Ron Conway, one of San Francisco's top tech power brokers, is taking a step back from tech investing.

SV Angel, an early-stage venture capital firm founded by Conway, said Thursday it won't be raising another fund.

Conway and his son Topher will continue to invest under the SV Angel name, on a smaller scale and with their own personal funds, according to a blog post announcing the scaling back.

"The amount of money raised in seed rounds has doubled and valuations have increased significantly," the post reads. "As we thought about how best to serve founders in this environment, we also realized we no longer need to write big checks in order to help."

Capital has flooded into Silicon Valley in recent years, bolstered in part by investing machines like Japanese conglomerate SoftBank. Tech start-ups are posting sky-high valuations and delaying IPOs.

"Writing smaller checks allows us to stay true to our DNA, remain nimble and fulfill our commitment to supporting founders," the SV Angel team wrote. "We know that if we continue to get behind the right people, success for us and the founders we support will follow."

SV Angel counts early-stage investments in tech giants like Twitter, Pinterest, Airbnb and Square. General partners at the firm Brian Pokorny, Kevin Carter and Robert Pollak will move into advising roles.