STEVAL-TLL004V1 STMicroelectronics, STEVAL-TLL004V1 Datasheet - Page 21

• Manufacturer Part Number: STEVAL-TLL004V1
• Description: BOARD EVAL FLASH DRIVER STCF03
• Manufacturer: STMicroelectronics

Specifications of STEVAL-TLL004V1

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-8431

STCF03
8.5
Table 11.
8.6
8.7
Figure 13. Flash and Torch current vs. dimming value
Note:
Power ON, SHUTDOWN
MODE
SUB ADD=01
(write mode)
DIM_REG
RESET Value
FTIM_0~3
This 4bit register defines the maximum flash duration. It is intended to limit the energy
dissipated by the LED to a maximum safe value or to leave to the STCF03 the control of the
flash duration during normal operation. Values from 0~15 correspond to 0~1.5 s (100 ms
steps). The timing accuracy is related to the internal oscillator frequency that clocks the
flash time counter (+/- 20 %). Entering flash mode (either by soft or hard triggering) activates
the flash time counter, which begins counting down from the value loaded in the F_TIM
register. When the counter reaches zero, flash mode is stopped by resetting TRIG_EN bit,
and simultaneously the ATN pin is set to true (LOW) to alert the microprocessor that the
maximum time has been reached. FTIM value remains unaltered at the end of the count.
Dimming register
TDIM_0~3
These 4 bits define the LED current in torch mode with 16 values fitting an exponential law.
Max torch current value is 25% of max flash current.
FDIM_0~3
These 4 bits define the LED current in flash mode with 16 values fitting an exponential law.
The max value of the current is set by the external resistors R
LED current values refer to R
TDIM_3
MSB
0
TDIM_2
0
FL
Doc ID 13169 Rev 7
=0.27 Ω, R
TDIM_1
0
TDIM_0
TR
=1.8 Ω
0
Current Step Coefficient - 1.19
FDIM_3
(Figure
0
Description of internal registers
13)
FL
FDIM_2
and R
0
TR
FDIM_1
.
(Figure
0
13)
FDIM_0
LSB
0
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