Datasheet LTC4315 (Analog Devices) - 6

LTC4315
PIN FUNCTIONS ACC (Pin 5):
Three-State Acceleration Strength Selector.
READY (Pin 7):
Connection Ready Status Output. This This pin controls the current strength of the rise time open drain N-channel MOSFET output pulls low when accelerators on both the input and output sides. Rise the input and output sides are disconnected. READY is time accelerators (RTAs) are disabled if ACC is high, pulled high when ENABLE is high and a connection has in current source mode if ACC is open and in the slew been established between the input and output. Connect limited switch mode if ACC is low. See Table 1 in the a pull-up resistor, typically 10k, from this pin to the bus Applications Information section. Grounding VCC2 selec- pull-up supply. Leave open or tie to GND if unused. tively disables the output side RTAs independent of the ACC
SCLIN (Pin 4):
Serial Bus 1 Clock Input/Output. Connect setting. this pin to the SCL line on the upstream bus. Connect an
DISCEN (Pin 2):
Enable Input to Disconnect Stuck Bus. external pull-up resistor or current source between this When this pin is high, stuck busses are automatically pin and the bus supply. The bus supply must be ≥ VCC disconnected after a timeout period of 45ms and FAULT if rise time accelerators are enabled. Do not leave open. is pulled low. Up to sixteen clock pulses are subsequently
SCLOUT (Pin 3):
Serial Bus 2 Clock Input/Output. Con- applied to SCLOUT. When DISCEN is low, stuck busses nect this pin to the SCL bus segment where stuck low are neither disconnected nor clocked but FAULT is pulled recovery is desired. Connect an external pull-up resistor low. Connect to GND if unused. or current source between this pin and the bus supply.
ENABLE (Pin 1):
Connection Enable Input. When driven The bus supply must be ≥ VCC2 if rise time accelerators low, the ENABLE pin isolates SDAIN and SCLIN from are enabled. Do not leave open. SDAOUT and SCLOUT, asserts READY low, disables rise
SDAIN (Pin 9):
Serial Bus 1 Data Input/Output. Connect time accelerators and inhibits automatic clock and stop bit this pin to the SDA line on the upstream bus. Connect an generation during a bus stuck low fault condition. When external pull-up resistor or current source between this pin driven high, the ENABLE pin connects SDAIN and SCLIN and the bus supply. The bus supply must be ≥ V to SDAOUT and SCLOUT after a stop bit or bus idle has CC if rise time accelerators are enabled. Do not leave open. been detected on both busses. Driving ENABLE high also enables automatic clock generation during a fault condition,
SDAOUT (Pin 10):
Serial Bus 2 Data Input/Output. Con- if DISCEN is tied high. During a fault condition, a rising nect this pin to the SDA bus segment where stuck low edge on the ENABLE pin forces a connection between recovery is desired. Connect an external pull-up resistor SDAIN and SDAOUT and SCLIN and SCLOUT. When using or current source between this pin and the bus supply. the LTC4315 in a Hot Swap™ application with staggered The bus supply must be ≥ VCC2 if rise time accelerators pins, connect a 10k resistor between ENABLE and GND are enabled. Do not leave open. to ensure correct functionality. Connect to VCC if unused.
VCC (Pin 12):
Power Supply Voltage. Power this pin from
Exposed Pad (DE12 Package Only):
Exposed pad may a supply between 2.9V and 5.5V. Bypass with at least be left open or connected to device GND. 0.01μF to GND.
FAULT (Pin 8):
Stuck Bus Fault Output. This open drain
VCC2 (Pin 11):
SDAOUT, SCLOUT Rise Time Accelerator N-channel MOSFET output pulls low if a simultaneous Power Supply Voltage. When powering VCC2, use a supply high on SCLOUT and SDAOUT does not occur in 45ms. In voltage ranging from 2.25V to 5.5V and bypass with at normal operation FAULT is high. Connect a pull-up resis- least 0.01μF to GND. Output side rise time accelerators are tor, typically 10k, from this pin to the bus pull-up supply. active if VCC2 ≥ 2.25V and ACC is low or open. Grounding Leave open or tie to GND if unused. VCC2 disables output side rise time accelerators indepen- dent of the state of ACC.
GND (Pin 6):
Device Ground. 4315f 6 Document Outline FEATURES DESCRIPTION APPLICATIONS TYPICAL APPLICATION ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION ORDER INFORMATION ELECTRICAL CHARACTERISTICS TYPICAL PERFORMANCE CHARACTERISTICS PIN FUNCTIONS BLOCK DIAGRAM OPERATION APPLICATIONS INFORMATION PACKAGE DESCRIPTION TYPICAL APPLICATION RELATED PARTS