LTC4309 Linear Technology, LTC4309 Datasheet
LTC4309
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LTC4309 Summary of contents
Page 1
... During insertion, the SDA and SCL lines are precharged minimize bus disturbances. When driven high, the ENABLE input allows the LTC4309 to connect after a stop bit or bus idle. Driving ENABLE low breaks the connection between SDAIN and SDAOUT, SCLIN and SCLOUT. READY is an open drain output which indicates that the backplane and card sides are connected ...
Page 2
... For more information on tape and reel specifi cations, go to: 2 (Note 1, 6) Operating Temperature LTC4309C ................................................ 0°C to 70°C LTC4309I.............................................. –40°C to 85°C Storage Temperature Range (DE)........... –65°C to 125°C Storage Temperature Range (GN) .......... –65°C to 150°C Lead Temperature (Soldering, 10 sec) GN Package ...................................................... 300° ...
Page 3
... I = 3mA 2.3V READY READY = 5.5V CC (Note 3) (Note 3) (Note 3) (Note 3) (Note 3) (Note 3) (Note 3) 2. SDA, SCL, Driven SDA, SCL = 0.2V CC2 V ≥ 2. < 2.9V CC LTC4309 MIN TYP MAX UNITS l 2.3 5.5 l 1.8 5 900 1400 μA l 190 250 μA l 140 180 μ ...
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... LTC4309 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER V SDA, SCL Logic Input Threshold Voltage THR(HYST) Hysteresis C Digital Input Capacitance SDAIN, IN SDAOUT, SCLIN, SCLOUT I Input Leakage Current LEAK V Output Low Voltage OL V Buffer Input Logic Low Voltage ILMAX www ...
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... 3. 100 –50 – TEMPERATURE (°C) 4309 G05 C = 50pF 2.7k PULLUPIN R = 2.7k PULLUPOUT 600 800 1000 4309 G08 LTC4309 T = 25° 3.3V 3.3V unless A CC CC2 otherwise noted. I Enabled Current vs CC2 Temperature 220 200 V = 5.5V CC 180 V = 3.3V 160 CC 140 V = 2.3V CC 120 ...
Page 6
... N-channel MOSFET output pulls low after 30ms when there is a bus stuck low condition on the output pins of the LTC4309. In normal operation FAULT is high. Connect a pull-up resistor, typically 10k, from this pin to the bus pull-up supply. This pin can be left open if unused. ...
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... CC2 CONNECT I BOOSTSDA PRECHARGE CC2 PC CONNECT CONNECT CONNECT I BOOSTSCL 30ms TIMER + LOGIC – + – + – 95μs UVLO DELAY LTC4309 V CC 8mA I BOOSTSDA SLEW RATE DETECTOR 100k 8mA 100k I BOOSTSCL SLEW RATE DETECTOR + 1.65V/1.6V – 1.35V/1.3V + 1.65V/1.6V – ...
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... Input to Output Offset Voltage When a logic low voltage is driven on any of the LTC4309’s data or clock pins, the LTC4309 regulates the voltage on the other side of the device to a slightly higher voltage activate the rise time accelerators on ...
Page 9
... In addition, after at least 40μ clock pulses at 8.5kHz (typi- and cal) is generated on the SCLOUT pin by the LTC4309 attempt to free the stuck low bus. Once the clock pulses have completed, a stop bit is generated on the SCLOUT and SDAOUT pins to reset all devices on the bus ...
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... TM , capacitance Repeater/Bus Extender Applications Users who wish to connect two 2-wire systems separated by a distance can connecting two LTC4309s back- to-back, as shown in Figure 6. The I for 400pF maximum bus capacitance, severely limiting the length of the bus. The SMBus specification places no restriction on bus capacitance, but the limited impedances of devices connected to the bus require systems to remain small if rise time and fall time specifications are to be met ...
Page 11
... Level Shifting Applications Systems requiring different supply voltages for the backplane side and the card side can use the LTC4309 for bidirectional level shifting, as shown in Figure 6. The LTC4309 can level shift between bus pull-up supplies as low as 1.7V, with the accelerators disabled high as 5 ...
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... APPLICATIONS INFORMATION BACKPLANE CC2 10k 10k 10k SDA SCL FAULT READY ENA1 www.DataSheet4U.com ENAN Figure 4. The LTC4309 in an Application with a Staggered Connector. 12 BACKPLANE CARD CONNECTOR CONNECTORS I/O PERIPHERAL CARD 1 C2 0.01μ CC2 10k SDAIN SCLIN FAULT READY ENABLE R7 10k ...
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... R2 R3 10k 10k 10k SDA SCL FAULT READY ENA1 www.DataSheet4U.com ENAN Figure 5. The LTC4309 in an Application Where All the Pins Have the Same Length. 3. 10k 10k 10k 10k SDA1 SCL1 Figure 6. The LTC4309 in a Level Shifting Repeater/Bus Extender Application. ...
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... SDAOUT SDAIN www.DataSheet4U.com SCL1 SCLOUT SCLIN ACC GND Figure 7. The LTC4309 in a Repeater Application. The LTC4309’s Low Offset Allows Cascading of Multiple Devices. 2.5V SDA1 SCL1 Figure 8. The LTC4309 in a level shifting application where the bus supplies are different from ...
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... TYP * DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE INCHES (MILLIMETERS) ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE LTC4309 R = 0.115 0.40 0.10 TYP 7 12 PIN 1 NOTCH R = 0.20 OR ...
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... C1 C2 0. 10k 10k V V CC2 CC DISCEN ENABLE READY LTC4309 FAULT SDAIN SDAOUT SCLOUT SCLIN ACC GND 4309 F07 COMMENTS Low R : 35Ω Single Ended/70Ω Differential, Expandable Single or 16 Differential Channels Precision 50uA+/–2.5% Tolerance Over Temperature, 4 Selectable ...