LTC3220-1 Linear Technology Corporation, LTC3220-1 Datasheet
LTC3220-1
Related parts for LTC3220-1
LTC3220-1 Summary of contents
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... The fi rst dropout switches the parts into 1.5x mode and a subsequent dropout switches the LTC3220/LTC3220-1 into 2x mode. The parts reset to 1x mode whenever a data bit is updated via the I L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ...
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... LTC3220/LTC3220-1 ABSOLUTE MAXIMUM RATINGS (Notes CPO to GND ................................ –0. ULED1-ULED18 to GND ............................... –0. SDA, SCL, RST............................–0.3V to (DV I (Continuous) (Note 2) ..................................360mA CPO I (Note 2) ..................................................25mA ULED1-18 CPO Short-Circuit Duration .............................. Indefi nite Operating Temperature Range (Note 3).... –40°C to 85°C Storage Temperature Range ................... – ...
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... Clock High Period HIGH t Clock Data Fall Time f t Clock Data Rise Time r t Spike Supression Time SP LTC3220/LTC3220-1 l The denotes the specifi cations which apply over the full operating = 3V, RST = high 2.2μ 4.7μ 25° 3.6V CONDITIONS ULED Data Register Programmed to ...
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... Note 2: Based on long term current density limitations. Note 3: The LTC3220/LTC3220-1 are guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls ...
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... CPO IN (I – VIN CPO 300 360 0 60 120 180 I (mA) CPO 3220 G12 LTC3220/LTC3220 25°C unless otherwise noted. A Oscillator Frequency vs V Voltage CPO IN 810 800 790 3.2V 780 3.1V 3V 770 760 T = 85°C A 750 740 730 240 ...
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... Connect unused outputs to ground. DV (Pin 10): Supply Voltage for All digital I/O lines. This CC pin sets the logic reference level of the LTC3220/LTC3220-1. DV will reset the data registers when set below the CC undervoltage lockout threshold. A 0.1μF X5R or X7R ceramic capacitor should be connected to ground. ...
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... SDA 12 SCL 11 27 850kHz OSCILLATOR – + 1.22V CONTROL LOGIC MASTER/SLAVE REG SHIFT REGISTER ULED18 ULED17 ULED16 ULED15 ULED14 ULED13 LTC3220/LTC3220 EXPOSED C1P C1M C2P C2M PAD 29 CPO CHARGE PUMP 28 ULED1 1 ULED2 2 ULED3 3 ULED4 4 ULED5 5 18 ULED6 18 UNIVERSAL ...
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... V is connected directly to CPO. This mode provides IN maximum effi ciency and minimum noise. The LTC3220/ LTC3220-1 will remain in 1x mode until an LED current source drops out. Dropout occurs when a current source www.DataSheet4U.com voltage becomes too low for the programmed current to be supplied. When dropout is detected, the LTC3220/ LTC3220-1 will switch into 1.5x mode. The CPO voltage will then start to increase and will attempt to reach 1.5× ...
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... OL nifi cant overall increase in available current is achieved. Mode Switching The LTC3220/LTC3220-1 will automatically switch from 1x mode to 1.5x mode and subsequently to 2x mode whenever a dropout condition is detected at an LED pin. Dropout occurs when a current source voltage becomes too low for the programmed current to be supplied ...
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... Serial Port The microcontroller compatible I all of the command and control inputs for the LTC3220/ LTC3220-1. Data on the SDA input is loaded on the rising edge of SCL loaded fi rst and D0 last. There are 20 data registers, one address register and one sub-ad- dress register. Once all address bits have been clocked into the address register, an acknowledge occurs ...
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... The LTC3220/LTC3220-1 are receive-only (slave) devices. There are two I address is 0011100 and the LTC3220-1 I 0011101. The I the LTC3220 and LTC3220-1. Write Word Protocol Used By the LTC3220/LTC3220 Slave Address Wr A *Sub-Address A Data Byte S = Start Condition Write Bit = Acknowledge Stop Condition *The sub-address uses only the fi ...
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... LTC3220/LTC3220-1 OPERATION Sub-Address Byte MSB www.DataSheet4U.com ...
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... Unused GB4 GB3 GB2 Gradation counts down Gradation counts up Blink Period D2 (GB2) 0.625s 1.25s 0 0.156s 1.25s 0 0.625s 2.5s 1 0.156s 2.5s 1 LTC3220/LTC3220-1 LSB Bit 2 Bit 1 Bit LSB D1 ...
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... I C device. Byte Format Each byte sent to the LTC3220/LTC3220-1 must be 8 bits long followed by an extra clock cycle for the Acknowledge bit to be returned by the LTC3220/LTC3220-1. The data should be sent to the LTC3220/LTC3220-1 most signifi cant bit (MSB) fi rst. ...
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... OPERATION Bus Write Operation The master initiates communication with the LTC3220/ LTC3220-1 with a Start condition and a 7-bit address fol- lowed by the Write Bit R the address matches that of the LTC3220/LTC3220-1, the LTC3220/LTC3220-1 return an Acknowledge. The master should then deliver the most signifi cant sub-address byte for the data register to be written ...
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... The output ripple in 2x mode is very small due to the fact that load current is supplied on both cycles of the clock. Both type and value of the output capacitor can signifi cantly affect the stability of the LTC3220/LTC3220-1. As shown in the Block Diagram, the LTC3220/LTC3220-1 use a control loop to adjust the strength of the charge pump to match 16 the required output current ...
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... PCB runs. Magnetic fi elds can also be generated if the fl ying capaci- tors are not close to the LTC3220/LTC3220-1 (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 LTC3220/LTC3220-1 pins ...
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... LED currents. At moderate to high output power, the quiescent current of the LTC3220/LTC3220-1 is negligible and the expres- sion above is valid. Once dropout is detected at any LED pin, the LTC3220/ LTC3220-1 enable the charge pump in 1.5x mode. ...
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... Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC3220/LTC3220-1 BOTTOM VIEW—EXPOSED PAD 0.05 ...
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... LTC3220/LTC3220-1 TYPICAL APPLICATION Cellular Phone Multi-Display LED Controller with Auxiliary Current Source Output 2.2μF 2.2μF C1P C1M C2P C2M V V CPO IN IN 2.2μF LTC3220 LTC3220-1 DV ULED1- 0.1μF www.DataSheet4U.com SCL/SDA RST GND RELATED PARTS PART NUMBER DESCRIPTION LTC3205 250mA, 1MHz, Multi-Display LED Controller ...