RT9256 Datasheet, PDF (1/18 Pages) Richtek Technology Corporation – Actively Alternative Mode Two-Phase / Dual Switching PWM Controller

Preliminary
RT9256
Actively Alternative Mode Two-Phase / Dual Switching
PWM Controller
General Description
The RT9256 is an analogous current mode design and is
specifically promoted for high power density consideration
platform with MLCC capacitor attached, such as high-end
add-on graphic card core power and DDR SDRAM core
power, etc. A highlight for RT9256 is the RichTek’ s new
innovation of actively alternative mode operation two-phase
power conversion or dual PWM controller operation. Based
on above innovation architecture, the RT9256 provides more
flexibility and higher performance to customer application.
The part is implemented specially for multiple power
sourcing with power budget limitation. The part comes to
small footprint package VQFN-32L 5x5.
Ordering Information
RT9256
Package Type
QV : VQFN-32L 5x5 (V-Type)
Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer-
cial Standard)
Note :
Richtek Pb-free and Green products are :
`RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
`Suitable for use in SnPb or Pb-free soldering processes.
`100% matte tin (Sn) plating.
Features
z Analogous Current Mode Design
z Innovative Design for Actively Alternative Mode
Operation :
`Two-Phase Power Conversion
`Dual PWM Controllers
z 2.5V to 12V Switching Source Power
z 0.8V to 3.3V Output Voltage Regulation
z Multiple Power Sourcing for Power Budget Limitation
z Adjustable V_IN Feed-Forward Ramp Slope
z Adjustable Operation Frequency
z Precision Core Voltage Regulation
z Precision DCR Current Sensing (with High Quality
Capacitor, X7R)
z ±1% V_REF Accuracy
z Input Voltage : 12V or 5V Bias
z Enable and PGOOD Function for Sequencing-
Concerned Power
z Over Current Protection
z Over Voltage Protection
z External Soft Start Setting
z Operation Frequency Up to 1.0MHz Per Channel
z 32-Lead VQFN Package
z RoHS Compliant and 100% Lead (Pb)-Free
Pin Configurations
(TOP VIEW)
Applications
z Add-on graphic core power card
z DDR SDRAM core power
z Gaming Console
z High power density consideration platform
z Desktop/motherboard high power devices
z Power sequencing-concerned power application
32 31 30 29 28 27 26 25
CSN1 1
CSP1 2
COMP1 3
FB1 4
FB2 5
24 PHASE1
23 _PGND
22 LGATE1
21 _PVCC
20 PVCC
COMP2 ⁶
19 LGATE2
CSP2 7
33
18 PGND
CSN2 8
17 PHASE2
9 10 11 12 13 14 15 16
DS9256-07 August 2007
VQFN-32L 5x5
www.richtek.com
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