Datasheet LT8697 (Analog Devices) - 10
| Manufacturer | Analog Devices |
| Description | USB 5V 2.5A Output, 42V Input Synchronous Buck with Cable Drop Compensation |
| Pages / Page | 30 / 10 — PIN FUNCTIONS PG (Pin 19):. RCBL (Pin 23):. USB5V (Pin 20):. ICTRL (PIN … |
| File Format / Size | PDF / 502 Kb |
| Document Language | English |
PIN FUNCTIONS PG (Pin 19):. RCBL (Pin 23):. USB5V (Pin 20):. ICTRL (PIN 24):. ISP (Pin 21):. ISN (Pin 22):
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Text Version of Document
LT8697
PIN FUNCTIONS PG (Pin 19):
The PG pin is the open-drain output of an
RCBL (Pin 23):
Cable Drop Compensation Program Pin. internal window comparator. PG remains low until the A resistor RCBL tied from RCBL to ground programs cable USB5V pin is within ±9% of the final regulation voltage drop compensation by setting the USB5V input current. and there are no fault conditions. The PG transition delay RCBL can source 1mA. Excessive capacitive loading on is approximately 40µs. PG is valid when VIN is above 3.4V RCBL can degrade load transient response. Isolate load regardless of the EN/UV state. capacitance on this pin by tying a 100k resistor between
USB5V (Pin 20):
The LT8697 regulates the USB5V pin to RCBL and the capacitive load. The RCBL load monitor 5V. For cable drop compensation, the USB5V pin input output is valid when the LT8697 is enabled, otherwise the current is proportional to the sensed output current. The output is zero. Float RCBL if neither the current monitor USB5V ESD cell clamps to 9V. To allow the LT8697 output nor the cable drop compensation feature is desired. to survive a short to 30V, the 10k RCDC resistor must be
ICTRL (PIN 24):
Current Adjustment Pin. ICTRL adjusts in place between the USB5V pin and the output to limit the maximum VISP – VISN drop before the LT8697 limits the current into this pin. the output current. Connect directly to INTVCC or float for
ISP (Pin 21):
Current Sense (+) Pin. This is the non-inverting a full scale VISP – VISN threshold of 48mV or apply values input to the current sense amplifier. between ground and 1V to modulate the output current limit. There is an internal 2µA pull-up current on this pin.
ISN (Pin 22):
Current Sense (–) Pin. This is the inverting Float or tie to INTVCC when unused. input to the current sense amplifier.
GND (Exposed Pad Pin 25):
Ground. The exposed pad must be connected to the negative terminal of the input capacitor and soldered to the PCB for proper operation and in order to lower the thermal resistance. 8697fb 10 For more information www.linear.com/LT8697 Document Outline Features Applications Typical Application Absolute Maximum Ratings Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
PIN FUNCTIONS PG (Pin 19):
The PG pin is the open-drain output of an
RCBL (Pin 23):
Cable Drop Compensation Program Pin. internal window comparator. PG remains low until the A resistor RCBL tied from RCBL to ground programs cable USB5V pin is within ±9% of the final regulation voltage drop compensation by setting the USB5V input current. and there are no fault conditions. The PG transition delay RCBL can source 1mA. Excessive capacitive loading on is approximately 40µs. PG is valid when VIN is above 3.4V RCBL can degrade load transient response. Isolate load regardless of the EN/UV state. capacitance on this pin by tying a 100k resistor between
USB5V (Pin 20):
The LT8697 regulates the USB5V pin to RCBL and the capacitive load. The RCBL load monitor 5V. For cable drop compensation, the USB5V pin input output is valid when the LT8697 is enabled, otherwise the current is proportional to the sensed output current. The output is zero. Float RCBL if neither the current monitor USB5V ESD cell clamps to 9V. To allow the LT8697 output nor the cable drop compensation feature is desired. to survive a short to 30V, the 10k RCDC resistor must be
ICTRL (PIN 24):
Current Adjustment Pin. ICTRL adjusts in place between the USB5V pin and the output to limit the maximum VISP – VISN drop before the LT8697 limits the current into this pin. the output current. Connect directly to INTVCC or float for
ISP (Pin 21):
Current Sense (+) Pin. This is the non-inverting a full scale VISP – VISN threshold of 48mV or apply values input to the current sense amplifier. between ground and 1V to modulate the output current limit. There is an internal 2µA pull-up current on this pin.
ISN (Pin 22):
Current Sense (–) Pin. This is the inverting Float or tie to INTVCC when unused. input to the current sense amplifier.
GND (Exposed Pad Pin 25):
Ground. The exposed pad must be connected to the negative terminal of the input capacitor and soldered to the PCB for proper operation and in order to lower the thermal resistance. 8697fb 10 For more information www.linear.com/LT8697 Document Outline Features Applications Typical Application Absolute Maximum Ratings Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
