Texas Instruments TLC5940 EVM, Руководство пользователя

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1.4 Jumper Descriptions
1.5 Data Input Modes
Introduction
1.3.3 J3 – Interface Connector
This connector is used to connect the TLC5940 EVM to the TUSB3210 interface board. The signals are
the same as on connector J1.
Table 4. J3 – Power Connector
Pin Direction
Pin Symbol Signal Name Function
Number (at board)
19 /22V_EN 22V Enable In This is an active low enable signal that turns on the 22V
power supply that is used to program the internal EEPROM
on the TLC5940 ICs.
20 VRPG_IN VPRG Data In This signal is buffered and combined with the /22V_EN signal
to set the VPRG voltage on the TLC5940 ICs.
21 XDOWN Error signal Out Error flag (LOD and TEF) output. Note: XDOWN of all three
devices is tied together.
22 DCPRG DC PRG Mode In Selects either the internal register or the internal EEPROM
when in DOT correction mode
23 GSCLK GS PWM Clock In Grayscale clock signal for 12-bit PWM dimming
24 BLANK Output enable In Output enable for all channels. Outputs are disabled when
BLANK is high.
25 XLAT Data latch In Rising edge latches data from shift register into the device
26 SCLK Serial data clock In Serial data input clock
27 SOUT_B Serial data output blue Out Serial data output for the blue LED IC. This is also the serial
data output in cascade mode
28 SIN_BLUE Serial data input blue In Serial data input for the blue LED IC
29 SOUT_G Serial data output green Out Serial data output for the green LED IC
30 SIN_GREEN Serial data input blue In Serial data input for the blue LED IC
31 SOUT_R Serial data output red Out Serial data output for the red LED IC
32 SIN_RED Serial data input red In Serial data input for the red LED IC. This is also the serial
data input when all three TLC5940 ICs are connected in
cascade mode (serially).
43,44 3.3V 3.3V Bias In This pin is the 3.3V bus from the TUSB3210 interface board.
It is not connected to the V_CC pins on the PWB. It can be
connected to V_CC on the PWB by inserting a 0-
Ω
resistor in
R18.
47, 48, GND Ground Power Signal ground
49, 50
1.4.1 JP1, JP2, JP3 – LED Test Current
These jumpers provide an easy place to measure the current flowing through the D0 red, green, and blue
LEDs. To measure the current, through an LED, remove the jumper and connect a current meter across
the jumper pins. Note that no current can flow through the LEDs if the jumpers are removed and a current
meter is not installed.
The TLC5940EVM-106 can be configured to accept data in two different modes: serially or in parallel. The
default configuration is serial mode. The EVM can be reconfigured for parallel data input by modifying
resistors R2, R3, R4, R6, R7, and R8 according to Table 5.
SLVU139 – September 2005 TLC5940 EVM 5