MAX6946EVKIT Maxim Integrated, MAX6946EVKIT Datasheet - Page 3

• Manufacturer Part Number: MAX6946EVKIT
• Description: LED Lighting Development Tools 10-Port Constant-Current LED Driver and I/O Expander with PWM Intensity Control
• Manufacturer: Maxim Integrated
• Series: MAX6946, MAX6947r

Specifications of MAX6946EVKIT

• Product: Demonstration Boards

The MAX6946 EV system (MAX6946EVCMAXQU) is a
complete 10-port, constant-current LED driver and I/O
expander system, consisting of a MAX6946 EV kit and
the Maxim interface board (CMAXQUSB).
The CMAXQUSB is a Maxim interface board that pro-
vides an I
Maxim devices. Maxim reserves the right to change the
implementation of this module at any time with no
advance notice.
The MAX6946 EV kit board provides a proven layout for
evaluating the MAX6946 constant-current LED dri-
ver/10-port I/O expander IC and can be obtained sepa-
rately without the CMAXQUSB. The 10 I/O ports can be
configured as logic inputs, open-drain logic outputs,
constant-current sink outputs, or any combination of the
above. The EV kit includes three RGB LEDs (D1, D2,
and D3) and one white LED (D4). These LEDs can be
enabled and the current through each LED can be con-
trolled using the MAX6946 EV kit software (see the
Detailed Description of Software section).
The MAX6946 EV kit includes PCB pads (R2–R11) on the
bottom side of the PCB that can be used to add pullup
resistors at each of the MAX6946’s P0–P9 ports to oper-
ate the EV kit in logic input/output mode.
The MAX6946 EV kit requires a 2.25V to 3.6V power
supply connected to the VDD and GND PC pads for
normal operation. The EV kit can also use the
CMAXQUSB interface board’s 3.3V power source by
installing a shunt across jumper JU1 on the MAX6946
EV kit and configuring the CMAXQUSB interface board
VDD. Set jumper JU1 in the CMAXQUSB to 3.3V. See
Table 1 for EV kit jumper JU1 configuration. Note:
Insure that all of the data sheet absolute maximum
specifications are not violated when operating the
MAX6946 EV kit.
The EV kit also requires a 5.5V to 7V voltage source
connected to the VLED and GND pads to power the
LEDs when operating the EV kit in input/current-sink
mode. Use voltages from 2.25V to 7V to provide a
pullup voltage during logic output/input operation.
MAX6946 Evaluation Kit/Evaluation System
2
C interface bus to demonstrate various
_______________________________________________________________________________________
Detailed Description of
MAX6946 EV System
MAX6946 EV Kit
Power Supplies
Hardware
CMAXQUSB
The EV kit features a pushbutton switch, SW1, that con-
nects the MAX6946 RST pin to ground. Push and hold
the pushbutton switch to connect the RST pin to
ground. Refer to the RST Input section in the MAX6946/
MAX6947 IC data sheet to use this RST feature.
The MAX6946 EV kit includes three RGB LEDs (D1, D2,
and D3) and one white LED (D4) connected to the 10 I/O
ports through shunts installed on header J2. The LEDs
are enabled by configuring the respective port on the
MAX6946 to constant-current static output, constant-cur-
rent PWM output, or low-logic output mode. For logic
operation at each port, remove the shunts on header J2,
install 10kΩ pullup resistors on PC pads R2–R11, and
configure the ports for logic outputs or inputs.
The MAX6946 EV kit features a 2 x 10 right-angle header
receptacle (J1) to interface with the CMAXQUSB inter-
face board. Pin J1-7 connects to the MAX6946 clock pin
(SCL) and pin J1-3 connects to the data pin (SDA) for
I
switches on the CMAXQUSB interface board to the ON
position to connect pullup resistors to the SCL and SDA
signal lines for proper I
The clock and data input pins can also be accessed at
the SCL and SDA EV kit PCB pads, respectively. An
external I
the SCL, SDA, and GND PCB pads to communicate
with the MAX6946 IC. If the external device does not
have pullup resistors on the clock and data lines, 2.4kΩ
(typ) pullup surface-mount resistors (0603 size) must
be installed on R12 and R13 PCB pads for proper I
communication. The GND PCB pad must also be con-
nected to the external I
Table 1. Voltage Source Selection
(Jumper JU1)
* Default configuration.
2
Not installed
C-compatibale communications. Slide both SW1 dip
POSITION
Installed*
SHUNT
2
C-compatible controller can be connected to
Power supplied from the CMAXQUSB.
Note: Verify that the CMAXQUSB JU1 voltage
is configured to 3.3V.
User-supplied power source required at the
EV kit VDD and GND pads.
I
2
2
2
C communication.
C controller.
C Clock and Data Inputs
EV KIT FUNCTION
RST Input
I/O Ports
2
C
3