CM8501C
1.5A B
US
T
ERMINATOR
GENERAL DESCRIPTION
The CM8501C is a low cost switching regulator designed to
provide a desired output voltage or termination voltage for
various applications by converting voltage supplies ranging
from 2.0V to 4.5V. The CM8501C can be implemented to
produce regulated output voltages in two different modes. In
the default mode, when the VIN/2 pin is open, the output
voltage is 50% of the VCCQ. The CM8501C can also be used
to produce various user-defined voltages by forcing a voltage
on the VIN/2 pin. In this case, the output voltage follows the
VIN/2 pin input voltage. The regulated output voltage of
CM8501C is internally set to be 50% of the applied VCCQ.
The switching regulator is capable of sourcing or sinking up to
1.5A of current while regulating an output V
TT
voltage to
within 3% or less.
The CM8501C provides low profile 8-pin PSOP package to
save system space.
FEATURES
Patent Filed #6,452,366
8-pin SOP packages
Source and sink up to 1.5A, no heat sink required
Peak Current to 3A
Integrated Power MOSFETs
Output voltage can be programmed by external resistors
Separate voltages for VCCQ and PVDD
V OUT of ±3% or less at 1.5A
Minimum external components
Shutdown for standby or suspend mode operation
Thermal shutdown protection
Soft start
APPLICATIONS
Mother Board
PCI/AGP Graphics
Game/ Play Station
Set Top Box
IPC
SCSI-III Bus terminator
Buck Converter
PIN CONFIGURATION
SOP-8 (S08)
Top View
1
2
3
4
VCCA
VCCQ
AGND
SD
PVDD
VL
PGND
VFB
8
7
6
5
2006/10/11
Rev. 1.2
Champion Microelectronic Corporation
Page 1
CM8501C
1.5A B
US
T
ERMINATOR
PIN DESCRIPTION
Pin No.
1
3
4
2
5
6
7
8
Symbol
VCCA
AGND
SD
VCCQ
VFB
PGND
VL
PVDD
Description
Voltage supply for internal circuits
Ground for internal reference voltage divider
Shutdown active high. CMOS input level
Voltage reference for external voltage divider
Feedback node for the V
TT
Ground for output power transistors
Output voltage/inductor connection (IDD1+IDD2,
Output RMS current)
Voltage supply for output power transistors
2.0
4.5
V
-1.5
+1.5
A
0.75 x
VCCA
2.5
VCCQ/2
VCCA
+ 0.3V
V
V
V
Operating Rating
Min.
Typ.
Max. Unit
2.0
4.5
V
ORDERING INFORMATION
Part Number
CM8501CIS
CM8501CGIS*
*Note: G : Suffix for Pb Free Product
Temperature Range
-40℃ to 85℃
-40℃ to 85℃
Package
8-Pin SOP (S08)
8-Pin SOP (S08)
BLOCK DIAGRAM
SD
4
AGND
3
VCCQ
2
VCCA
1
OSCILLATOR
RAMP GENERATOR
100K
100K
S
-
Q
R
ERROR AMP
+
RAMP AMP
COMPARATOR
Q
+
-
THERMO-
20PF
PROTECTION
5
VFB
6
PGND
7
VL
8
PVDD
2006/10/11
Rev. 1.2
Champion Microelectronic Corporation
Page 2
CM8501C
1.5A B
US
T
ERMINATOR
APPLICATION CIRCUITS
1.5A DDR BUS TERMINATOR DEMO BOARD CIRCUIT
VDD
VCC
C1
100uf/6.3V
NOTE:
JP3---->USEING INTERNAL REFERENCE
SOURCE(PIN 1, 2 SHORT)
JP3---->USEING EXTERNAL REFERENCE
SOURCE(PIN 2,3 SHORT)
R4
1k
2
1
J1
PWR/IN
TP1
BNC
1
D1
SK12
1
JP1
JUMPER
2
R1
100k
1
2
R2
1k
C3
470
1
5
4
3
2
C2
105
PGND
L1
3.3uH
D2
SK12
8
7
6
5
C8
10uf/6.3V
VDD
VL
FB
2
U2
CM-431
1
3
AGND
VCCQ
2
1
J2
VTT
1
2
J3
VREF-OUT
U1
C7
104
CM8501
C6
220uf/6.3V
VCC
SD
1
2
3
4
JP3
1
2
3
VCC
R6
5R1
1
C4
105
2
R5
0
1
JP2
JUMPER
2
VDD
C5
104
2
R3
100k
1
JP4
on/off sw
8-Pin Schematic
ABSOLUTE MAXIMUM RATINGS
Absolute maximum ratings are those values beyond which the
device could be permanently damaged.
