Thanks John! That is very helpful! So to avoid unwanted lit, what should I do? Can I just put a diode there to prevent the chip sourcing the bulb?
On Saturday, April 18, 2015 at 10:13:40 AM UTC-4, jrehwin wrote: > > > On Apr 18, 2015, at 4:06 AM, Chaos Hydra <[email protected] <javascript:>> > wrote: > > > Hello! First time post here. So I am doing a nixie clock with IN-12 and > KM155ID1 mux chip. > > The KM155ID1 is a nixie driver, not really a "mux chip", although it can > certainly be used in multiplex designs. > > > To ensure the look, I decided to use INS-1 neon bulb to do the little > colons between the digits. My questions is: can I drive the INS-1 bulb as I > did to IN-12? With an 220k current limiting resistor under 170VDC, the INS > bulb got 5mA. Considering IN-12 has 6mA without current limiting resistor, > I think I can just use K155ID1 to sink in the current and control the neon > bulbs. > > Yes, the chip won't mind at all. However, due to the clamp diodes, the > "off" voltage is about 100V (60V for the US equivalent). With an ordinary > nixie this is fine as long as another cathode is lit. However, > for individual bulbs and nixies without any cathodes lit, that's enough > voltage across the tube to possibly cause some unwanted glow. > > > Consider I give most of my knowledge of digital parts' parameter back to > professors, can any one please point out on the data sheet: when I am > sinking current into the active low pin(to turn on an bulb or a single > filament in nixie), which value is the maximum current? > > That does not appear to be given on the data sheet, however, it does say > that when sinking 7mA, the voltage on an output pin will not exceed 2.5V, > so 7mA is allowed by implication. > > - John > > On Saturday, April 18, 2015 at 10:13:40 AM UTC-4, jrehwin wrote: > > > On Apr 18, 2015, at 4:06 AM, Chaos Hydra <[email protected] <javascript:>> > wrote: > > > Hello! First time post here. So I am doing a nixie clock with IN-12 and > KM155ID1 mux chip. > > The KM155ID1 is a nixie driver, not really a "mux chip", although it can > certainly be used in multiplex designs. > > > To ensure the look, I decided to use INS-1 neon bulb to do the little > colons between the digits. My questions is: can I drive the INS-1 bulb as I > did to IN-12? With an 220k current limiting resistor under 170VDC, the INS > bulb got 5mA. Considering IN-12 has 6mA without current limiting resistor, > I think I can just use K155ID1 to sink in the current and control the neon > bulbs. > > Yes, the chip won't mind at all. However, due to the clamp diodes, the > "off" voltage is about 100V (60V for the US equivalent). With an ordinary > nixie this is fine as long as another cathode is lit. However, > for individual bulbs and nixies without any cathodes lit, that's enough > voltage across the tube to possibly cause some unwanted glow. > > > Consider I give most of my knowledge of digital parts' parameter back to > professors, can any one please point out on the data sheet: when I am > sinking current into the active low pin(to turn on an bulb or a single > filament in nixie), which value is the maximum current? > > That does not appear to be given on the data sheet, however, it does say > that when sinking 7mA, the voltage on an output pin will not exceed 2.5V, > so 7mA is allowed by implication. > > - John > > On Saturday, April 18, 2015 at 10:13:40 AM UTC-4, jrehwin wrote: > > > On Apr 18, 2015, at 4:06 AM, Chaos Hydra <[email protected] <javascript:>> > wrote: > > > Hello! First time post here. So I am doing a nixie clock with IN-12 and > KM155ID1 mux chip. > > The KM155ID1 is a nixie driver, not really a "mux chip", although it can > certainly be used in multiplex designs. > > > To ensure the look, I decided to use INS-1 neon bulb to do the little > colons between the digits. My questions is: can I drive the INS-1 bulb as I > did to IN-12? With an 220k current limiting resistor under 170VDC, the INS > bulb got 5mA. Considering IN-12 has 6mA without current limiting resistor, > I think I can just use K155ID1 to sink in the current and control the neon > bulbs. > > Yes, the chip won't mind at all. However, due to the clamp diodes, the > "off" voltage is about 100V (60V for the US equivalent). With an ordinary > nixie this is fine as long as another cathode is lit. However, > for individual bulbs and nixies without any cathodes lit, that's enough > voltage across the tube to possibly cause some unwanted glow. > > > Consider I give most of my knowledge of digital parts' parameter back to > professors, can any one please point out on the data sheet: when I am > sinking current into the active low pin(to turn on an bulb or a single > filament in nixie), which value is the maximum current? > > That does not appear to be given on the data sheet, however, it does say > that when sinking 7mA, the voltage on an output pin will not exceed 2.5V, > so 