Technical Summary: Hitachi HM628512BI 4-Mbit SRAM

Overview

The Hitachi HM628512BI is a high-performance 4-Mbit static RAM (SRAM) organized as 512k words × 8 bits. Manufactured using advanced Hi-CMOS process technology, this component achieves higher density, improved performance, and reduced power consumption compared to conventional SRAM solutions. The HM628512BI is particularly well-suited for battery backup systems due to its ultra-low standby power dissipation. It is available in multiple package options, including 32-pin SOP, 32-pin TSOP II, and 32-pin DIP, making it versatile for various design requirements.

Features

• Single 5V Supply: Simplifies power management in embedded systems.
• High-Speed Access: Maximum access times of 70 ns or 85 ns, depending on the variant.
• Low Power Consumption:
  • Active mode: Typically 50 mW/MHz.
  • Standby mode: Typically as low as 10 µW, ideal for battery-operated applications.
• Fully Static Operation: No clock or timing strobes required, simplifying system design.
• Equal Access and Cycle Times: Ensures predictable performance in read/write operations.
• Three-State Output: Common data input and output with high-impedance state for bus sharing.
• TTL Compatibility: All inputs and outputs are directly compatible with TTL logic levels.
• Battery Backup Capability: Maintains data integrity during power loss.
• Wide Operating Temperature Range: -40°C to +85°C, suitable for industrial and automotive applications.

Applications

The HM628512BI is designed for a wide range of applications requiring reliable, high-speed, and low-power static memory. Key application areas include:

• Battery-Powered Systems: Portable devices, medical equipment, and IoT nodes benefit from its ultra-low standby power.
• Embedded Systems: Microcontroller-based designs requiring fast, non-volatile memory.
• Industrial Control Systems: Robust operation across a wide temperature range ensures reliability in harsh environments.
• Automotive Electronics: Infotainment systems, engine control units, and other critical subsystems.
• Telecommunications: Buffering and temporary storage in networking equipment.
• Consumer Electronics: Gaming consoles, printers, and other devices requiring high-speed data access.

Electrical Characteristics

Absolute Maximum Ratings

• Supply Voltage (Vcc): -0.5V to +7.0V
• Input Voltage (Vin): -0.5V to Vcc + 0.5V
• Output Voltage (Vout): -0.5V to Vcc + 0.5V
• Operating Temperature Range (Topr): -40°C to +85°C
• Storage Temperature Range (Tstg): -65°C to +150°C

Recommended Operating Conditions

• Supply Voltage (Vcc): 4.5V to 5.5V
• Input High Voltage (VIH): 2.2V min (Vcc = 4.5V)
• Input Low Voltage (VIL): 0.8V max (Vcc = 4.5V)
• Output High Voltage (VOH): 2.4V min (Ioh = -2.0 mA)
• Output Low Voltage (VOL): 0.4V max (Iol = 2.0 mA)

Power Consumption

• Active Current (Icc): 50 mA max (f = 1 MHz, Vcc = 5V)
• Standby Current (Isb): 10 µA max (Vcc = 3V, CMOS level)

Package Information

The HM628512BI is available in three industry-standard packages, providing flexibility for different PCB layouts and space constraints:

32-Pin SOP (Small Outline Package)

• Dimensions: 20.0 mm × 10.0 mm × 2.65 mm (max)
• Pin Pitch: 1.27 mm
• Package Code: PRSP0032GA-A

32-Pin TSOP II (Thin Small Outline Package Type II)

• Dimensions: 20.0 mm × 8.0 mm × 1.2 mm (max)
• Pin Pitch: 0.8 mm
• Package Code: PTTF0032GA-A

32-Pin DIP (Dual In-line Package)

• Dimensions: 42.0 mm × 10.0 mm × 3.5 mm (max)
• Pin Pitch: 2.54 mm
• Package Code: PDIP0032GA-A

Ordering Information

The HM628512BI is available in multiple speed grades and package options. The ordering part number is constructed as follows:

• HM628512BI-70: 70 ns access time
• HM628512BI-85: 85 ns access time

Package options are indicated by a suffix (e.g., -L for SOP, -T for TSOP II, -P for DIP).

Conclusion

The Hitachi HM628512BI 4-Mbit SRAM offers an optimal balance of performance, power efficiency, and reliability for demanding applications. Its wide operating temperature range, battery backup capability, and multiple package options make it a versatile choice for designers across industries. Whether used in portable devices, industrial systems, or automotive electronics, the HM628512BI delivers consistent performance while minimizing power consumption.