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APW8821
Notebook PWM Controller with Differential Voltage Feedback
Features
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Adjustable Output Voltage from +0.5V to +3.3V - 0.5V Reference Voltage - +0.6% Accuracy
General Description
The APW8821 is a single-phase, constant on-time, synchronous PWM controller, which drives N-channel MOSFETs. The APW8821 steps down high voltage to generate low-voltage chipset or RAM supplies in notebook computers. The APW8821 provides excellent transient response and accurate DC voltage output in either PFM or PWM Mode. In Pulse Frequency Mode (PFM), the APW8821 provides very high efficiency over light to heavy loads with loadingmodulated switching frequencies. In PWM Mode, the converter works nearly at constant frequency for low-noise requirements. APW8821 is built in remote sense function for applications that require remote sense.
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Operates from An Input Battery Voltage Range of +1.8V to +28V Remote Feedback Sense for Excellent Output Voltage REFIN Function for Over-clocking Purpose from 0.5V~2.5V range Power-On-Reset Monitoring on VCC Pin Excellent line and load transient responses PFM mode for increased light load efficiency 350kHz Constant PWM Switching Frequency Integrated MOSFET Drivers Integrated Bootstrap Forward P-CH MOSFET Adjustable Integrated Soft-Start and Soft-Stop Power Good Monitoring 70% Under-Voltage Protection 125% Over-Voltage Protection Adjustable Current-limit protection -Using Sense Low-Side MOSFET? ¦ s RDS(ON) Over-Temperature Protection TDFN-10 3x3 package Lead Free and Green Device Available (RoHS Compliant)
The APW8821 is equipped with accurate positive current limit, output under-voltage, and output over-voltage protections, perfect for NB applications. The PowerOn-Reset function monitors the voltage on VCC to prevent wrong operation during power-on. The APW8821 has a 1ms digital soft start and built-in an integrated output discharge device for soft stop. An internal integrated soft-start ramps up the output voltage with programmable slew rate to reduce the startup current. A soft-stop function actively discharges the output capacitors.
The APW8821 is available in 10pin TDFN 3x3 package respectively.
Applications
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Notebook Table PC Hand-Held Portable AIO PC
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. Rev. A.1 - Feb., 2012 1 www.anpec.com.tw
Free Datasheet http://www.datasheet4u.com/
APW8821
Simplified Application Circuit
VCC=5V RPOK POK REFIN VIN
UGATE
Q1 L VOUT
APW8821
VOUT RTN PHASE LGATE/ OCSET Q2
Ordering and Marking Information
APW8821 Assembly Meterial Handling Code . Temperature Range Package Code APW 8821 XXXXX
Package Code QB: TDFN3x3-10 . Temperature Range I : -40 to 85 oC Handling Code TR : Tape & Reel Assembly Meterial L : Lead Free Device G : Halogen and Lead Free Device
APW 8821 QB :
XXXXX - Date Code
Note: ANPEC lead-free products contain molding compounds/die attach materials and 100% matte tin plate termination finish; which are fully compliant with RoHS. ANPEC lead-free products meet or exceed the lead-free requirements of IPC/JEDEC J-STD-020D for MSL classification at lead-free peak reflow temperature. ANPEC defines “Green” to mean lead-free (RoHS compliant) and halogen free (Br or Cl does not exceed 900ppm by weight in homogeneous material and total of Br and Cl does not exceed 1500ppm by weight).
Pin Configuration
POK 1 REFIN 2 VOUT 3 RTN 4 FB 5 10 BOOT 9 UGATE 8 PHASE 7 VCC 6 LGATE/OCSET
TDFN3x3-10 Top View
= GND and Thermal Pad (connected to GND plane for better heat dissipation)
Copyright © ANPEC Electronics Corp. Rev. A.1 - Feb., 2011 2 www.anpec.com.tw
Free Datasheet http://www.datasheet4u.com/
APW8821
Absolute Maximum Ratings
Symbol VCC VBOOT-GND VBOOT
(Note 1)
Rating -0.3 ~ 7 -0.3 ~ 35 -0.3 ~ 7 -0.3 ~ VCC+0.3 -5 ~ VBOOT+0.3 -0.3 ~ VBOOT+0.3 -5 ~ VCC+0.3 -0.3 ~ VCC+0.3 -5 ~ 35 -1 ~ 30 150 -65 ~ 150 260 Unit V V V V V
Parameter VCC Supply Voltage (VCC to GND) BOOT Supply Voltage (BOOT to GND ) BOOT Supply Voltage (BOOT to PHASE) All Other Pins (FB, VOUT, POK, and REFIN to GND) UGATE Voltage (UGATE to PHASE) <20ns Pulse Width >20ns Pulse Width LGATE/OCSET Voltage (LGATE to GND) <20ns Pulse Width >20ns Pulse Width
V
VPHASE TJ TSTG TSDR
PHASE Voltage (PHASE to GND) <20ns Pulse Width >20ns Pulse Width Maximum Junction Temperature Storage Temperature Maximum Lead Soldering Temperature, 10 Seconds
V
o o o
C C C
Note1: Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Thermal Chara.