1222 Tuner VCO Module

Yeah, pulse is +Vcc minus voltage drop over the output transistor (which depends on current, but is nominally +Vcc−1.5V), while triangle output is fixed at +Vcc/3 (so 4 V with a 12 V supply) and any non-trivial load will affect the tuning (so you really want a buffer on that one). Ramp/sawtooth is +Vcc×2/3 (8 V), with more internal buffering.

(there may be an argument for turning triangle or ramp into PWM outside the chip to make things more stable, cf the AS3340-HYB variant discussed here, but haven’t experimented with that);

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