PVDD/VCCA/VCCQ ......................................….......-0.3V to 4.5V
Voltage on Any Other Pin ………... GND – 0.3V to VCC + 0.3V
Output RMS Current, Source or Sink .....…………........…...1.5A
Junction Temperature ...…………………… …………150°C
Storage Temperature ……................……. -65°C to 125°C
Lead Temperature (Soldering, 5 sec)……………….. 300°C
Thermal Resistance(
θ
JA
)….. ……………….. .100°C/W
OPERATING CONDITIONS
Temperature Range ............................. -40°C to 85°C
P
VDD
Operating Range .........................2.0V to 4.5V
2006/10/11
Rev. 1.2
Champion Microelectronic Corporation
2
Page 3
CM8501C
1.5A B
US
T
ERMINATOR
(Unless otherwise stated, these specifications apply T
A
=25°C;
VCCA=+3.3V and PVDD=+3.3V)
maximum ratings are stress ratings only and functional device operation is not implied.
(Note 1)
CM8501C
Min.
1.12
1.22
1.32
1.09
1.19
1.28
1.139
1.238
1.337
Typ.
1.15
1.25
1.35
1.15
1.25
1.35
1.15
1.25
1.35
50
1.2
1.5
135
2.0
3
150
250
Max.
1.18
1.28
1.38
1.21
1.31
1.42
1.162
1.263
1.364
ELECTRICAL CHARACTERISTICS
Symbol
SWITCHING REGULATOR
Parameter
Test Conditions
Unit
IOUT = 0, VCCQ = 2.3V
VCCQ = 2.5V
Note 2
VL
Output Voltage, SSTL_2
IOUT =
±1.5A,
Note 2
Note 3
V
IN
/2
Z
IN
fsw
I
OUT(RMS)
I
OUT(PEAK)
OTS
MOSFETs
RDS
(ON)
SUPPLY
I
VCCA
I
PVDD
Quiescent Current
VFB = 1.4V
LC unconnected
VFB = 1.4V
LC unconnected
Drain to Source on-State Resistance
PVDD=5V
Internal Resistor Divider
V
IN
/2 Reference Pin Input Impedance
Switching Frequency
Minimum Output RMS Current
Maximum Output Peak Current
Over Temperature Shutdown
IOUT = 0
Note 2
Note 2
VCCQ = 2.7V
VCCQ = 2.3V
VCCQ = 2.5V
VCCQ = 2.7V
VCCQ = 2.3V
VCCQ = 2.5V
VCCQ = 2.7V
VCCQ = 0
V
V
V
V
V
V
V
V
V
KΩ
MHz
A
A
℃
mΩ
CM8501C
CM8501C
CM8501C
CM8501C
220
500
µA
µA
Note 1:
Limits are guaranteed by 100% testing, sampling, or correlation with worst case test conditions
Note 2:
VCCA, PVDD = 3.3V ±10%
Note 3:
Guaranteed by design, not 100% test
2006/10/11
Rev. 1.2
Champion Microelectronic Corporation
Page 4
CM8501C
1.5A B
US
T
ERMINATOR
FUNCTIONAL DESCRIPTION
The CM8501C is a switching regulator that is capable of
sinking and sourcing 1.5A of current without an external heat
sink.
The CM8501C 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) determine the output voltages
(VL). At CM8501C, 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 CM8501C.
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 and is determined by the VCCQ.
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.
PACKAGE DIMENSION
8-PIN SOP (S08)
PIN 1 ID
θ
θ
2006/10/11
Rev. 1.2
Champion Microelectronic Corporation
Page 5
电子工程世界
