APL5331 Datasheet, PDF (1/20 Pages) Anpec Electronics Coropration – 3A Bus Termination Regulator

APL5331
3A Bus Termination Regulator
Features
General Description (Cont.)
• Provide Bi-direction Current
 - Sourcing or Sinking Current up to 3A
• 1.25V/0.9V Output for DDR I/II Applications
• Fast Transient Response
• High Output Accuracy
- ±20mV over Load, VOUT Offset and
Temperature
• Adjustable Output Voltage by External Resistors
• Current-Limit Protection
• On-Chip Thermal Shutdown
• Shutdown for Standby or Suspend Mode
• Simple SOP-8, SOP-8-P with thermal pad,
TO-252- 5 and TO-263-5 Packages
On-chip thermal shutdown provides protection against
any combination of overload that would create ex-
cessive junction temperature. The output voltage of
APL5331 track the voltage at VREF pin. A resistor
divider connected to VIN, GND and VREF pins is
used to provide a half voltage of VIN to VREF pin. In
addition, an external ceramic capacitor and an open-
drain transistor connected to VREF pin provides soft-
start and shutdown control respectively. Pulling and
holding the VREF to GND shuts off the output. The
output of APL5331 will be high impedance after be-
ing shut down by VREF or thermal shutdown function.
Pin Configuration
Applications
• DDR I/II SDRAM Termination
• SSTL-2/3 Termination Voltage
• Applications Requiring the Regulator with
Bi-direction 3A Current Capability
General Description
The APL5331 linear regulator is designed to provide
a regulated voltage with bi-directional output current
for DDR-SDRAM termination. The APL5331 integrates
two power transistors to source or sink current up to
3A. It also incorporate current-limit, thermal shut-
down and shutdown control functions into a single
chip. Current-limit circuit limits the short-circuit
current.
VIN 1
GND 2
VREF 3
VOUT 4
8 ^VCNTL
7 VCNTL
TAB is VCNTL
6 VCNTL
5 VCNTL
VOUT
VREF
VCNTL
GND
VIN
SOP-8 (Top View)
TO-252-5 (Top View)
VIN 1
GND 2
VREF 3
VOUT ₄
8 NC
7 NC
TAB is VCNTL
6 VCNTL
5 NC
5
VOUT
4
VREF
3
VCNTL
2
GND
1
VIN
SOP-8-P (Top View) TO-263-5 (Top View)
NC = No internal connection
= Thermal Pad
(connected to GND plane for better heat
dissipation)
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise
customers to obtain the latest version of relevant information to verify before placing orders.
Copyright  ANPEC Electronics Corp.
1
Rev. A.8 - Oct., 2003
www.anpec.com.tw