APW8871 Datasheet, PDF (1/27 Pages) Anpec Electronics Coropration – DDR4 TOTAL POWER SOLUTION (VPP/VDDQ/VTT) SYNCHRONOUS DC/DC CONVERTER for NB/MB

APW8871
DDR4 TOTAL POWER SOLUTION (VPP/VDDQ/VTT)
SYNCHRONOUS DC/DC CONVERTER for NB/MB
Features
Provide 4 Independent Outputs for VPP, VDDQ,VTT LDO
and VTTREF LDO
VDDQ Converter
• High Input Voltages Range from 4.5V to 25V Input
Power
• Provide 1.2V (DDR4) or Adjustable Output Voltage
Max to 1.8V by SMBus Control
- +1% Accuracy over Temperature
• High Efficiency Performance up to90%scale & Low
Shutdown Current <1uA
• Integrated High_Side N-Channe l MOSFET 20mΩ
a nd Low_ Side N-Cha nne l MOSFET 10 m Ω @
VCC=5V
• Integrated Bootstrap Forward P-CH MOSFET
• Built in Internal Soft-Sta rt: 0.4 ms(typ.) and Soft-
Stop Functions for PWM Output
• Built In Automatic PFM/PWM Mode Selection
• Fixed 800kHz Switching Frequency
• S3 andS5 Pins Control The Device in S0, S3 or S4/
S5 State
• Built In PMAX Signal for Total Power Indicator
• Power Good Monitoring
• 60% Under-Voltage Protection (UVP)
• 125% Over-Voltage Protection (OVP)
• Built in Fixed Valley Current Limit Protection
• Built In Thermal Shutdown Function
VPP Converter
• Integrated High_Side P-Channel MOSFET 220mΩ
and Low_ Side N-Channe l MOSFET 2 00 mΩ @
VCC=5V
• Excellent Reference Voltage = 0.6V
- +1% Load/Line Regulations over all TC range
• Fixed 1MHz switching Frequency
• Built in Internal Soft-Sta rt: 0.2 ms(typ.) and Soft-
Stop Functions for PWM Output
• 60% Under-Voltage Protection (UVP)
• 125% Over-Voltage Protection (OVP)
• Built in Fixed Valley Current Limit Protection
• Built In Thermal Shutdown Function
+0.75A LDO Section (VTT)
• Support Only 10µF MLCC for Stability on VTT LDO
• VTT and VTTREF Track at Halfthe VDDQ by internal
divider
• Built In 0.7 5A Source/Sink Capability on VTT LDO
and 10mA Source/Sink Capability on VTTREF LDO
• Independent Current Limit Protection
• Thermal Shutdown Protection
• 4mmx4mm 26-pin package (TQFN-26)
• Halogen and LeadFree Available (RoHSCompliant)
General Description
The APW8871 integrates two synchronous buck PWM
controller and high/low side power MOSFETs to gener-
ate VPP and VDDQ, two sourcing and sinking LDO linear
regulator to generate VTT and VTTREF. It provides a com-
plete power supply for DDR4 memory system. It offers
the lowest total solution cost in system where space is at
a premium.
The APW8871 provides excellent transient response
and accurate DC voltage output in PFM Mode. In Pulse
Frequency Mode (PFM), the APW8871 provides very
high efficiency over light to heavy loads with loading-
modulated switching frequencies.
The APW8871 has maximum power indicator function
in order to prevent over load condition. The device also
has single enable for VPP and VDDQ with JEDEC
sequence implemented. Moreover, the APW8871
integrates SMBus controller to program VDDQ output
voltage, VDDQ DAC voltage adjustment, VDDQ voltage
slew rate setting, and VDDQ PWM converter frequency.
The APW8871 is equipped with accurate current-limit,
output under-voltage, output over-voltage and over-tem-
perature protections. A Power-On- Reset function moni-
tors the voltage on VCC prevents wrong operation during
power on.
ANP EC res erves the right to ma ke cha nges to imp rove relia bility or m anufac turab ility witho ut no tice, and
advise customers to obtain the latest version of relevant information to verify before placing orders.
C opyright © ANPEC Electronics C orp.
1
Rev. A.1 - Sep., 2015
www.anpec.com.tw