19-3635; Rev 0; 9/05
MAX6876 Evaluation Kit/Evaluation System
The MAX6876 evaluation system (EV system) consists
of a MAX6876 evaluation kit (EV kit) and a Maxim
CMOD232 command module. The MAX6876 EEPROMprogrammable quad power-supply tracker/sequencer
circuit monitors four system voltages and ensures proper power-up and power-down conditions for systems
requiring voltage tracking and/or sequencing.
The evaluation software (EV software) runs under
Windows® 98/2000/XP, providing a convenient user
interface to exercise the features of the MAX6876.
Order the complete EV system (MAX6876EVCMOD2)
for a comprehensive evaluation of the MAX6876 using a
PC. Order just the EV kit (MAX6876EVKIT) if the command module has already been purchased with a previous Maxim EV system, or if the EV kit is desired for
custom development in conjunction with other microcontroller-based systems.
This evaluation system data sheet assumes the reader
has a basic familiarity with the MAX6876 IC. Refer to
the MAX6876 IC data sheet for detailed specifications
and operating instructions.
Features
♦ Proven PC Board Layout
♦ Complete Evaluation System
♦ Convenient On-Board Test Points and
Connectors
♦ Fully Assembled and Tested
Ordering Information
TEMP RANGE
INTERFACE TYPE
MAX6876EVKIT
PART
0°C to +70°C
User supplied
MAX6876EVCMOD2
0°C to +70°C
Windows software,
RS-232 port
Note: The MAX6876 evaluation software is designed for use with
the complete EV system MAX6876EVCMOD2 (includes
CMOD232 module together with MAX6876EVKIT). If the
MAX6876 EV software will not be used, the MAX6876EVKIT
board can be purchased by itself without the CMOD232 module.
MAX6876 EV Kit
Component List
MAX6876 Stand-Alone EV Kit
The MAX6876 EV kit provides a proven PC board layout
to facilitate evaluation of the MAX6876. It must be interfaced to appropriate serial communication signals for
proper operation. Connect power, ground return, and
SCL/SDA interface signals to the breakout header pins
(see Figure 3). The load-switching FETs can control up
to four supply rails. Refer to the MAX6876 IC data sheet
for serial-data timing and electrical requirements.
MAX6876 EV System
The MAX6876 EV system software runs under Windows
98/2000/XP on an IBM-compatible PC, interfacing to the
EV system through the computer’s serial communications port. See the Quick Start section for setup and
operating instructions.
MAX6876 EV System
Component List
PART
QTY
DESCRIPTION
MAX6876EVKIT
1
MAX6876 evaluation kit
CMOD232
1
Command module
MAX6876 EV Kit
Software
1
User-interface software
Windows is a registered trademark of Microsoft Corp.
DESIGNATION
QTY
DESCRIPTION
C1–C4
4
10µF ceramic capacitors
KEMET C0805C106K9PACTU
C5–C8
0
Not installed
Nichicon UUD1H221MNL1GS
C9–C12
0
Not installed
KEMET C0805C106K9PACTU
C13–C16
4
1µF ceramic capacitors
KEMET C0805C105K8RACTU
CR1–CR6
6
1206 surface-mount LEDs
Fairchild Semiconductor
QTLP650D4TR
J1–J9, J11,
J12
11
Banana plug receptacles
Keystone Electronics 6095
J10
1
20-pin right-angle header
Samtec SSW-110-02-S-D-RA
JMP1, JMP2,
JMP6
3
3-pin headers, 0.1in centers
Samtec TSW-103-07-F-S
JMP3, JMP4,
JMP5, JMP7
4
2-pin headers, 0.1in centers
Samtec TSW-102-07-F-S
Q1–Q4
4
20V logic-level n-channel MOSFETs
International Rectifier IRLR3714Z
______________________________________________________________________________________
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
Evaluate: MAX6876
General Description
Evaluate: MAX6876
MAX6876 Evaluation Kit/Evaluation System
Component List (continued)
DESIGNATION
QTY
DESCRIPTION
R1
0
Surface-mount resistor (0805) (not
installed)
R2
0
Surface-mount resistor (0805) ) (not
installed)
R3–R6,
R12–R15, R17
9
R7–R11
5
DESIGNATION
QTY
DESCRIPTION
R16, R18
2
10kΩ surface-mount resistors (0805)
Panasonic ERJ-6GEYJ103V
SW1
1
Tactile switch, J-lead, E-switch
TL3301NF160QJ
100kΩ surface-mount resistors (0805)
Panasonic ERJ-6GEYJ104V
TP1–TP23
23
Triple-turret terminals
Keystone Electronics 1598-2
750Ω surface-mount resistors (0805)
Panasonic ERJ-6GEYJ751V
U1
1
MAX6876 power-supply sequencer
Maxim MAX6876ETX
Component Suppliers
SUPPLIER
PHONE
WEBSITE
E-Switch
763-504-3525
www.e-switch.com
Fairchild Semiconductor
800-341-0392
www.fairchildsemiconductor.com
International Rectifier
310-252-7105
www.irf.com
KEMET
864-963-6300
www.kemet.com
Keystone Electronics
718-956-8900
www.keyelco.com
Nichicon
858-824-1515
www.nichicon-us.com
Panasonic
800-344-2112
www.panasonic.com/industrial
Samtec
800-726-8329
www.samtec.com
Note: Indicate that you are using the MAX6876 when contacting these component suppliers.
