MAX5393EVMINIQU+ Maxim Integrated, MAX5393EVMINIQU+ Datasheet - Page 8

• Manufacturer Part Number: MAX5393EVMINIQU+
• Description: Digital Potentiometer Development Tools MAX5393 Eval Kit
• Manufacturer: Maxim Integrated
• Series: MAX5391, MAX5393r

Specifications of MAX5393EVMINIQU+

• Rohs: yes
• Product: Evaluation Systems
• Tool Is For Evaluation Of: MAX5393
• Resistance: 50 kOhms
• Operating Supply Voltage: 1.7 V to 5.25 V
• Interface Type: 3 Wire, Serial, USB

MAX5393 Evaluation System
Problem:_Software_reports_it_cannot_find_the_interface_
circuit:
• Is the USB cable connected to the MINIQUSB+ board?
• Has Windows plug-and-play detected the board?
• If using an off-board SPI interface, is the power ground
The MAX5393 EV kit is an assembled and tested PCB
that features the MAX5393M 256-tap, 50kI, dual digital
potentiometer. Each wiper can be programmed inde-
pendently among 256 tap positions. The EV kit uses a
MAX5393M in a 16-pin TSSOP package on a proven
two-layer PCB design.
The EV kit provides connector J1 to interface with the
MAX5393 CS, DIN, SCLK, and GND signals directly to
a user-supplied 3-wire system. Connector J1 also pro-
vides a connection for the EV kit’s 1.7V to 5.5V VPOWER
power-supply input.
The EV kit is typically used with a MINIQUSB+ interface
board for communicating with a PC through the 3-wire
serial interface. Logic-level translators U7 and U8 pro-
vide proper SPI interface translation when using 1.7V to
5.5V to power the MAX5393 VDD input.
Table_3._VPOWER_Rail_(JU20)
Table_4._U5_LDO_Function_(JU1)
*Default position.
8_ _ _______________________________________________________________________________________
Detailed Description of Hardware
Not installed
POSITION
Bring up Control_Panel->System->Device_Manager,
and look at what device nodes are indicated for USB.
If there is an Unknown_ device_ node attached to
the USB, uninstall it—this forces plug-and-play to try
again.
connected to the EV kit ground (GND) at one of the
header J1 pin connections (J1-2, J1-4, J1-6, or J1-8)?
SHUNT_
JU20
SHUNT_POSITION
1-2
1-2
1-3
1-4
Not installed
Installed*
5V (MINIQUSB+ circuitry)
5V (MINIQUSB+ circuitry)
3.3V (MINIQUSB+ circuitry)
2.6V (LDO U6)
External source applied at VDD and GND
PCB pads
General Troubleshooting
VPOWER_SOURCE
U5_1.7V_OUTPUT_
Disabled
Enabled
The VPOWER rail is typically supplied as 3.3V or 5V by
the MINIQUSB+ interface board circuitry or 2.6V using
LDO regulator U6. LDO regulator U5 output is set to 1.7V
and is powered from the VPOWER rail. The VPOWER rail
and U5 are used to set the MAX5393 VDD input to 5V,
3.3V, 2.6V, or 1.7V.
Regulator U5 has an adjustable output that can be con-
figured to a different voltage by replacing resistor R1.
Use the following equation to set U5 output voltage:
where R1 is in ohms and VOUT is the desired U5 output
voltage.
Jumper JU20 selects the source for the MAX5393 EV
kit circuit VPOWER rail. See Table 3 for proper jumper
configuration for setting VPOWER rail.
Alternatively, the EV kit’s VDD PCB pad can be used to
supply an external 1.7V to 5.25V to the circuit’s VPOWER
rail, by removing the shunt at jumper JU20.
Jumper JU1 enables/disables U5 output. Install a shunt
across JU1 to enable U5 1.7V output. Remove the shunt
at JU1 to disable U5 output. See Table 4 for proper JU1
configuration.
Note:_LDO U6 output is disabled when the MINIQUSB+
board is not installed at headers J1 and J2.
Table_5._MAX5393_VDD_Power_Source_(JU19,_
JU1,_JU20)
*Default position.
X = Don’t care.
JU19
1-2*
1-2
2-3
SHUNT_POSITION
Installed*
installed
JU1
Not
X
R1 10
=
5
installed
EV Kit VDD Input Source
JU20
×
Not
1-2
1-3
1-4
X
X



VOUT
1.225
External source applied
−
at the EV kit VDD and
MAX5393_VDD_PIN
1



GND PCB pads
Not powered
1.7V
3.3V
2.6V
5V