Datasheet LTC4368 (Analog Devices) - 7
| Fabricante | Analog Devices |
| Descripción | 100V UV/OV and Reverse Protection Controller with Bidirectional Circuit Breaker |
| Páginas / Página | 22 / 7 — PIN FUNCTIONS Exposed Pad:. FAULT:. GATE:. SHDN:. GND:. OV:. UV:. RETRY:. … |
| Revisión | A |
| Formato / tamaño de archivo | PDF / 1.9 Mb |
| Idioma del documento | Inglés |
PIN FUNCTIONS Exposed Pad:. FAULT:. GATE:. SHDN:. GND:. OV:. UV:. RETRY:. VIN:. SENSE:. VOUT:
Versión de texto del documento
LTC4368
PIN FUNCTIONS Exposed Pad:
The exposed pad may be left open or con- current sink pulls down on the GATE output, thus quickly nected to device ground. disconnecting the load from the input. After a reverse cur-
FAULT:
Fault Indication Output. Connect to a pull-up resis- rent fault, when VOUT falls 100mV below VIN, the LTC4368 tor. This high voltage open drain output is pulled low if automatically turns on the external MOSFETs. A forward there is a voltage or current fault, if SHDN is low, or if overcurrent fault uses the RETRY pin to set the conditions V for reconnecting power to the load. Connect to VOUT if IN has not risen above VIN(UVLO). Leave unconnected if unused. unused.
GATE:
Gate Drive Output for External N-channel MOSFETs.
SHDN:
Shutdown Control Input. Assuming no voltage or An internal charge pump provides 35µA of pull-up current current faults, SHDN high enables the GATE charge pump and up to 13.1V of enhancement to the gate of an external which in turn enhances the gate of the external N-channel MOSFET. When turned off, GATE is pulled just below the MOSFETs. A low on SHDN generates a pull down on the lower of V GATE output with a 90µA current sink and places the IN or VOUT. When VIN goes negative, GATE is automatically connected to V LTC4368 in low current mode (5µA). If a forward overcur- IN. rent condition latches off the external MOSFETs (RETRY
GND:
Device Ground. grounded), the SHDN pin must be toggled low then high
OV:
Overvoltage Comparator Input. Connect this pin to an to re-enable the charge pump that enhances the external external resistive divider to set the desired V MOSFETs. If V IN overvolt- IN goes above 80V, the SHDN pin voltage age fault threshold. This input connects an accurate, fast must be kept below 80V. (1µs) comparator with a 0.5V rising threshold and 25mV
UV:
Undervoltage Comparator Input. Connect this pin to of hysteresis. When OV rises above its threshold, a 60mA an external resistive divider to set the desired VIN under- current sink pulls down on the GATE output. When OV voltage fault threshold. This input connects to an accu- falls back below 0.475V, and after a 32ms GATE turn-on rate, fast (1µs) comparator with a 0.5V falling threshold delay waiting period, the GATE charge pump is enabled. and 25mV of hysteresis. When UV falls below its thresh- The low leakage current on this input allows the use of old, a 60mA current sink pulls down on the GATE output. large valued resistors for the external resistive divider. When UV rises back above 0.525V, and after a 32ms GATE Connect to GND if unused. turn-on delay waiting period, the GATE charge pump is
RETRY:
Retry or Latch-Off Selection Input. Connect to enabled. The low leakage current on this input allows the ground to latch off the MOSFETs after a forward over- use of large valued resistors for the external resistive current fault. To turn the external MOSFETs back on, the divider. If unused and VIN is less than 80V, connect to SHDN pin must be toggled low then high. Connect RETRY VIN with a 510k resistor. to an external capacitor to configure a 5.5ms/nF delay
VIN:
Power Supply Input. Maximum protection range: before the MOSFETs automatically turn on again. Leave –40V to 100V. Operating range: 2.5V to 60V. This pin unconnected if unused. can be hot swapped and has a 2.2V UVLO.
