MAX5388EVMINIQU+ Maxim Integrated, MAX5388EVMINIQU+ Datasheet - Page 8

• Manufacturer Part Number: MAX5388EVMINIQU+
• Description: Digital Potentiometer Development Tools MAX5386/88/91/93 Eval Kit
• Manufacturer: Maxim Integrated
• Series: MAX5386, MAX5388r

Specifications of MAX5388EVMINIQU+

• Rohs: yes
• Product: Evaluation Systems
• Tool Is For Evaluation Of: MAX5388
• Resistance: 100 kOhms
• Operating Supply Voltage: 2.6 V to 5.25 V
• Interface Type: 3 Wire, Serial, USB

MAX5388 Evaluation System
The MAX5388 EV kit is an assembled and tested PCB
that features the MAX5388N 100kI dual digital poten-
tiometers. Both potentiometer A and B have an end-
to-end resistance of 100kI and each wiper can be
programmed independently among 256 tap positions.
The MAX5388 IC consists of one digital potentiometer in
a variable-resistor configuration and one digital potenti-
ometer in a voltage-divider configuration The EV kit uses
a MAX5388N IC in a 10 µMAX package on a proven two-
layer PCB design.
The EV kit provides connector J1 to interface with the
MAX5388 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 2.6V 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 2.6V to
5.5V to power the MAX5388 VDD input.
The VPOWER rail is typically supplied as 3.3V or 5V by
the MINIQUSB+ interface board circuitry, or 2.6V using
LDO regulator U6. The VPOWER rail sets the MAX5388
VDD input to 5V, 3.3V, or 2.6V. See Table 3 for proper
jumper configurations for setting the MAX5388 VDD input.
Table 3. VPOWER Rail (JU20)
*Default position.
Note: The MAX5388 VDD input has a minimum 2.6V requirement.
Table 4. Header J1 Pin Assignments
8
Detailed Description of Hardware
______________________________________________________________________________________
J1-2, J1-4, J1-6, J1-8
SHUNT POSITION
Not installed
J1-1
J1-3
J1-5
J1-7
1-3*
PIN
1-2
1-4
MAX5388 VDD Input Source
External source applied at EV kit VDD and
3.3V (MINIQUSB+ circuitry)
VPOWER
SIGNAL
5V (MINIQUSB+ circuitry)
SCLK
GND
DIN
CS
VPOWER RAIL
GND PCB pads
2.6V (LDO U6)
The MAX5388 features a clock and data-/chip-select
input pins for SPI-compatible communication to con-
trol the MAX5388 wiper position. The clock, data-, and
chip-select pins can be driven by the MINIQUSB+
interface circuit or the PCB header (J1), along with a
user-supplied external SPI-compatible controller. An
external SPI-compatible controller can be connected to
CS (J1-3), DIN (J1-5), SCLK (J1-7), and GND (J1-2) on
header J1 to communicate with the MAX5388 IC. When
using an external SPI-compatible controller, verify that
the MINIQUSB+ interface board has been disconnected
from the EV kit’s J2 and J3 headers. See Table 4 for
header J1 pin assignment.
The MAX5388 IC potentiometer A is internally configured
as a variable resistor. The EV kit allows potentiometer A
to be configured with ground reference by shorting LA
to ground. Table 5 lists jumper options for configuring
potentiometer A.
Verify that any power source connected to the WA or LA
pads are voltage and current limited to the maximum con-
ditions stated in the MAX5386/MAX5388 IC data sheet.
The EV kit provides an option to configure the MAX5388
potentiometer B as a potentiometer or voltage-divider,
(Potentiometer A)
Table 5. JU16 Jumper Function
Potentiometer, Voltage-Divider or Variable Resistor,
SHUNT POSITION
Not installed
Installed*
with Ground Reference (Potentiometer B)
External source applied at EV kit VDD and
SPI Clock and Data-/Chip-Select Inputs
Potentiometer, Variable Resistor with
Ground Reference (Potentiometer A)
Connected
connected
LA PAD
to GND
MAX5388 VDD INPUT
Not
GND PCB pads
3.3V
2.6V
5V
Potentiometer without
GND reference
Potentiometer with
GND reference
MAX5388 FUNCTION