CD4050B: Consumption

Farzaneh Faridi

Part Number: CD4050B

Dear members

In our digital signal conditioning application we use the hex inverting buffer CD4050BPW_SMD. What happens, is that if we apply simultaneously to the 6 outputs a consumption of 3.5mA, some devices are damaged. What is the maximum output current per gate? What is the maximum total current that the device can provide?

I appreciate any kind of help

Farzaneh

over 1 year ago

0 Clemens Ladisch over 1 year ago

Guru 317060 points

What is the supply voltage?

0 Farzaneh Faridi over 1 year ago in reply to Clemens Ladisch

Intellectual 615 points

Hello Clemens,

The supply voltage is 12V

0 Clemens Ladisch over 1 year ago in reply to Farzaneh Faridi

Guru 317060 points

Figure 6-5 shows a typical voltage drop of 0.5 V, so the power dissipation is about 6 × 0.5 V × 3.5 mA = 10.5 mW, and the temperature increase is about 10.5 mW × 108.4 °C/W = 1.1 °C above ambient. This is negligible.

Are you using high-frequency signals, and long traces/cables with a high capacitive load? In that case, the current will be much higher.

0 Albert Xu1 over 1 year ago in reply to Clemens Ladisch

TI__Mastermind 38165 points

Hi Farzaneh,

I agree with Clemens, I would double check if it is actually 3.5mA going through. Can you send over a schematic?

0 Farzaneh Faridi over 1 year ago in reply to Clemens Ladisch

Intellectual 615 points

You can find the circuit of each buffer in the SCH. The frequency of the signal is 80KHz.

0 Malcolm Lyn over 1 year ago in reply to Farzaneh Faridi

TI__Mastermind 26250 points

Hi Farzaneh,

Does that say 1 meter? If so that cable is probably introducing a lot of capacitance to the output load of the device which is the reason for the excess current/damage to the device.

I'd try to move the serial resistor component of the voltage divider closer to the output (before the 1m cable). Or add a small 33-50 ohm resistor in series with the output, also before the cable. This should limit the current enough to prevent the device from being damaged.

Best,

Malcolm

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CD4050B: Consumption