Many integrated circuits have undocumented features or abilities. This is one of them. The TLC555 output (pin 3) can sink a 100mA load to 1.28V. The open drain transistor reset (pin 7) can sink 100mA ...
The ULN2003V12 is a low power upgrade of TI’s popular ULN2003 family of 7-channel Darlington transistor array. The ULN2003V12 sink driver features 7 low output impedance drivers that minimize on-chip ...