Quick Start
Required Equipment
Before you begin, the following equipment is needed:
• Maxim MAX6876EVCMOD2 (contains MAX6876 EV
kit board and CMOD232 module)
Procedure
Do not turn on any power supplies until all connections are completed:
1) Set JMP1 to the 2-3 position for normal UVLO operation. See Table 1. If JMP1 is set to the 1-2 position,
install appropriate resistors at R1 and R2 to set the
desired UVLO voltage.
•
DC power supply, 9V DC at 200mA (included with
CMOD232 module)
•
Windows 98/2000/XP computer with an available
serial (COM) port
•
Standard 9-pin female-to-male straight-through serial cable
•
DC power supplies capable of providing 0 to 5V for
up to four channels of sequenced and/or tracked
power through the MAX6876 EV system. (Powersupply current requirements depend on user configuration and application.)
•
Test leads with 0.175in banana plugs to connect
the MAX6876 EV kit board to power supplies
2
_______________________________________________________________________________________
2) Set JMP2 to the 1-2 position to enable voltage
tracking/sequencing. Leaving JMP2 open allows
remote hardware control of the ENABLE pin
through the CMOD232 module. See Table 2.
3) Ensure JMP3 is not shorted for normal operation
(non-MARGIN functionality). See Table 3.
4) Ensure that shorting links at JMP4 and JMP5 are
installed to set the desired I2C address as shown in
Table 4. The MAX6876 EV kit I2C address must
correspond with the I2C address set in the evaluation software.
MAX6876 Evaluation Kit/Evaluation System
6) Place a shorting link at JMP7 if the MAX6876EVKIT
logic is to be powered from the CMOD232 module.
This connects the CMOD232 +5V supply to the
VLOGIC net of the MAX6876EVKIT. See Figure 3
and Table 6.
7) Carefully connect the EV kit and CMOD232 module
by aligning and fully mating the 20-pin header and
socket, P3 of the CMOD232 module and J10 of the
MAX6876EVKIT.
8) Connect a cable from the computer serial port to
the CMOD232 module. If using a 9-pin serial port,
use a straight-through female-to-male cable. If the
PC has a 25-pin serial connector, a standard 25-pin
to 9-pin adapter is required.
9) Install the evaluation software on your computer by
running the INSTALL.EXE program on the CD. The
program files are copied and icons are created in
the Windows Start menu.
10) Connect the DC power supply to the CMOD232
module at input jack P1.
11) Start the MAX6876 evaluation software by clicking
the program icon in the Start menu.
Detailed Description
of Software
Connecting to the MAX6876EVKIT
To connect to the MAX6876 EV kit, ensure that header
P3 of the CMOD232 module is plugged into J10 of the
MAX6876 EV kit and that both boards have power.
Note: Power can be supplied to the MAX6876 EV kit from
the CMOD232 module by installing a shorting link at
JMP7. This shorting link must be removed if the MAX6876
EV kit is to operate from another supply voltage.
Connect the CMOD232 module to an available serial
port on your PC using a standard straight-through
female-to-male 9-pin cable. Set jumpers JMP4 and
JMP5 on the MAX6876 EV kit to select the desired I2C
address, per Table 4.
Click the system menu on the MAX6876 EV software and
select Connect. A dialog box opens with pulldown
menus for COM port selection and I2C slave address.
Alternatively, clicking the Auto Detect checkbox causes
the EV software to search serial ports COM1–COM4 and
valid I2C addresses for a MAX6876 EV kit. Click the
Connect button for the EV software to establish I2C communication. If connection cannot be established,
recheck electrical connections, COM port assignment,
and the I2C slave address.
After the evaluation software locates the CMOD232
module and the MAX6876EVKIT board, the software
polls the configuration registers and updates the display every 500ms to reflect the current configuration.
