Conceptual
Complete DDR3/ DDR4 Memory Power Solution Converter
uP1740S
Features
General Description
Synchronous Buck Converter (VDDQ)
The uP1740S is a high performance synchronous buck
converter with 1.5Asource/sink LDO for memory system
power. It also provides a buffered low noise reference
VTTREF. The uP1740S has wide operation range from
4.5V to 26V for input voltage and 0.75V to 3.3V for memory
output voltage.
Wide Input Voltage Range from 4.5V to 26V
Fast Load Transient Response
Output Current up to 8A
RCOTTM Control Topology
The synchronous buck of the uP1740S adopts uPI
proprietary robust constant on-time (RCOTTM) PWM
scheme that features easy-to-use, low external component
count, fast transient response and quasi-constant
frequency operation over the operation range.
Soft-Off in S4/S5 States
Output or Adjustable from 0.75V to 3.3V
POK, OVP, UVP and Thermal Shutdown
LDO (VTT)
1.5A Source/Sink Capability
The 1.5A source/sink LDO for VTT has fast transient
response, requiring only two 10uF of ceramic output
capacitors. In addition, the LDO supply input is available
externally to significantly reduce the total power losses.
The uP1740S supports all the sleep state controls, in S3
state (suspend to RAM) VTT is disable and in S4/S5
(suspend to disk) VDDQ, VTT and VTTREF are soft off.
Requires Only Two 10uF Ceramic Output
Capacitors
Disable in S3 and Soft-Off in S4/S5
Thermal Shutdown
+
20mV Accuracy
Reference Voltage (VTTREF)
The uP1740S has complete functions including under
voltage protection, over current protection, over voltage
protection, power-up sequencing, power OK output, and
thermal shutdown. The uP1740S is available in WQFN4x4
- 32L package.
+
20mV Accuracy
+
Low Noise 10mA Output
RoHS Compliant and Halogen Free
Pin Configuration
Applications
Desktop PCs, Notebooks, and Workstations
Microprocessor and Chipset Supplies
DDR3/DDR3L/DDR4 Memory Power Supplies
SSTL-2 SSTL-18 and HSTL Bus Termination
PHASE
PGND
PGND
PGND
PGND
PGND
PGND
CS
NC
Exposed Pad II
(VIN)
Ordering Information
BOOT
VTTIN
VTT
Exposed Pad III
(PHASE)
Order Number
uP1740SQMI
Package Type
Remark
WQFN4x4 - 32L
VTTGND
VTTSNS
GND
Exposed Pad I
(VTTGND)
Note:
(1) Please check the sample/production availability with
uPI representatives.
VCC
(2) uPI products are compatible with the current IPC/
JEDEC J-STD-020 requirement. They are halogen-free,
RoHS compliant and 100% matte tin (Sn) plating that are
suitable for use in SnPb or Pb-free soldering processes.
uP1740S-DS-C3100, Dec. 2014
www.upi-semi.com
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