SENSE:
Overcurrent Sense Input. Connect a current
VOUT:
Output Voltage Sense Input. Connect a current sense resistor between SENSE and VOUT. This input sense resistor between VOUT and SENSE. The GATE detects overcurrent faults in both directions: forward charge pump voltage is referenced to VOUT. It is used as at ΔVSENSE = 50mV, and reverse at ΔVSENSE = –50mV the charge pump input when VOUT is greater than approxi- (LTC4368-1 option) or ΔVSENSE = –3mV (LTC4368-2 mately 5V. The reverse current fault comparators require option). When an overcurrent fault is detected, a 60mA that VOUT rise above its 2.2V UVLO. VOUT cannot be hot swapped with supplies above 24V. Place at least 1µF from VOUT to GND. Rev A For more information www.analog.com 7 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Pin Functions Block Diagram Applications Information Related Parts Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Revision History Typical Application Related Parts
PIN FUNCTIONS Exposed Pad:
The exposed pad may be left open or con- current sink pulls down on the GATE output, thus quickly nected to device ground. disconnecting the load from the input. After a reverse cur-
FAULT:
Fault Indication Output. Connect to a pull-up resis- rent fault, when VOUT falls 100mV below VIN, the LTC4368 tor. This high voltage open drain output is pulled low if automatically turns on the external MOSFETs. A forward there is a voltage or current fault, if SHDN is low, or if overcurrent fault uses the RETRY pin to set the conditions V for reconnecting power to the load. Connect to VOUT if IN has not risen above VIN(UVLO). Leave unconnected if unused. unused.
GATE:
Gate Drive Output for External N-channel MOSFETs.
SHDN:
Shutdown Control Input. Assuming no voltage or An internal charge pump provides 35µA of pull-up current current faults, SHDN high enables the GATE charge pump and up to 13.1V of enhancement to the gate of an external which in turn enhances the gate of the external N-channel MOSFET. When turned off, GATE is pulled just below the MOSFETs. A low on SHDN generates a pull down on the lower of V GATE output with a 90µA current sink and places the IN or VOUT. When VIN goes negative, GATE is automatically connected to V LTC4368 in low current mode (5µA). If a forward overcur- IN. rent condition latches off the external MOSFETs (RETRY
GND:
Device Ground. grounded), the SHDN pin must be toggled low then high
OV:
Overvoltage Comparator Input. Connect this pin to an to re-enable the charge pump that enhances the external external resistive divider to set the desired V MOSFETs. If V IN overvolt- IN goes above 80V, the SHDN pin voltage age fault threshold. This input connects an accurate, fast must be kept below 80V. (1µs) comparator with a 0.5V rising threshold and 25mV
UV:
Undervoltage Comparator Input. Connect this pin to of hysteresis. When OV rises above its threshold, a 60mA an external resistive divider to set the desired VIN under- current sink pulls down on the GATE output. When OV voltage fault threshold. This input connects to an accu- falls back below 0.475V, and after a 32ms GATE turn-on rate, fast (1µs) comparator with a 0.5V falling threshold delay waiting period, the GATE charge pump is enabled. and 25mV of hysteresis. When UV falls below its thresh- The low leakage current on this input allows the use of old, a 60mA current sink pulls down on the GATE output. large valued resistors for the external resistive divider. When UV rises back above 0.525V, and after a 32ms GATE Connect to GND if unused. turn-on delay waiting period, the GATE charge pump is
RETRY:
Retry or Latch-Off Selection Input. Connect to enabled. The low leakage current on this input allows the ground to latch off the MOSFETs after a forward over- use of large valued resistors for the external resistive current fault. To turn the external MOSFETs back on, the divider. If unused and VIN is less than 80V, connect to SHDN pin must be toggled low then high. Connect RETRY VIN with a 510k resistor. to an external capacitor to configure a 5.5ms/nF delay
VIN:
Power Supply Input. Maximum protection range: before the MOSFETs automatically turn on again. Leave –40V to 100V. Operating range: 2.5V to 60V. This pin unconnected if unused. can be hot swapped and has a 2.2V UVLO.
SENSE:
Overcurrent Sense Input. Connect a current
VOUT:
Output Voltage Sense Input. Connect a current sense resistor between SENSE and VOUT. This input sense resistor between VOUT and SENSE. The GATE detects overcurrent faults in both directions: forward charge pump voltage is referenced to VOUT. It is used as at ΔVSENSE = 50mV, and reverse at ΔVSENSE = –50mV the charge pump input when VOUT is greater than approxi- (LTC4368-1 option) or ΔVSENSE = –3mV (LTC4368-2 mately 5V. The reverse current fault comparators require option). When an overcurrent fault is detected, a 60mA that VOUT rise above its 2.2V UVLO. VOUT cannot be hot swapped with supplies above 24V. Place at least 1µF from VOUT to GND. Rev A For more information www.analog.com 7 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Pin Functions Block Diagram Applications Information Related Parts Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Revision History Typical Application Related Parts