LTC3212 Linear Technology, LTC3212 Datasheet
LTC3212
Available stocks
Related parts for LTC3212
LTC3212 Summary of contents
Page 1
... The charge pump shuts down to a high impedance mode to prevent LED leakage while the LTC3212 is off. Each LED may be individually turned on or off via a single pin interface. The current through the LEDs may be indi- vidually programmed with resistors or may share a single programming resistor ...
Page 2
... LEAD FREE FINISH TAPE AND REEL LTC3212EDDB#PBF LTC3212EDDB#TR Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: For more information on tape and reel specifications, go to: ...
Page 3
... Continuous operation above the specified maximum operating junction temperature may impair device reliability. Note 5: If the LTC3212 has been shut down, then the initial enable time is longer due to the bandgap settling time and the CPO output capacitor soft-start time. ...
Page 4
... LTC3212 Typical perForMance characTerisTics 1x Mode Charge Pump Resistance vs Temperature 6 50mA CPO 6 5 3.6V 5 4.2V IN 4.0 3.5 3.0 –40 – TEMPERATURE (°C) 3212 G04 Oscillator Frequency vs V Voltage IN 892 890 888 886 884 882 880 2.7 3.9 4.3 4.7 5.1 3.1 3.5 V (V) IN 3212 G07 2x Mode Voltage IN 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 3.1 3.5 2.7 ...
Page 5
... V ( (cathode). GND (Pin 10): This pin should be connected directly to a low impedance ground plane. V (Pin 12): Supply voltage for the LTC3212 bypassed with a low impedance ceramic capacitor to GND of at least 1µF of capacitance. Exposed Pad (Pin 13): GND. The Exposed Pad must be ...
Page 6
... AUTOSET GND 10 begins to drop out of regulation. When this drop out oc- curs the LTC3212 will switch to 2x mode after a soft-start period. The part will return to 1x mode when the part is IN shut down and reprogrammed. The current delivered through the LED load is controlled to CPO ...
Page 7
... CPO capacitor over a period of approximately 100µs. Charge Pump Strength When the LTC3212 operates in 2x mode, the charge pump can be modeled as a Thevenin equivalent circuit to determine the amount of current available from the effective input voltage and the effective open-loop output resistance, R ...
Page 8
... Mode Switching The LTC3212 will automatically switch from mode whenever it detects a LED driver is entering dropout. The part will wait approximately 140µs before switching to 2x mode. This delay will act as filtering to prevent the part from incorrectly switching to 2x mode due to a momen- tary glitch on the V entering shutdown mode and reprogramming ...
Page 9
... V , CPO Capacitor Selection IN The style and value of the capacitors used with the LTC3212 determine several important parameters such as regulator control loop stability, output ripple, charge pump strength and minimum start-up time. To reduce noise and ripple recommended that low ...
Page 10
... BAT since the input current will be very close to the sum of the LED currents. At moderate to high output power, the quiescent current of the LTC3212 is negligible and the expression above is valid. 0 Once dropout is detected at any LED pin, the LTC3212 enables the charge pump in 2x mode. ...
Page 11
... R = 0.05 (2 SIDES) TYP 2.00 ±0.10 (2 SIDES) 0.64 ± 0.10 (2 SIDES) 0.23 ± 0.05 0.75 ±0.05 0 – 0.05 BOTTOM VIEW—EXPOSED PAD MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE LTC3212 www.DataSheet4U.com 0.40 ± 0.10 TYP 7 12 PIN 0.20 OR 0.25 × 45° CHAMFER 6 1 (DDB12) DFN 0106 REV Ø ...
Page 12
... Internal Schottky ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 1µ CPO IN LTC3212 1µF LEDB LEDEN LEDR LEDG I SETB I LEDR = 10mA SETR LEDB = 15mA I SETG LEDG = 20mA 17 ...