Shift Register 74HC595 Voltage Drop

hello,

please check circuit below.

if transistors out of circuit (just testing purposes) shift registers outputs reaches 5v.

if transistors in circuit (without load/leds) the shift registers outputs drops 1v.

the transistors bd139.

should use resistor shift register outputs transistors bases?




thanks

you're massively overloading 595's outputs shorting them ground
through transistors base-emitter junction (which behaves forward
baised diode).

you need base resistor each transistor, limit current to
something sensible (within capability of hc595's outputs).

what current hoping drive via bd139's?  don't have gain
and 74hc family can't put current base in first place.

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