CM8501/A
1.5A B
US
T
ERMINATOR
FUNCTIONAL DESCRIPTION
The CM8501/A is a switching regulator that is capable of
sinking and sourcing 1.5A of current without an external heat
sink. CM8501/A uses a standard surface mount PTSSOP
and PSOP package with bottom metal exposed and the heat
can be piped through the bottom of the device and onto the
PCB.
The CM8501/A integrates power MOSFETs that are capable
of source and sink 1.5A of current while maintaining excellent
voltage regulation. The output voltage can be regulated within
3% or less by using the external feedback. Separate voltage
supply inputs have been added to fit applications with various
power supplies for the databus and power buses.
INPUTS
The input voltage pins (VCCQ & VIN/2 of CM8501 or VCCQ of
CM8501A) determine the output voltages (VL). At CM8501,
when the VIN/2 pin is open, the output voltage is 50% of the
VCCQ input. If a specific voltage is forced at the VIN/2 pin, the
output voltage follows the voltage at the VIN/2 pin. At CM8501A,
the output voltage is always 50% of the VCCQ input.
VCCQ is suggested to connect to VCCQ of memory module for
better tracking with memory VCCQ.
OTHER SUPPLY VOLTAGES
Several inputs are provided for the supply voltages: PVDD and
VCCA
The PVDD provide the power supply to the power MOSFETs.
VCCA provide the voltage supply to the logic section and
internal error amplifiers of CM8501/A.
OUPUTS
The output voltage pins (VL) are tied to the databus, address,
or clock lines via an external inductor. Output voltage is
determined by the VCCQ or VIN/2 inputs for CM8501 and is
determined by the VCCQ only for CM8501A.
FEEDBACK
The VFB pin is an input that can be used for closed loop
compensation. This input is derived from the voltage output.
AGSEN pin is a contact node of internal resistor divider for
remote sense (CM8501).
2006/10/11
Rev. 1.3
Champion Microelectronic Corporation
Page 6
CHAMP [ CHAMPION MICROELECTRONIC CORP. ]
