Termination Regulator for DDR-SDRAMs - BD3539NUX | ROHM Semiconductor - ROHM Co., Ltd.
Termination Regulator for DDR-SDRAMs - BD3539NUX
BD3539NUX is a termination regulator that complies with JEDEC requirements for DDR1-SDRAM, DDR2-SDRAM, and DDR3-SDRAM. This linear power supply uses a built-in N-channel MOSFET and high-speed OP-AMPS specially designed to provide excellent transient response. It has a sink/source current capability of up to 1A and has a power supply bias requirement of 3.3 V (for DDR2 and DDR3) and 5.0 V (for DDR1, DDR2, and DDR3) for driving the N-channel MOSFET. By employing an independent reference voltage input (VDDQ) and a feedback pin (VTTS), this termination regulator provides excellent output voltage accuracy and load regulation as required by JEDEC standards. Additionally, BD3539 has a reference power supply output (VREF)for DDR-SDRAM or for memory controllers. Unlike the VTT output that goes to "Hi-Z" state, the VREF output is kept unchanged when EN input is changed to "Low", making this IC suitable for DDR-SDRAM under "Self Refresh" state.
Vout (Typ.) [V]
0.75 to 1.25
Under Voltage Lock Out
Operating Temperature (Min.)[°C]
Operating Temperature (Max.)[°C]
Features:· Incorporates a Push-Pull Power Supply for Termination (VTT)
· Incorporates a Reference Voltage Circuit (VREF)
· Incorporates an Enabler
· Incorporates an Under Voltage Lockout (UVLO)
· Incorporates a Thermal Shutdown Protector (TSD)
· Compatible with Dual Channel (DDR1, DDR2, DDR3)
· Usable Ceramic Capacitor at Output