MAX6956EVKIT+ Maxim Integrated, MAX6956EVKIT+ Datasheet - Page 10

• Manufacturer Part Number: MAX6956EVKIT+
• Description: LED Lighting Development Tools Evaluation Kit for the MAX6956
• Manufacturer: Maxim Integrated
• Series: MAX6956r

Specifications of MAX6956EVKIT+

• Product: Evaluation Kits

MAX6956 Evaluation Kit
The MAX6956 EV kit is a fully assembled and tested
surface-mount PCB that contains a MAX6956 IC. The
MAX6956 is a 28-port LED driver and I/O expander.
The microcontroller circuitry (U2–U6) is equivalent to
Maxim’s MAXQ2000-based MINIQUSB board.
To use the MAX6956 EV kit with a user-supplied I
interface, first cut the JU5 and JU6 default traces, dis-
connecting SDA and SCL from the on-board microcon-
troller. If the user-supplied I
SCL/SDA pullup resistors, disable on-board pullup
resistors R7 and R8 by cutting the JU12 and JU13
default traces. Next, apply your own 2.5V to 5.5V power
supply between the EXT V+ and GND pads. Lastly,
connect your SCL and SDA signals to the correspond-
ing SDA and SCL test points on header H4 on the
MAX6956 EV kit board.
As shipped from the factory, the V+ supply voltage is
connected to the on-board 3.3V regulator by jumper JU2.
Configuring the EV kit to accept user-supplied power
between 2.5V and 5.5V requires cutting traces and
mounting additional components, as listed below. The
Absolute Maximum Rating of the MAXQ2000
10
Detailed Description of Hardware
______________________________________________________________________________________
User-Supplied I
Operation with External
2
2.5V to 5.5V Supply
C bus provides its own
2
C Interface
2
C
microcontroller is 3.6V. Warning: If SCL or SDA ever
exceed 3.6V, the microcontroller will be damaged.
To protect the MAXQ2000 against high voltage, a level-
translation circuit can be mounted on the board.
1) Obtain the following parts (Maxim does not supply
2) Cut the PCB trace that shorts across JU5 and JU6.
3) Mount components Q1, Q2, R12, and R14.
4) Connect external power supply between the EXT V+
5) Move JU2 shunt to 2-3 position.
To restore the EV kit, remove Q1 and Q2. Then install
shunts at JU5 and JU6. If Q1 and Q2 are not removed,
the 2N7002’s body diode will be forward-biased, which
may prevent the SCL and SDA signals from meeting min-
imum logic-high threshold V
DESIGNATION QTY
these components):
oval pad and the GND oval pad.
R12, R14
Q1, Q2
2
2
2N7002 (SOT23)
Central Semiconductor 2N7002FC
Diodes, Inc. 2N7002-7-F
Fairchild 2N7002_NL
Vishay/General Semiconductor
2N7002-E3
10kΩ ±5% resistors (0603)
IH
(min).
DESCRIPTION