Datasheet
Termination Regulators for DDR-SDRAMs
BD3538F BD3538HFN
General Description
Key Specifications
BD3538F/HFN is a termination regulator that complies
with JEDEC requirements for DDR-SDRAM. This
linear power supply uses a built-in N-channel MOSFET
and high-speed OP-AMPS specially designed to
Termination Input Voltage Range:
VCC Input Voltage Range:
VDDQ Reference Voltage Range:
Output Voltage:
1.0V to 5.5V
2.7V to 5.5V
1.0V to 2.75V
1/2 x VVDDQ V(Typ)
1.0A (Max)
provide excellent transient response. It has
a
Output Current:
sink/source current capability of up to 1A and has a
power supply bias requirements of 3.3V to 5.0V for
driving the N-channel MOSFET. By employing an
High side FET O-Resistance:
Low side FET ON-Resistance:
Standby Current:
0.4Ω(Typ)
0.4Ω(Typ)
0.5mA (Typ)
independent reference voltage input (VDDQ) and
a
Operating Temperature Range:
-40°C to +105°C
feedback pin (VTTS), this termination regulator
provides excellent output voltage accuracy and load
regulation as required by JEDEC standards.
Additionally, BD3538 has a reference power supply
Packages
W(Typ) x D(Typ) x H(Max)
output (VREF) for DDR-SDRAM or
a memory
controller. 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.
SOP8
Features
5.00mm x 6.20mm x 1.71mm
Incorporates a push-pull power supply for
termination (VTT)
Incorporates a reference voltage circuit (VREF)
Incorporates an enabler
Incorporates an undervoltage lockout (UVLO)
Incorporates a thermal shutdown protector (TSD)
Compatible with Dual Channel (DDR-II)
Applications
HSON8
2.90mm x 3.00mm x 0.60mm
Power supply for DDR I / II - SDRAM
Typical Application Circuit, Block Diagram
VTT_IN
VCC
VDDQ
VCC
VTT_IN
VDDQ
6
5
7
VCC
VCC
VCC
UVLO
SOFT
Reference
VTT
Block
TSD
VTT
8
EN
TSD
EN
UVLO
VCC
UVLO
UVLO
TSD
EN
UVLO
TSD
Thermal
3
Protection
Enable
VTTS
½ x
VDDQ
4
EN
EN
VREF
2
1
GND
○Product structure:Silicon monolithic integrated circuit ○This product has no designed protection against radioactive rays
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02.Nov.2015 Rev.001
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