SAN JOSE — The tech boom in Silicon Valley has spurred proposals for new high-rise projects in downtown San Jose that will bring housing, offices and retail, developers said Monday.

At 225 W. Julian St. near Highway 87, developers are planning a pair of 20-story residential towers that would bring 910 residential units into downtown San Jose, along with offices and retail uses. Nearby, developers want to build a 19-story office tower totaling 725,000 square feet at 333 W. San Fernando St. in a development that would also include retail uses on the ground floor.

The technology boom and job gains in North San Jose and other parts of Silicon Valley, along with growing interest by tech companies to move into the increasingly busy downtown, has fueled both efforts.

“If you look at what is happening here, downtown San Jose has really changed, and we are close to a tipping point for downtown becoming very dynamic,” said Mark Lazzarini, managing principal with DAL Properties, which believes its efforts at 222 W. Julian St. could ride that new wave.

More than any other factor, the remarkable surge in technology hiring by big tech companies such as Apple and Google, along with major players such as Samsung, have helped bolster plans by real estate developers to bring new projects into the downtown.

“We believe we can get a single tenant in our project” at 333 W. San Fernando St., said John DiNapoli, president of developer J.P. DiNapoli Cos. “We think this can be a tech tenant.”

The 333 W. San Fernando complex will feature an amenity deck on the 18th floor of the tower, an outdoor level that is expected to appeal to technology tenants.

“You have so many more restaurants, hotels, along with entertainment and cultural activities, that downtown San Jose is becoming the place to live, work and play,” Lazzarini said.

Another major effort to bring a tech company into new offices in downtown San Jose is being led by developer Trammell Crow. The realty firm is planning 1 million square feet of offices, housing and retail that will include a tech campus for a major tenant in a development planned for an area near the Guadalupe River not far from the SAP sports complex and the Diridon transit station.

San Jose’s expansion efforts, led by former Mayor Chuck Reed and current Mayor Sam Liccardo, appear to be paying off for the downtown district.

“The city has created a job center in North San Jose, and the development and expansion activity there is making it more difficult for tech companies to find large blocks of space there,” said Mark Haney, a blogger who writes about the downtown at the Think Bigger San Jose website.

The other part of the city’s strategy is to encourage multiple kinds of development in downtown San Jose.

“For downtown, the challenge is what would be first, the companies or the residences,” Haney said. “The residences have been built and are being built, and now it’s starting to pencil out for developers to build offices for tech tenants.”

What’s more, the tech boom and residential boom in San Francisco’s downtown and South of Market districts — along with the move of tech firms such as Pandora Media, Sungevity and Uber Technologies — has made urban centers more appealing to young tech workers.

“People are finding it more interesting to live in downtown areas,” Haney said.

Contact George Avalos at 408-859-5167. Follow him at Twitter.com/georgeavalos.