NXP Semiconductors
UM11009
PCA9745B demonstration board OM13524
UM11009
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© NXP Semiconductors N.V. 2016. All rights reserved.
User manual
Rev. 1 — 23 June 2016
9 of 28
Jumper
Default setting
Comment
J8
(3-pin)
2-3
This jumper is used to select bus mode
1-2: select normal I2C or SPI addressable bus mode
2-3: select SPI daisy-chain bus mode for PCA9745B
J9
(5x2-pin)
9-10
This 5x2 jumper is used to select input value for pin 3
Open: floating
1-2: select V
DD
3-4: select pull-up with 31.6K
5-6: select pull-down with 34.8K
7-8: select GND
9-10: SDO for last slave device of PCA9745B in SPI daisy-chain
J10
(5x2-pin)
9-10
This 5x2 jumper is used to select input value for pin 4
Open: floating
1-2: select V
DD
3-4: select pull-up with 31.6K
5-6: select pull-down with 34.8K
7-8: select GND
9-10: CSN (Chip Select) SPI bus mode for PCA9745B
J11
(2-pin)
Short
Short: force /OE (pin5) to GND, to enable LEDs output
Open: 10K pull-up /OE (pin5) to V
DD
when apply external clock for
blinking/dimming on TP4 (test point)
J12, J16 J19,
J22
(2-pin)
Short
These jumpers are used to open the WHT_LED1 or RGB_LED1
J12 to control white LED, J16 to control Red LED, J19 to control Green
LED, J22 to control Blue LED
Open: connect current meter to measure one of the LEDs output current or
open one of the LEDs output for detecting an LED open condition in one of
EFLAGn register
Short: normal operation for WHT_LED1 and RGB_LED1
J13
(3-pin)
1-2
(V
LED
= +3.3V)
This jumper is used to select LED supply voltage
1-2: 3.3V for all LEDs supply voltage
2-3: 5V for all LEDs supply voltage
Open (no jumper): select external voltage from J20 (≤ +20V) and J24
(GND)
J14, J18 (2-pin) Open
These jumpers are used to merge the LED[0:2] outputs together for driving
higher LED current.
Open: normal operation for the LED[0:2]
Short: When short J14/J18 and open J16/J19 to combine LED[0:2] outputs
to drive LED0. When short J14 only and open J16 to combine LED[0:1]
outputs to drive LED0
J15, J17 J21,
J23
(2-pin)
Open
These jumpers are used to short the WHT_LED1 or RGB_LED1
J15 to control white LED, J17 to control Red LED, J23 to control Green
LED, J21 to control Blue LED
Open: normal operation for WHT_LED1 and RGB_LED1
Short: to short one of the LEDs for detecting an LED short condition in one
of EFLAGn register
J20
(2-pin)
+20V
Input
External ≤ +20V input for LEDs supply voltage
The J13 must be OPEN to supply this ≤ +20V external voltage to all LEDs.
