Novelty musical toy power issue and unknown component

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  • looxuser
    New Member
    • Apr 2021
    • 4
    • United Kingdom
    #1

    Novelty musical toy power issue and unknown component

    Hello everyone, I have a device which moves little motorised characters to music however i cannot get it to start up. I've attached the circuit diagram I've prepared to explain where i'm struggling. In the diagram you can see that the main power routes through a PNP driver transistor to derrive 5volts on the VCC. The base of the transistor is supplied from IC13 which is a sot23-5 marked "504"or "50B". What i'm falling to understand is how this device can reduce the voltage on the collector to that VCC voltage? As it happens i am unlikely to be able to source that IC I suspect is faulty, so can anyone suggest how i circumvent it to provide enough power through the transisitor at 6v VCC to pwoer that step up converter and the main system 12v rail please?
    https://i.stack.imgur.com/HyLJe.jpg

    Note the IC13 symbol is wrong I believe its a RN5RF50AA by Ricoh
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