm to 3.2 mm
• Plating : Bright Acid Tin; Nickel, Gold over Nickel
• Adhesives : Industrial Grade from 3M , Avery Dennision
• Overlays : Polycarbonate - Lexan; Polyester - Autotex

Solar Biotronic Laboratories Private Limited, (SBL) offers Capacitive Switches with infinite life.

The working of these switches is based on Charge Detector (CD) technology. When any user touches the key / switch area the capacitive charge from the user’s body is detected by a specially developed circuit, and the signal is passed on to the system. The solid state nature of the circuit makes the life of such a switch virtually infinite.

As a result, such keyboards are very much suited for harsh environments, where switch abuse, use of dirty hands is a common practice.

The switches can be offered on any dielectric materials like glass, plastics, wood, granite, etc.

• Toggle Switching Operations
• Pulsed Operation
• Direct interface of switches with User's system via UART / I2C / RS 232 / Parallel ports etc.
• Back lit switches
• In built LED Driver for visual feedback which saves user end I/O ports
• Switch Operation through any dielectric like Glass, Wood, Granite, Tiles, Plastics, etc.
• Security Systems
• Elevator Buttons
• Bio-medical Applications
• Indicator Switches
• IP grade Applications

Besides the above, keyboards can be designed as per customers' requirements with reference to size, number of switches, graphic overlay, circuit parameters, interface connectors, etc.
     
Electrical

• Supply Voltage : 5-24 VDC
• Output : NPN/PNP/Relay contact/ UART/I2C/RS232/Parallel port
• Bounce / Debounce time : Nil
• Contact Resistance : Nil
• Function : Momentary /Latching                       
  

Mechanical

• Actuating Force : Finger Touch
• Operating Temp. : -20oC to +85oC

Most industrial processes are now controlled by computer systems. All such computers used are usually located in Shop Floor environments, which by any standards tend to be unclean. Normal switch keyboards used to operate such systems are always affected by the harsh environments in the Shop Floor area.

Solar Biotronic Laboratories therefore offers a Sealed PC compatible keyboard which can withstand these harsh conditions prevailing on Shop Floors or other areas.

The Keyboard is similar in construction to the Snap Dome Sealed Keyboard or the Low Profile Push Button Keyboard. It is housed in an IP55 grade enclosure and can be used as a desk top device. Keyboards with out enclosures can also be provided for direct assembly on the Panels.Besides the standard 104 switch keyboard (with Trackpad) Solar Biotronic Laboratories can also customize the layouts and size of such keyboards (See picture above). Solar Biotronic Laboratories also offers the freedom of using customized ASCII codes

Features:

Replaces the normal ASCII Keyboard with respect to the software, dimensions, circuits, legends, etc. No complicated fitments or programming is required.

1. Just plug in the socket into the Keyboard port and it's ready to use!
2. ESD/EMI field protections using shielding techniques and Online filters.
3. Clock frequencies generated using crystals for reliable operations.
4. Industrial grade components used to withstand harsh environments.
5. Multiple data entry protection provided. Auto reset facility offered.
6. IP55 Grade Enclosure.
7. Polyester Overlay used to withstand even Industrial solvents.
8. Industrial grade adhesives used to withstand harsh environmental factors.
9. DIN/PS2/USB type Connector options available.
10. Function Keys can be programmed as per Customer's requirements.
11. Additional function keys can be offered.
12. Overlay legends can be printed on keys as per Customer's requirements.
13. Can be offered with a standard enclosure or can be even rack mounted.

Specifications:

(For Standard Version – 104 or 84 keys with Trackpad)

These Keyboards comprise of low profile mechanical switches assembled on a PCB. This assembly is then mounted behind a front plate on which the polyester / polycarbonate Overlay is stuck.

These low profile switches have a lower operating pressure than Snap Domes (about 160 gF) and can be used in applications where the user needs to make larger data entries. The lower operating pressure makes it easier for the user to operate the keys. The total assembly height in such cases ranges between 12 to 15 mm. Switches manufactured by Schurter, Rafi, Omron and Diptronics, are used for such applications.

These keyboards can also accommodate LEDs of various colours and shapes. In fact low profile mechanical switches can also be offered backlit versions. Any solderable type of connector like Berg strips, FRC, Relimate, D Type etc. can be provided.

Here again as in Snap Dome keyboards, sealing can be achieved using industrial grade adhesives and such keyboard panels can be used in Machine Tool applications also.

Specifications:

Switch specifications for all the above mentioned low profile switches made by Schurter, Rafi, Omron, Diptronics etc., can be provided as required.