Overview Tab
The evaluation software Overview tab shows a graphical representation of the four available power-supply
IN_/OUT_ pairs, with many mouse-sensitive features.
Figure 1 shows the appearance of the Overview tab for
a typical configuration.
Clicking and dragging any of the four power-supply
ramp waveforms allows OUT_ tracking assignment to
each of the four sequential ramps. The undervoltage/
overvoltage thresholds for each IN_/OUT_ pair can be
adjusted graphically or with the keyboard. To enter the
undervoltage or overvoltage thresholds using the keyboard, click the numeric threshold values on the left
side of the Overview tab and a dialog box will open.
This dialog box also allows selection of the threshold
increments, either 10mV or 20mV.
Underlined text on the Overview tab is used to represent configuration register values that can be adjusted
by selecting from a pulldown list. Other features, such
as Fault Behavior and Power-Down Mode, are configured by radio buttons. The graphical representation of
the IN_/OUT_ pairs changes to reflect Simultaneousor Reverse-Order Power-Down Mode.
For each IN_/OUT_ pair, a checkbox allows selection of
the 100Ω Pulldown resistance, and the adjustable
Overcurrent Threshold can also be enabled or disabled for each pair. Checking the Overcurrent
Threshold box for an IN_/OUT_ pair causes that channel to assert the OC output if the OUT_ voltage drops
below the selected overcurrent threshold percentage.
The Assert RESET checkboxes determine which OUT_
detectors assert the RESET output.
_______________________________________________________________________________________
3
Evaluate: MAX6876
5) Set JMP6 to provide either VCC or ABP voltage to
the VLOGIC net. The VLOGIC net must be connected
to ABP if the MAX6876 is to be powered from one
of the voltage-detector inputs (IN1–IN4), and the
CMOD232 module is not connected (or if JMP7 is
open). See Figure 3 and Table 5 for JMP6 settings.
Be sure to remove resistors R7–R10 if VLOGIC is to
be connected to ABP. Refer to the ABP section of
the MAX6876 IC data sheet.
Evaluate: MAX6876
MAX6876 Evaluation Kit/Evaluation System
Figure 1. Evaluation Software Overview Tab
Any changes made to the configuration parameters on
the Overview tab result in a corresponding change in
the MAX6876 configuration registers for the connected
MAX6876 EV kit. If configuration changes are made
and no MAX6876 EV kit is connected, a warning dialog
box will appear. Any changes made while disconnected are lost when connection is established.
Advanced Tab
The Advanced tab provides a detailed indication of the
current Register Values in a table format. Values can
be changed by selecting the appropriate field with the
mouse cursor. Values are shown for both the volatile
configuration registers and the corresponding nonvolatile EEPROM locations. Figure 2 shows the appear-
4
ance of the Advanced tab for a typical configuration.
Configuration register values can be stored in the configuration EEPROM by clicking on the Commit
Configuration button. Clicking the Locked checkbox
disables both register and EEPROM writes by setting
bit 2 of register 13h. To lock the EEPROM values, set
bit 2 of EEPROM location 33h.
Note: To unlock the EEPROM, first clear bit 2 of configuration register 13h, then clear bit 2 of EEPROM location 33h.
The Input Pin’s State box allows software remote control of the logic-level voltage applied by the CMOD232
module to the MARGIN, ENABLE, and MR pins of the
_______________________________________________________________________________________
MAX6876 Evaluation Kit/Evaluation System
Evaluates: MAX6876
Figure 2. Evaluation Software Advanced Tab
MAX6876, as long as the shorting links on JMP3 and
JMP2 are not installed. Physical jumper settings override any selections made in this box.
The MAX6876 can be configured to use its internal reference voltage or an external reference by selecting
the appropriate radio button in the Reference Voltage
box. If you choose to use an external reference, be sure
to physically connect a precision voltage source at test
point TP16 on the MAX6876 EV kit board. Selecting
external reference while none is connected causes the
part to repeatedly enter fault condition.
The I2C Enable box allows or prevents power sequencing/tracking to be enabled through the I2C interface. By
clicking the Allow enable with I2C checkbox, power
sequencing/tracking can be enabled or disabled by
clicking the Send Enable Command button. If the
Allow enable with I2C checkbox is not checked, the
MAX6876 ignores the I2C enable command bit. When
I2C enable is allowed by setting register 09h bit to 1,
the MAX6876 internal ENABLE is the result of an AND
condition between the I2C command bit (register 09h,
bit 0) and the logic ENABLE input at pin 11. Refer to the
logic ENABLE diagram in the MAX6876 data sheet.
