Cypress CY7C1021CV33-10ZXCT 1Mb SRAM IC
The Cypress CY7C1021CV33-10ZXCT is a high-speed 1-megabit (1Mbit) static RAM (SRAM) organized as 64K words by 16 bits (64K x 16). It operates on a 3.3V power supply and features a 10 ns access time, making it suitable for cache memory, PLC memory expansion, and embedded systems. The device comes in a 44-pin TSOP II (Type II) package with lead-free finish (ZXCT suffix indicates Pb-free, TSOP-II, Tape & Reel).
Electrical Characteristics
Power supply (Vcc): 3.0V to 3.6V, typical 3.3V.
Standby current (Icc2): 2 mA max (CMOS level inputs).
Operating current (Icc): 110 mA max at 10 ns cycle.
Access time: 10 ns (address to data valid).
Output drive: 8 mA at 3.3V.
The device features automatic power-down when deselected (CE1 high or CE2 low, or BHE/BLE high).
Pinout and Functionality
Pins: A0–A15 (address inputs), I/O0–I/O15 (bidirectional data), CE1 (chip enable 1 active low), CE2 (chip enable 2 active high), BHE (byte high enable, controls upper byte), BLE (byte low enable), OE (output enable), WE (write enable), and Vcc/Vss. The SRAM supports individual byte read/write via BHE/BLE. The device is fully static — no clock or refresh required.
Package and Thermal Data
44-pin TSOP II (Type II) with 0.8mm lead pitch. Package dimensions: 18.41 mm x 10.16 mm x 1.0 mm (body). Operating temperature: 0°C to 70°C (commercial grade). Storage: -55°C to +125°C. The lead finish is 100% matte tin (Sn) per RoHS. Thermal resistance (junction-to-ambient): 60°C/W typical.
Timing Specifications
Read cycle: tAA = 10 ns, tOE = 5 ns (from OE low). Write cycle: tWC = 10 ns min, tPWE = 7 ns (pulse width). The device supports both OE controlled and WE controlled write operations. Output hold time: 3 ns after address change.
Applications in PLC Systems
This SRAM is commonly used as external memory expansion for PLC CPUs (e.g., legacy 16-bit controllers), storing ladder logic program steps, data registers, and retentive values. It can also be found in industrial network cards, HMI motherboards, and motion control boards. The 10 ns access time supports high-speed CPU buses up to 100 MHz.
Handling and Soldering
Moisture sensitivity level (MSL) 3, shelf life 168 hours after opening. Reflow soldering compatible (peak temperature 260°C, 10 sec max). ESD sensitivity class 2 (HBM 2 kV). The device is not radiation hardened; not for aerospace.
Ordering Information
Full part number: CY7C1021CV33-10ZXCT. 'ZXCT' = TSOP II, Pb-free, Tape & Reel (1000 units per reel). Alternatively, 'ZXC' for tray packing. Cross references: CY7C1021CV33-10ZC (older leaded version), or equivalent IDT71V416S10PH. The Cypress part is now part of Infineon portfolio.
Datasheet and Compliance
Manufacturer: Cypress (now Infineon). The device is JEDEC standard compliant. RoHS, REACH, and China RoHS compliant. No halogen or antimony. Manual: CY7C1021CV33 Data Sheet (Cypress Document No. 38-05041).
