APW8871 Datasheet, PDF (2/27 Pages) Anpec Electronics Coropration – DDR4 TOTAL POWER SOLUTION (VPP/VDDQ/VTT) SYNCHRONOUS DC/DC CONVERTER for NB/MB

APW8871
General Description (cont.)
Applications
The LDO is designed to provide a regulated voltage with •
bi-directional output current for DDR-SDRAM termination. _•
The device integrates two power transistors to source or
sink current up to 0.75A. It also incorporates current-limit
and thermal shutdown protection.
DDR3 and DDR4 Memory Power Supplies
NB/MB/Tablet
An internal resistor divider is used to provide a half volt-
age of VDDQ for VTTREF and VTT Voltage. The VTT out-
put voltage is only requiring 10µF of ceramic output ca-
pacitance for stability and fast transient response. The
S3 and S5 pins provide the sleep state for VTT (S3 state)
and suspend state (S4/S5 state) for device, when S5 and
S3 are both pulled low the device provides the soft-off for
VTT and VTTREF.
The APW8871 is available in 4mmx4mm 26-pin Thin QFN
package.
Simplified Application Circuit
V_IN
+4.5V~25V
VDDQ
L1
V_CC=5V
Q1
Q3
Q2
Q4
SMBUS Interface
SMC SMD
S3 S5
VPVCC =3 ~5 .5V
VTT
VDDQ/2
L2
VPP
VC C
C opyright © ANPEC Electronics C orp.
2
Rev. A.1 - Sep., 2015
www.anpec.com.tw