AS3691A-ZQFT ams

AS3691 4 Precision 400mA Current Sources for RGB and Single Color LEDs The AS3691 (AS3691A and AS3691B) features four high General Description precision current sinks to drive up to four LED strings. Each of the current sinks can sustain up to 15V and drive up to 400mA. Every channel can be controlled independently by PWM inputs. To ensure best efficiency AS3691 is able to regulate any external LED power supply (DC-DC converter) to its perfect needs (patented feedback function). The full scale current is set by external resistor. Ordering Information and Content Guide appear at end of datasheet. Key Benefits & Features The benefits and features of the AS3691 4 Precision 400mA Current Sources for RGB and Single Color LEDs, are listed below: Figure 1: Added Value of Using AS3691 Benefits Features 4 up to 0.4A constant current outputs Fully flexible current outputs / no SW effort Programmable with external resistors 4 independent PWM inputs Perfect color uniformity Absolute current accuracy 0.5% (1) Automatic Supply Regulation to reduce power Unique DC-DC feedback function dissipation Very wide output voltage current source voltage compliance Maximum number of LEDs per channel Down to 0.41V (2) Up to 15V On-chip safety features Integrated overtemperature protection Package options: Easy integration due to several package QFN24 (4 4mm) types including thermal enhanced eP-TSSOP eP-TSSOP Note(s): 1. ams system patent 2. 15V is sufficient for most applications as the AS3691 does not switch off the LED current completely ams Datasheet Page 1 v2-07 2016-Jan-21 Document FeedbackAS36 91 Gene ral Des c rip t ion Applications General Lighting Backlighting RGB Backlighting for LCD TV/Monitors with White Color Balancing Application Diagrams Figure 2: Application Diagram of AS3691 for Single Color Lighting VDD VDD Csup 100nF Rvdd Cvdd 100nF UV UV VREG UV1 CURR1 UV2 CURR2 UV3 CURR3 UV4 CURR4 AS3691 Vc Vc Vc Vc D1 Ref T1 T2 T3 T4 I1 I2 I3 I4 Overtemp R1 R2 R3 R4 Pad VSS ON1 RFB1 RES1 ON2 RFB2 RES2 ON3 RFB3 RES3 ON4 RFB4 RES4 Ri1 Ri2 Ri3 Ri4 VSS VSS PWM PWM Page 2 ams Datasheet Document Feedback v2-07 2016-Jan-21