STLD20CP1PQR STMicroelectronics, STLD20CP1PQR Datasheet - Page 9

• Manufacturer Part Number: STLD20CP1PQR
• Description: IC LED DRIVR BCKLGT FLASH 16-QFN
• Manufacturer: STMicroelectronics
• Type: Backlight, Flash, Movier

Specifications of STLD20CP1PQR

• Topology: PWM, Step-Up (Boost), Switched Capacitor (Charge Pump)
• Number Of Outputs: 2
• Internal Driver: Yes
• Type - Primary: Backlight, Flash/Torch
• Type - Secondary: White LED
• Frequency: 1.3MHz
• Voltage - Supply: 2.8 V ~ 6 V
• Voltage - Output: 17V
• Mounting Type: Surface Mount
• Package / Case: 16-QFN
• Operating Temperature: -40°C ~ 85°C
• Internal Switch(s): Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output / Channel: -
• Efficiency: -
• Other names: 497-6924-2; STLD20CP1PQR

6
6.1
6.2
Figure 4.
Application information
Step-up
The STLD20CP1 is a PWM controller working at a 1.3 MHz frequency, designed to function
in discontinuous mode. The LED current regulation for the backlighting is achieved by
connecting the FB_SU terminal at the top end of the external R
I
Shutdown and brightness control
The shutdown and brightness control functions are achieved by using the digital control pins
DM1 and DM2.
There are also other modes that can be used to perform dimming control on white LEDs.
The first is to use the truth table selection mode step-up that shows the behavior using a
preselected digital dimming control.
The second is a PWM dimming control mode, which is implemented by keeping a DMx pin
at a low or high value and the other DMx forcing a PWM digital signal up to 50 kHz with a
minimum duty cycle 5%. A 5% duty cycle corresponds to the minimum current and a 100%
duty cycle corresponds to full current. In cases where DM2 is a high value and DM1 is
forced with a PWM digital
If DM2 is held low and the PWM signal is applied on DM1
varies from 0 up to 60% of current.
PWM dimming method from 5% to 100%
LED
= V
FB_SU
/R
LED
(Figure
4), the dimming control varies from 5% to 100% of current.
(Figure
LED
5), the dimming control
resistance.
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