4.5 Mbit synchronous ZBT SRAM — 10 ns access, 128K x 36 organization
The Renesas 71V547S100PFG is a 4.5 Mbit synchronous SRAM with a Zero Bus Turnaround (ZBT) architecture, organized as 128K words by 36 bits. The 10 ns access time supports bus operation at clock rates up to 100 MHz without wait states in most single-cycle read/write sequences. The 36-bit word width is a natural fit for systems that carry parity or ECC alongside a 32-bit datapath — common in network switches, base stations, and telecom line cards where data integrity matters.
Supply and temperature — design-in constraints
The supply range is 3.135 V to 3.465 V, a tight ±5% window around the nominal 3.3 V rail. That means the board's 3.3 V regulator needs to hold regulation within that band under load — a standard 3.3 V ±5% rail is fine, but a rail that droops to 3.0 V during transient events will violate the minimum. This part is not rated for industrial enclosures, outdoor cabinets, or under-hood environments. If your system sees -20°C or +85°C ambient, this is not the SRAM for that BOM.
Housed in a 100-pin LQFP (supplier device package 100-TQFP, 14x14 mm body). Keep the decoupling capacitors close to the supply pins; the synchronous switching edges draw transient currents that need a low-inductance path.