The Fault Log box records the most recently detected
fault states. If the Fault Log box is full, a scrollbar
allows review of up to 1024 past fault messages. The
date and time data are from the PC clock.
_______________________________________________________________________________________
5
Evaluate: MAX6876
MAX6876 Evaluation Kit/Evaluation System
System Menu
The System menu is used to initiate the serial communication connection between the MAX6876 EV kit board
and the evaluation software. It can also be used to
assert a software reset of the MAX6876 by selecting the
Reboot Target option. Other functions available from
the System menu include Commit Configuration to
EEPROM and Lock Configuration, both of which are
functionally equivalent to their corresponding controls
on the Advanced tab.
Evaluation software configuration values can also be
saved to disk for future reference. Opening a saved
configuration file restores the previously saved configuration values to the registers of the connected
MAX6876 EV kit.
Colors Menu
The Colors menu selections and dialog boxes allow the
user to adjust evaluation software display colors to suit
individual preference. Be sure to choose contrasting
colors so that all display features remain visible.
Detailed Description
of Hardware
Connector J10 mates with the Maxim CMOD232 module, which enables communication with evaluation software running on a PC. As a convenience, the CMOD232
module provides 5V DC power to the VLOGIC net
through pin 1 of J10 and JMP7. This voltage can be
used to power U1 by placing a shorting link in position
2–3 of JMP6.
User-provided power supplies at J1–J4 are controlled
as the IN1–IN4 voltages, and are sequenced or tracked
as OUT1–OUT4 at J5–J8. These jacks accept a standard 0.175in tip-jack (banana plug) connector. Ground
connections can be established at J9, J11, and at test
points TP21 and TP23.
The MAX6876 EV kit is designed with 0.050in traces of
1oz copper for the main power paths. Each IN_/OUT_
pair safely handles up to 5A. Proceed with caution if
higher current operation is required.
Light-emitting diodes CR1–CR4 indicate the status of
the PG_ signals. A green LED indicates that power is
good. The PG_ signals can be monitored at test points
TP17–TP20. Likewise, CR5 indicates the status of the
REM signal.
Jumper Function Tables
The MAX6876 (U1) is mounted on an evaluation board
that includes all necessary support components for a
typical application circuit. The user power-supply input
(VCC, banana jack J12) is bypassed near U1 by 1µF
capacitor C13, and the internal supply voltage is
bypassed by 1µF capacitor C14.
The controlled IN_/OUT_ pairs are each bypassed with
10µF capacitors C1–C4. Additional surface-mount component leads are included for larger bypass caps if
desired, such as C5–C8. The OUT_ voltages are similarly provided with surface-mount lands for capacitors
C9–C12. Capacitors C5–C8 and C9–C12 are not
installed in the default configuration of the EV kit board,
and are not required in most applications.
Tables 1 through 5 describe the EV kit configuration
jumper functions. For a detailed understanding of the
jumpers, see Figure 3, the MAX6876 EV kit schematic.
Table 1. Jumper JMP1, TRKEN
Table 3. Jumper JMP3, MARGIN
JMP1 SHUNT
POSITION
6
FUNCTION
1-2
Adjust undervoltage-lockout threshold
using resistor-dividers R1 and R2
2-3
Normal operation; UVLO threshold is
1.285V
Table 2. Jumper JMP2, ENABLE
JMP2 SHUNT
POSITION
FUNCTION
1-2
Voltage tracking/sequencing enabled
2-3
Voltage tracking/sequencing disabled
Open
Evaluation software control of ENABLE
