ISL78171 Datasheet, PDF (23/29 Pages) Intersil Corporation – 6-Channel, 50mA Automotive LED Driver with Ultra-high Dimming Ratio and Phase Shift Control

ISL78171
Identification Register (0x03)
The ID register contains 3-bit fields to denote the LED driver
(always set to 1), manufacturer and the silicon revision of the
controller IC. The bit field widths allow up to 16 vendors with up
to 8 silicon revisions each. All of the bits in this register are
read-only.
• Vendor ID 9 represents Intersil Corporation
• The default value for Register 0x03 is 0xC8
The initial value of REV shall be 0. Subsequent values of REV will
increment by 1.
DC Brightness Control Register (0x07)
The DC Brightness Control Register 0x07 sets the LED current
level between 0% and 100% of the level set using the RSET pin.
When PWM dimming, the level set is the current during the on
time. This register allows users to have additional dimming
flexibility by:
1. Effectively achieving 16-bits of dimming control when DC
dimming is combined with PWM dimming
2. Achieving visual or audio noise free 8-bit DC dimming over
potentially noisy PWM dimming.
The bit assignment is shown in Figure 38. All of the bits in this
Register can be read or written. Steps 0 to 255 represent the
linear steps of DC current adjustment on-the-fly.
• An SMBus/I²C Write Byte cycle to Register 0x07 sets the DC
LED current level.
• An SMBus/I²C Read Byte cycle to Register 0x07 returns the DC
LED current.
• Default value for Register 0x07 is 0xFF.
REGISTER 0x03
ID REGISTER
LED PANEL
Bit 7 = 1
MFG3
Bit 6 (R)
MFG2
Bit 5 (R)
MFG1
Bit 4 (R)
MFG0
Bit 3 (R)
REV2
Bit 2 (R)
REV1
Bit 1 (R)
BIT ASSIGNMENT
MFG[3..0]
REV[2..0]
BIT FIELD DEFINITIONS
= Manufacturer ID. See “Identification Register
(0x03)” on page 23.
data 0 to 8 in decimal correspond to other vendors
data 9 in decimal represents Intersil ID
data 10 to 14 in decimal are reserved
data 15 in decimal Manufacturer ID is not
implemented
= Silicon rev (Rev 0 through Rev 7 allowed for silicon
spins)
FIGURE 37. DESCRIPTIONS OF ID REGISTER
REV0
Bit 0 (R)
REGISTER 0x07
DC BRIGHTNESS CONTROL REGISTER
BRTDC7
BRTDC6
BRTDC5
BRTDC4
BRTDC3
BRTDC2
BRTDC1
BRTDC0
Bit 7 (R/W) Bit 6 (R/W) Bit 5 (R/W) Bit 4 (R/W) Bit 3 (R/W) Bit 2 (R/W) Bit 1 (R/W) Bit 0 (R/W)
BIT ASSIGNMENT
BRTDC[7..0]
BIT FIELD DEFINITIONS
= 256 steps of DC brightness levels
FIGURE 38. DESCRIPTIONS OF DC BRIGHTNESS CONTROL REGISTER
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FN8602.0
June 15, 2015