7mA is allowed by implication. > > - John > > On Saturday, April 18, 2015 at 10:13:40 AM UTC-4, jrehwin wrote: > > > On Apr 18, 2015, at 4:06 AM, Chaos Hydra <[email protected] <javascript:>> > wrote: > > > Hello! First time post here. So I am doing a nixie clock with IN-12 and > KM155ID1 mux chip. > > The KM155ID1 is a nixie driver, not really a "mux chip", although it can > certainly be used in multiplex designs. > > > To ensure the look, I decided to use INS-1 neon bulb to do the little > colons between the digits. My questions is: can I drive the INS-1 bulb as I > did to IN-12? With an 220k current limiting resistor under 170VDC, the INS > bulb got 5mA. Considering IN-12 has 6mA without current limiting resistor, > I think I can just use K155ID1 to sink in the current and control the neon > bulbs. > > Yes, the chip won't mind at all. However, due to the clamp diodes, the > "off" voltage is about 100V (60V for the US equivalent). With an ordinary > nixie this is fine as long as another cathode is lit. However, > for individual bulbs and nixies without any cathodes lit, that's enough > voltage across the tube to possibly cause some unwanted glow. > > > Consider I give most of my knowledge of digital parts' parameter back to > professors, can any one please point out on the data sheet: when I am > sinking current into the active low pin(to turn on an bulb or a single > filament in nixie), which value is the maximum current? > > That does not appear to be given on the data sheet, however, it does say > that when sinking 7mA, the voltage on an output pin will not exceed 2.5V, > so 7mA is allowed by implication. > > - John > > On Saturday, April 18, 2015 at 10:13:40 AM UTC-4, jrehwin wrote: > > > On Apr 18, 2015, at 4:06 AM, Chaos Hydra <[email protected] <javascript:>> > wrote: > > > Hello! First time post here. So I am doing a nixie clock with IN-12 and > KM155ID1 mux chip. > > The KM155ID1 is a nixie driver, not really a "mux chip", although it can > certainly be used in multiplex designs. > > > To ensure the look, I decided to use INS-1 neon bulb to do the little > colons between the digits. My questions is: can I drive the INS-1 bulb as I > did to IN-12? With an 220k current limiting resistor under 170VDC, the INS > bulb got 5mA. Considering IN-12 has 6mA without current limiting resistor, > I think I can just use K155ID1 to sink in the current and control the neon > bulbs. > > Yes, the chip won't mind at all. However, due to the clamp diodes, the > "off" voltage is about 100V (60V for the US equivalent). With an ordinary > nixie this is fine as long as another cathode is lit. However, > for individual bulbs and nixies without any cathodes lit, that's enough > voltage across the tube to possibly cause some unwanted glow. > > > Consider I give most of my knowledge of digital parts' parameter back to > professors, can any one please point out on the data sheet: when I am > sinking current into the active low pin(to turn on an bulb or a single > filament in nixie), which value is the maximum current? > > That does not appear to be given on the data sheet, however, it does say > that when sinking 7mA, the voltage on an output pin will not exceed 2.5V, > so 7mA is allowed by implication. > > - John > > On Saturday, April 18, 2015 at 10:13:40 AM UTC-4, jrehwin wrote: > > > On Apr 18, 2015, at 4:06 AM, Chaos Hydra <[email protected] <javascript:>> > wrote: > > > Hello! First time post here. So I am doing a nixie clock with IN-12 and > KM155ID1 mux chip. > > The KM155ID1 is a nixie driver, not really a "mux chip", although it can > certainly be used in multiplex designs. > > > To ensure the look, I decided to use INS-1 neon bulb to do the little > colons between the digits. My questions is: can I drive the INS-1 bulb as I > did to IN-12? With an 220k current limiting resistor under 170VDC, the INS > bulb got 5mA. Considering IN-12 has 6mA without current limiting resistor, > I think I can just use K155ID1 to sink in the current and control the neon > bulbs. > > Yes, the chip won't mind at all. However, due to the clamp diodes, the > "off" voltage is about 100V (60V for the US equivalent). With an ordinary > nixie this is fine as long as another cathode is lit. However, > for individual bulbs and nixies without any cathodes lit, that's enough > voltage across the tube to possibly cause some unwanted glow. > > > Consider I give most of my knowledge of digital parts' parameter back to > professors, can any one please point out on the data sheet: when I am > sinking current into the active low pin(to turn on an bulb or a single > filament in nixie), which value is the maximum current? > > That does not appear to be given on the data sheet, however, it does say > that when sinking 7mA, the voltage on an output pin will not exceed 2.5V, > so 7mA is allowed by implication. > > - John > > On Saturday, April 18, 2015 at 10:13:40 AM