Electronic Components Datasheet Search |
|
LTC2924IGN Datasheet(PDF) 5 Page - Linear Technology |
|
LTC2924IGN Datasheet(HTML) 5 Page - Linear Technology |
5 / 20 page LTC2924 5 2924fa PI FU CTIO S IN1-IN4 (Pins 1, 2, 3, 4): Sequenced Power Supply Moni- tor Input. Connect this pin to an external resistive divider between each sequenced power supply and GND. During Power On sequencing, 0.61V (typ) at this pin indicates that the sequenced power supply (enabled with each of the OUT1-OUT4 pins) has reached the desired Power On sequence voltage. A hysteresis current (programmed by the HYS pin) is sourced out of each of the IN1-IN4 pins after the 0.61V threshold is detected. During the Power Off sequence, 0.61V at this pin indicates that the sequenced power supply has reached the desired Power Off voltage. The hysteresis current is removed after the 0.61V thresh- old is detected. OUT1-OUT4 (Pins 5, 6, 7, 8): Sequenced Power Supply Enable. Connect this pin to the shutdown pin or an external seriesN-channelMOSFETgateforeachpowersupplybeing sequenced. (A low at this pin means the sequenced power supply is commanded to turn off.) When disabled, each output is connected to GND with a resistance of <240Ω. When enabled, each output is connected to an internally generated charge pump supply (nominally VCC + 5V) via an internal 10µA (typ) current source. FAULT (Pin 9): Fault Pin. Pull this pin high with an external 10k resistor. The LTC2924 will pull this pin low if a fault condition is detected (see Applications Information for details). Pulling this pin low externally causes a simulta- neous unsequenced Power Off. DONE (Pin 10): Done Pin. Pull this pin high with an ex- ternal 10k resistor. This open-drain output pulls low at the completion of the Power-On sequence. At the end of the Power Off sequence, the LTC2924 floats this pin. For cascadingmultipleLTC2924s,seeApplicationInformation for connecting the DONE pin. VCC (Pin 11): LTC2924 Power Supply Input. All internal circuits are powered from this pin. VCC should be con- nected to a low noise power supply voltage and should be bypassed with at least a 0.1µF capacitor to the GND pin in close proximity to the LTC2924. PGT (Pin 12): Power Good Timer. The PGT pin sets the time allowed for a power supply to turn on after being enabled with the OUT1-OUT4 pins. Connecting a capacitor between this pin and ground programs a 200mS/µF dura- tion. The PGT pin is reset before each of the OUT1-OUT4 pins are asserted. If the voltage at the PGT pin reaches 1V, a fault condition is asserted. The PGT pin must be connected directly to ground to disable the power good timer function. GND (Pin 13): Ground. All internal circuits are returned to the GND pin. Connect this pin to the ground of the power supplies that are being sequenced. TMR (Pin 14): Timer. A capacitor connected between this pin and ground sets the time delay between a supply ready (IN1-IN4) signal and the enabling of the next power supply in the sequence (OUT1-OUT4), with a 200mS/µF duration. The TMR pin may be left floating if no delay is required between supplies being sequenced on or off. If an internal fault condition occurs, TMR will indicate so by going to VCC until the fault condition is cleared. Do not connect any other circuits to the TMR pin. HYS/CFG(Pin15):HysteresisCurrentSettingandCascade Configuration. Connecting a resistor between this pin and GND programs a 0.5/REXT (typ) hysteresis current which is sourced out of each IN and ON pin. When multiple LTC2924s are cascaded, the HYS/CFG pin is also used to configure the position of the first LTC2924. See Applica- tions Information for details. ON (Pin 16): On Pin. Commands the LTC2924 to sequence the power supplies up (Power On sequence) or down (Power Off sequence). Typically connected to a system controller. Hysteresis current is applied to this pin when above0.61V(typ).Thispinhasaprecision0.61Vthreshold and can be used to sense a nonsequenced power supply’s voltage to start the Power On sequence. See Applications Information for details. For cascading multiple LTC2924s, see Applications Information for connecting the ON pin. |
Similar Part No. - LTC2924IGN |
|
Similar Description - LTC2924IGN |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |