ISL97635AIRZ Intersil, ISL97635AIRZ Datasheet - Page 19

• Manufacturer Part Number: ISL97635AIRZ
• Description: IC LED DRVR WHT/RGB BCKLGT 24QFN
• Manufacturer: Intersil
• Type: Backlight, White LED, RGBr

Specifications of ISL97635AIRZ

• Topology: PWM, Step-Up (Boost)
• Number Of Outputs: 6
• Internal Driver: Yes
• Type - Primary: Automotive, Backlight
• Type - Secondary: RGB, White LED
• Frequency: 600kHz, 1.2MHz
• Voltage - Supply: 6 V ~ 24 V
• Voltage - Output: 34.5V
• Mounting Type: Surface Mount
• Package / Case: 24-VQFN
• Operating Temperature: -40°C ~ 85°C
• Current - Output / Channel: 35mA
• Internal Switch(s): Yes
• Efficiency: 91%
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PWM Brightness Control Register (0x00)
The Brightness control resolution has 256 steps of PWM
duty cycle adjustment. The bit assignment is shown in
Figure 23. All of the bits in this Brightness Control Register
can be read or write. Step 0 corresponds to the minimum
step where the current is less than 10µA. Step1 to step 255
represent the linear steps between 0.39% and 100% duty
cycle with approximately 0.39% duty cycle adjustment per
step.
• An SMBus Write Byte cycle to register 0x00 sets the PWM
ADDRESS
brightness level only if the backlight controller is in SMBus
0x00
0x01
0x02
0x03
0x07
0x08
0x09
PWM Brightness Control Register BRT[7..0] = 256 steps of DPWM duty cycle brightness control
Device Control Register
Fault/Status Register
Identification Register
DC Brightness Control Register
Configuration Register
Output Channel Mask / Fault
Readout Register
REGISTER
19
PWM_MD = PWM mode select bit (1 = absolute brightness, 0 = % change), default = 0
PWM_SEL = Brightness control select bit (1 = control by PWMI, 0 = control by SMBus), default = 0
BL_CTL = BL On/Off (1 = On, 0 = Off), default = 0
2_CH_SD = Two LED output channels are shutdown (1 = shutdown, 0 = OK)
1_CH_SD = One LED output channel is shutdown (1 = shutdown, 0 = OK)
BL_STAT = BL status (1 = BL On, 0 = BL Off)
OV_CURR = Input overcurrent (1 = Overcurrent condition, 0 = Current OK)
THRM_SHDN = Thermal Shutdown (1 = Thermal fault, 0 = Thermal OK)
FAULT = Fault occurred (Logic “OR” of all of the fault conditions)
MFG[3..0] = Manufacturer ID (16 vendors available. Intersil is vendor ID 9)
REV[2..0] = Silicon rev (Rev 0 through Rev 7 allowed for silicon spins)
BRTDC[7..0] = 256 steps of DC brightness control
VSC[1..0] = Short circuit thresholds selection
FSW[2] = Switching frequencies selection
CH[5..0] = Output Channel Read and Write. In Write, 1 = Channel Enabled, 0 = Channel Disabled.
In Read, 1 = Channel OK, 0 = Channel Not OK/Channel disabled
TABLE 2B. DATA BIT DESCRIPTIONS
VSC1
ISL97635A
0
1
1
FSW
PWM_MD PWM_SEL
0
1
X
1
0
F
F
VSC0
SW
SW
X
0
1
• An SMBus Read Byte cycle to register 0x00 returns the
• An SMBus setting of 0xFF for register 0x00 sets the
• An SMBus setting of 0x00 for register 0x00 sets the
• Default value for register 0x00 is 0xFF.
= 600kHz
= 1.2MHz
mode (see Table 3 Operating Modes selected by Device
Control Register Bits 1 and 2).
programmed PWM brightness level regardless of the
value of PWM_SEL.
backlight controller to the maximum brightness.
backlight controller to the minimum brightness output in
which the LED current is guaranteed to be less than 10µA.
1
0
0
DATA BIT DESCRIPTIONS
No VSC error detection
VSC = 3.1V ±15%
VSC = 8V ±15%
OPERATION
PWMI Mode
SMBus Mode
SMBus and PWMI mode with DPST
OPERATION
MODE
December 22, 2008
FN6564.2