LED7708 STMicroelectronics, LED7708 Datasheet - Page 31

• Manufacturer Part Number: LED7708
• Description: LED Lighting Drivers 16 Ch 85mA LED 3.6 to 36V 250kHz
• Manufacturer: STMicroelectronics

Specifications of LED7708

• Rohs: yes

LED7708
8.5.4
Brightness data formats
The format for the brightness data is chosen by acting on the BDFS (brightness data format
selector) and the BRLS (brightness register length selector) bits of the DEVCFG1 register.
Table 13.
16x16-bit data format (BDFS=0, BRLS=X)
The brightness registers BRT01:BRT16 are sequentially loaded at the end of 16-bit write
operations. The LE is managed to encode two serial keys: one for the so called “data latch”
operation and another to encode the final “global latch” operation. Therefore, a complete
brightness data transfer to the LED7708 consists of 15 “data latch” operations followed by a
single “global latch” operation.
If the 4096 steps (12-bit) brightness control is used (BRLS low), the four most significant bits
of each brightness register are unused. The brightness registers are written from BRT16 to
BRT01 with auto-decrement after each write operation (the LE signal of the last write
operation to BRT01 must encode a “global latch”).
Figure 9.
BDFS
0
0
1
1
Brightness data formats
16-bit data format, write operation to the brightness register
BRLS
0
1
0
1
Doc ID 022698 Rev 1
(the 4 most significant bits are not used)
Brightness data format
Recommended operating conditions
16x16, 12-bit
16x16, 16-bit
192x1, 12-bit
256x1, 16-bit
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