through CMOD232 module
JMP3 SHUNT
POSITION
1-2
Open
FUNCTION
MARGIN function enabled
Normal operation; MARGIN function
disabled, or under evaluation software
control through CMOD232 module
_______________________________________________________________________________________
MAX6876 Evaluation Kit/Evaluation System
Evaluates: MAX6876
Table 4. Jumpers JMP4 and JMP5, I2C Slave Address Selection
MAX6876 I2C ADDRESS
JMP4 SHUNT
POSITION
JMP5 SHUNT
POSITION
A1
A0
(BIT 3)
(BIT 2)
BINARY
HEXADECIMAL
1-2
1-2
0
0
101000xx
A0h
1-2
Open
0
1
101001xx
A4h
Open
1-2
1
0
101010xx
A8h
Open
Open
1
1
101011xx
ACh
Table 5. Jumper JMP6
JMP6 SHUNT
POSITION
FUNCTION
1-2
VLOGIC supplied from ABP pin of MAX6876
2-3
VLOGIC connected to VCC net (J12)
Open
CAUTIONARY NOTES
Resistors R7–R10 must be removed to prevent
loading ABP pin of MAX6876
—
—
VLOGIC supplied from pin 1 of J10 or TP22
Table 6. Jumper JMP7, CMOD232 Power Connection
JMP7 SHUNT
POSITION
FUNCTION
1-2
VLOGIC receives power from CMOD232 module
through pin 1 of J10
Open
No connection between CMOD232 module and
VLOGIC
CAUTIONARY NOTES
If shunt at JMP7 is installed, do not connect external
voltage to TP22
—
_______________________________________________________________________________________
7
1598
1598
1598
6095
6095
6095
6095
Figure 3. MAX6876 EV Kit Schematic
_______________________________________________________________________________________
SIP3
JMP6
3
2
1
TP15
1598
TP14
1598
TP13
1598
TP12
1598
TP11
1598
TP10
TP22
TP9
J12
J9
J4
J3
VCC
VCC
ABP
RESET
FAULT
OC
HOLD
R3
100Ω
SYNCH
R2
OPEN
R1
OPEN
UVLO
IN4
IN3
IN2
C16
1µF
R4
100Ω
VLOGIC
C5
OPEN
JMP1
SIP3
VLOGIC
R5
100Ω
VLOGIC
C13
1µF
VCC
C1
10µF
REM
2
C2
10µF
R6
100Ω
REM
1
C14
1µF
ABP
C6
OPEN
R11
750Ω
TRKEN
CR1
LED1206
3
ABP
C7
OPEN
REM
C3
10µF
VLOGIC
C8
OPEN
3
4
TACT
SW1
C4
10µF
1
2
FAULT
REM
OC
HOLD
SYNCH
TRKEN
ABP
GND
VCC
JMP2
SIP3
ABP
9
8
7
6
5
4
3
2
1
Q1
IRLR3714
1
GATE1
35
6095
36
IN1
J2
TP1
1598
TP5
1598
2
3
1
2
TP2
1598
Q2
IRLR3714
U1
VLOGIC
SIP2
JMP3
2
MAX6876ETX
IN2
N.C.
IN1
34
11
GATE2
32
14
TP6
1598
JMP7
SIP2
1
TP3
1598
GATE3
29
J1 J2
6095
OUT1
MARGIN
ENABLE
RESET
10
GATE1
ENABLE
12
MARGIN
GATE2
MR
MR
33
13
31
OUT2
SDA
15
2
1
28
IN4
4
3
PG1
PG2
PG3
PG4
N.C.
REFIN
OUT4
6
5
TP4
1598
8
7
10
9
11
12
14
13
PG1
19
16
15
ABP
PG2
20
VLOGIC
PG3
21
R13
100kΩ
GATE4
Q4
IRLR3714
PG4
R12
100kΩ
TP7
1598
22
23
24
25
26
27
Q3
IRLR3714
GATE4
OUT3
A1
30
IN3
SCL
16
GATE3
A0
17
8
18
18
17
SDA
SCL
R14
100kΩ
TP8
1598
20
19
J10
GPIO_K3
GPIO_K2
GPIO_K1
A0
A1
R15
100kΩ
2
1
2
1
R18 10kΩ
ENABLE
MARGIN
MR
C11
OPEN
CR4
LED1206
R9
750Ω
VLOGIC
VREFIN
CR3
LED1206
R8
750Ω
C10
OPEN
R17 100kΩ
R16 10kΩ
SDA
SCL
SIP2
JMP4
SIP2
JMP5
CR2
LED1206
R7
750Ω
C15
1µF
C9
OPEN
J8
J7
J6
1598
TP20
1598
TP19
1598
TP18
TP17
1598
1598
TP23
TP21
6095
JI1
TP16
1598
6095
6095
6095
J2 J5
6095
1598
CR5
LED1206
R10
750Ω
C12
OPEN
OUT4
OUT3
OUT2
OUT1
Evaluate: MAX6876
MAX6876 Evaluation Kit/Evaluation System
MAX6876 Evaluation Kit/Evaluation System
Evaluates: MAX6876
Figure 4. MAX6876 EV Kit Component Placement Guide—Component Side
_______________________________________________________________________________________
9
Evaluate: MAX6876
MAX6876 Evaluation Kit/Evaluation System
Figure 5. MAX6876 EV Kit PC Board Layout—Top Layer
10
______________________________________________________________________________________
MAX6876 Evaluation Kit/Evaluation System
Evaluates: MAX6876
Figure 6. MAX6876 EV Kit PC Board Layout—Bottom Layer
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 11
© 2005 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products, Inc.