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2009.10 - Rev.
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Hi-performance Regulator IC Series for PCs
Termination Regulators
for DDR-SDRAMs
BD3539FVM,BD3539NUX
Description
BD3539FVM/NUX is a termination regulator compatible with JEDEC DDR1-SDRAM, DDR2-SDRAM, DDR3-SDRAM which
functions as a linear power supply incorporating an N-channel MOSFET and provides a sink/source current capability up to
1A respectively. A built-in high-speed OP-AMP specially designed offers an excellent transient response. Requires 3.3
volts (DDR2, DDR3) or 5.0 volts (DDR1, DDR2, DDR3) as a bias power supply to drive the N-channel MOSFET. Has an
independent reference voltage input pin (VDDQ) and an independent feedback pin (VTTS) to maintain the accuracy in
voltage required by JEDEC, and offers an excellent output voltage accuracy and load regulation. Also has a reference
power supply output pin (VREF) for DDR-SDRAM or a memory controller. When EN pin turns to “Low”, VTT output
becomes “Hi-Z” while VREF output is kept unchanged, compatible with “Self Refresh” state of DDR-SDRAM.
Features
1) Incorporates a push-pull power supply for termination (VTT)
2) Incorporates a reference voltage circuit (VREF)
3) Incorporates an enabler
4) Incorporates an under voltage lockout (UVLO)
5) Employs MSOP8 package : 2.9×4.0×0.9(mm) : BD3539FVM
6) Employs VSON008X2030 package : 2.0×3.0×0.6(mm) : BD3539NUX
7) Incorporates a thermal shutdown protector (TSD)
8) Operates with input voltage from 2.7 to 5.5 volts
9) Compatible with Dual Channel (DDR1, DDR2, DDR3)
10) Usable ceramic capacitor at output
Use
Power supply for DDR1- SDRAM (VCC=5V only)
Power supply for DDR2-SDRAM (VCC=3.3V or 5V)
Power supply for DDR3-SDRAM (VCC=3.3V or 5V)
●ABSOLUTE MAXIMUM RATINGS
Parameter Symbol
Limit
Unit
BD3539FVM BD3539NUX
Input Voltage VCC 7
*1*2
V
Enable Input Voltage VEN 7
*1*2
V
Termination Input Voltage VTT_IN 7
*1*2
V
VDDQ Reference Voltage VDDQ 7
*1*2
V
Output Current ITT 1 A
Power Dissipation1 Pd1 387.4
*3
242.0
*4
mW
Power Dissipation2 Pd2 587.4
*4
515.0
*5
mW
Power Dissipation3 Pd3 - 877.2
*6
mW
Operating Temperature Range Topr -30～+100 ℃
Storage Temperature Range Tstg -55～+150 ℃
Maximum Junction Temperature Tjmax +150 ℃
*1 Should not exceed Pd.
*2 Instantaneous surge voltage, back electromotive force and voltage under less than 10% duty cycle.
*3 With Ta≧25℃ (With no heat sink) θja=322.6℃/W
*4 With Ta≧25℃ when mounting a 70mm×70mm×1.6mm glass-epoxy substrate, with no heat sinkθja=212.8℃/W
*5 With Ta≧25℃ (With no heat sink) θja=516.5℃/W
*6 With Ta≧25℃ when mounting a 70mm×70mm×1.6mm glass-epoxy substrate 1-layer board, θja=242.7℃/W
*7 With Ta≧25℃ when mounting a 70mm×70mm×1.6mm glass-epoxy substrate 4-layer board
(copper foil density: 5505mm
2
(copper foil area in each layer) ), θja=142.5℃/W
No.09030EAT24
