ltc3210-2 Linear Technology Corporation, ltc3210-2 Datasheet
ltc3210-2
Related parts for ltc3210-2
ltc3210-2 Summary of contents
Page 1
... The charge pump optimizes effi ciency based on the volt- age across the LED current sources. The part powers mode and will automatically switch to boost mode whenever any enabled LED current source begins to enter dropout. The LTC3210-2/LTC3210-3 are available in a 3mm × 3mm 16-lead QFN package. MAIN CAM C4 2.2μ ...
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... T ENM = high, unless otherwise noted. PARAMETER V Operating Voltage BAT I Operating Current VBAT V Shutdown Current BAT MLED1, MLED2, MLED3 and MLED4 (LTC3210-2 Only) Current LED Current Ratio ( MLED RM LED Dropout Voltage LED Current Matching 2 (Note 1) I (Note 2) ......................................................500mA CLED + 0 ...
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... Low Time to Shutdown (ENC, ENM = Low) Current Source Enable Time (ENC, ENM = High) (Note 5) Note 3: The LTC3210-2/LTC3210-3 are guaranteed to meet performance specifi cations from 0°C to 70°C. Specifi cations over the –40°C to 85°C ambient operating temperature range are assured by design, characterization and correlation with statistical process controls. Note 4: 1.5x mode output impedance is defi ...
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... LTC3210-2/LTC3210-3 TYPICAL PERFORMANCE CHARACTERISTICS Dropout Time from Shutdown 5.1V 2X CPO 1.5X 1V/DIV 1X EN 2V/DIV MODE RESET 321023 G01 500μs/DIV 2x CPO Ripple V = 3.6V BAT I = 200mA CPO C = 2.2μF CPO V CPO 20mV/DIV AC COUPLED 321023 G04 500ns/DIV 1.5x Mode CPO Voltage vs Load Current 4 2.2μF 4 3.3V BAT ...
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... V VOLTAGE (V) BAT ) CPO 400 360 320 280 240 200 160 120 80 40 300 400 500 321023 G16 LTC3210-2/LTC3210 25°C unless otherwise stated. A Oscillator Frequency vs V Voltage BAT 850 840 T = 25°C A 830 820 T = 85°C A 810 800 T = –40°C ...
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... LTC3210-2/LTC3210-3 TYPICAL PERFORMANCE CHARACTERISTICS MLED Pin Current vs MLED Pin Voltage 3.6V BAT 0.00 0.02 0.04 0.06 0.08 0.10 MLED PIN VOLTAGE (V) MLED Current vs ENM Strobe Pulses 3.6V BAT RM = 30. NUMBER OF ENM STROBE PULSES 6 400 350 300 ...
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... The current to each LED output is set via the ENM input, and the programming resistor connected between RM and GND. LTC3210-2/LTC3210-3 MLED4 (Pin 7, LTC3210-2 Only): Output. MLED4 is the fourth main current source output available only on the LTC3210-2 product. The LED is connected between CPO (anode) and MLED4 (cathode). The current to MLED4 is set via the ENM input and the programming resistor connected between RM and GND ...
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... TIMER ENABLE MAIN 5-BIT 5- BIT DOWN LINEAR COUNTER DAC TIMER SHUTDOWN TIMER ENABLE CAM 3-BIT 3- BIT DOWN LINEAR COUNTER DAC C2M 13 12 GND 2 CPO ENABLE CP 4 MLED1 5 MLED2 MLED 4 CURRENT SOURCES 6 MLED3 MLED4 7 (LTC3210-2 ONLY) CLED 11 CLED CURRENT SOURCE 321023 BD 321023fa ...
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... CPO. This mode BAT provides maximum effi ciency and minimum noise. The LTC3210-2/LTC3210-3 will remain in 1x mode until an LED current source drops out. Dropout occurs when a current source voltage becomes too low for the programmed current to be supplied. When dropout is detected, the LTC3210-2/LTC3210-3 will switch into 1 ...
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... Table 1. Charge Pump Output Regulation Voltages Charge Pump Mode 1. When the LTC3210-2/LTC3210-3 operate in either 1.5x mode or 2x mode, the charge pump can be modeled as a Thevenin-equivalent circuit to determine the amount of to slowly charge the current available from the effective input voltage and ef- fective open-loop output resistance, R Figure 2 ...
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... OL shown in Figure 3 and Figure 4. Shutdown Current In shutdown mode all the circuitry is turned off and the LTC3210-2/LTC3210-3 draw a very low current from the V supply. Furthermore, CPO is weakly connected to V BAT The LTC3210-2/LTC3210-3 enter shutdown mode when both the ENM and ENC pins are brought low at 150μ ...
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... ESR. Therefore, is the output storage ceramic capacitors are recommended for low ESR. Input noise can be further reduced by powering the LTC3210-2/ LTC3210-3 through a very small series inductor as shown in Figure 5. A 10nH inductor will reject the fast current notches, thereby presenting a nearly constant current load to the input power supply ...
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... PCB runs. Magnetic fi elds can also be generated if the fl ying capacitors are not close to the LTC3210-2/LTC3210-3 (i.e., the loop area is large). To decouple capacitive energy transfer, a Faraday shield may be used. This is a grounded PCB trace between the sensitive node and the LTC3210-2/LTC3210-3 pins ...
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... P IN The effi ciency of the LTC3210-2/LTC3210-3 depends upon the mode in which it is operating. Recall that the LTC3210-2/ LTC3210-3 operates as a pass switch, connecting V CPO, until dropout is detected at the LED pin. This feature provides the optimum effi ciency available for a given input voltage and LED forward voltage. When it is operating as a switch, the effi ...
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... Plastic QFN (3mm × 3mm) (Reference LTC DWG # 05-08-1691) 0.70 ±0.05 PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC 0.75 ± 0.05 (4 SIDES) 1.45 ± 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LTC3210-2/LTC3210-3 BOTTOM VIEW—EXPOSED PAD PIN 1 NOTCH R = 0.20 TYP R = 0.115 OR 0.25 × 45° CHAMFER TYP 15 16 0.40 ± 0. (UD16) QFN 0904 0.25 ± 0.05 ...
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... LTC3210-2/LTC3210-3 TYPICAL APPLICATION C1P V V BAT BAT C1 2.2μF ENM ENM ENC ENC RM RELATED PARTS PART NUMBER DESCRIPTION LT1618 Constant Current, 1.4MHz, 1.5A Boost Converter LTC3205 250mA, 1MHz, Multi-Display LED Controller LTC3206 400mA, 800kHz, Multi-Display LED Controller LTC3208 High Current Software Confi gurable Multi-Display ...