Datasheet

LED_MODE
44
Resistors
to set
options
bq500410A
To 12-bit ADC
43
LOSS_THR
bq500410A
www.ti.com SLUSB96 – NOVEMBER 2012
Option Select Pins
Two pins (pin 43 and pin 44) on the bq500410A are allocated to program the Loss Threshold and the LED mode
of the device. At power up, a bias current is applied to pins LED_MODE and LOSS_THR and the resulting
voltage measured in order to identify the value of the attached programming resistor. The values of the operating
parameters set by these pins are determined using Table 4. For LED_MODE, the selected bin determines the
LED behavior based on Table 3; for the LOSS_THR, the selected bin sets a threshold used for parasitic metal
object detection (see Parasitic Metal Detection (PMOD) and Foreign Object Detection (FOD) section).
Figure 4. Option Programming
LED Modes
The bq500410A can directly drive two LED outputs (pin 7 and pin 8) through a simple current limit resistor
(typically 470 Ω), based on the mode selected. The two current limit resistors can be individually adjusted to tune
or match the brightness of the two LEDs. Do not exceed the maximum output current rating of the device.
The selection resistor connected between pin 44 and GND selects one of the desired LED indication schemes
presented in Table 3.
Table 3. LED Modes
OPERATIONAL STATES
LED LED
CONTROL SELECTION DESCRIPTION LED
POWER CHARGE PMOD or FOD
STANDBY FAULT
OPTION RESISTOR
TRANSFER COMPLETE WARNING
0 <36.5 kΩ LEDs off
LED1, Green Off Blink slow
(1)
On Off Off
1 42.2 kΩ Generic
LED2, Red Off Off Off On Blink fast
(2)
LED1, Green On Blink slow
(1)
On Off Off
2 48.7 kΩ Generic + standby
LED2, Red On Off Off On Blink fast
(2)
LED1, Green Off Off On Off Off
3 56.2 kΩ Generic Opt 1
LED2 Red Off On Off Blink fast
(2)
On
LED1, Green Off On Off Off Off
4 64.9 kΩ Generic Opt 2
LED2 Red Off Off Off On Blink fast
(2)
> 75 kΩ Reserved
(1) Blink slow = 0.625 Hz
(2) Blink fast = 2.5 Hz
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