UTC-4, jrehwin wrote: > > > On Apr 18, 2015, at 4:06 AM, Chaos Hydra <[email protected] <javascript:>> > wrote: > > > Hello! First time post here. So I am doing a nixie clock with IN-12 and > KM155ID1 mux chip. > > The KM155ID1 is a nixie driver, not really a "mux chip", although it can > certainly be used in multiplex designs. > > > To ensure the look, I decided to use INS-1 neon bulb to do the little > colons between the digits. My questions is: can I drive the INS-1 bulb as I > did to IN-12? With an 220k current limiting resistor under 170VDC, the INS > bulb got 5mA. Considering IN-12 has 6mA without current limiting resistor, > I think I can just use K155ID1 to sink in the current and control the neon > bulbs. > > Yes, the chip won't mind at all. However, due to the clamp diodes, the > "off" voltage is about 100V (60V for the US equivalent). With an ordinary > nixie this is fine as long as another cathode is lit. However, > for individual bulbs and nixies without any cathodes lit, that's enough > voltage across the tube to possibly cause some unwanted glow. > > > Consider I give most of my knowledge of digital parts' parameter back to > professors, can any one please point out on the data sheet: when I am > sinking current into the active low pin(to turn on an bulb or a single > filament in nixie), which value is the maximum current? > > That does not appear to be given on the data sheet, however, it does say > that when sinking 7mA, the voltage on an output pin will not exceed 2.5V, > so 7mA is allowed by implication. > > - John > > On Saturday, April 18, 2015 at 10:13:40 AM UTC-4, jrehwin wrote: > > > On Apr 18, 2015, at 4:06 AM, Chaos Hydra <[email protected] <javascript:>> > wrote: > > > Hello! First time post here. So I am doing a nixie clock with IN-12 and > KM155ID1 mux chip. > > The KM155ID1 is a nixie driver, not really a "mux chip", although it can > certainly be used in multiplex designs. > > > To ensure the look, I decided to use INS-1 neon bulb to do the little > colons between the digits. My questions is: can I drive the INS-1 bulb as I > did to IN-12? With an 220k current limiting resistor under 170VDC, the INS > bulb got 5mA. Considering IN-12 has 6mA without current limiting resistor, > I think I can just use K155ID1 to sink in the current and control the neon > bulbs. > > Yes, the chip won't mind at all. However, due to the clamp diodes, the > "off" voltage is about 100V (60V for the US equivalent). With an ordinary > nixie this is fine as long as another cathode is lit. However, > for individual bulbs and nixies without any cathodes lit, that's enough > voltage across the tube to possibly cause some unwanted glow. > > > Consider I give most of my knowledge of digital parts' parameter back to > professors, can any one please point out on the data sheet: when I am > sinking current into the active low pin(to turn on an bulb or a single > filament in nixie), which value is the maximum current? > > That does not appear to be given on the data sheet, however, it does say > that when sinking 7mA, the voltage on an output pin will not exceed 2.5V, > so 7mA is allowed by implication. > > - John > > On Saturday, April 18, 2015 at 10:13:40 AM UTC-4, jrehwin wrote: > > > On Apr 18, 2015, at 4:06 AM, Chaos Hydra <[email protected] <javascript:>> > wrote: > > > Hello! First time post here. So I am doing a nixie clock with IN-12 and > KM155ID1 mux chip. > > The KM155ID1 is a nixie driver, not really a "mux chip", although it can > certainly be used in multiplex designs. > > > To ensure the look, I decided to use INS-1 neon bulb to do the little > colons between the digits. My questions is: can I drive the INS-1 bulb as I > did to IN-12? With an 220k current limiting resistor under 170VDC, the INS > bulb got 5mA. Considering IN-12 has 6mA without current limiting resistor, > I think I can just use K155ID1 to sink in the current and control the neon > bulbs. > > Yes, the chip won't mind at all. However, due to the clamp diodes, the > "off" voltage is about 100V (60V for the US equivalent). With an ordinary > nixie this is fine as long as another cathode is lit. However, > for individual bulbs and nixies without any cathodes lit, that's enough > voltage across the tube to possibly cause some unwanted glow. > > > Consider I give most of my knowledge of digital parts' parameter back to > professors, can any one please point out on the data sheet: when I am > sinking current into the active low pin(to turn on an bulb or a single > filament in nixie), which value is the maximum current? > > That does not appear to be given on the data sheet, however, it does say > that when sinking 7mA, the voltage on an output pin will not exceed 2.5V, > so 7mA is allowed by implication. > > - John > > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send an email to [email protected]. 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