You need both. Do not substitute one for the other.
Use each component in the right way:
Equity
should be used in early rounds for R&D and product development
and in later rounds, for ramp-ups in sales and marketing and
acceleration purposes.
Debt
should be used for working capital, including any
personal loans, and to build the
infrastructure.
Debt
usually follows equity.
Debt is cheaper than equity but always keep in mind that the
equity investors take greater risk, hence the potential for reward
should be greater.
The sooner you
establish a banking relationship, the better. It increases
credibility and also creates a relationship for credit reference
purposes.