ISL6160 Datasheet, PDF (3/11 Pages) Intersil Corporation – InfiniBand +12V Bulk and +5V Auxiliary Power Controller

ISL6160
Pin Descriptions
PIN NO. DESIGNATOR
FUNCTION
DESCRIPTION
1
ISET
Current Set
Connect to the low side of the current sense resistor through the current limiting set resistor.
This pin functions as the current regulation level voltage programming pin.
CR Vth = R_ISET X 20µA
2
ISEN
Current Sense
Connect to the more positive end of sense resistor to measure the voltage drop across this
resistor.
3
GATE
External FET Gate
Connect to the gate of the external N-Channel MOSFET. A capacitor from this node to
Drive Pin
ground sets the turn-on ramp. At turn-on this capacitor will be charged to VB +5V by a 10µA
current source.
4
VB_Ret
VB Chip Return
Bulk voltage ground
5
VA_Ret
VA Chip Return
Auxiliary voltage ground
6
VA_IN
VA Bias, Controlled VA_IN provides the chip with +5V bias voltage. At VA < 2.5V, VA control functionality is
Supply Input,
disabled, FAULT latch is cleared and floating and VA_OUT is held low.
Undervoltage Lock-Out
7
VA_ENn VA enable / disable Connected to VA_Ret through the IB connector, VA is asserted on module when VA_ENn
is low. Cycle to reset after latch-off. POR also resets latch.
8
NC
NC
9
VA_OUT Controlled Supply
Upon an OC condition VA_OUT is current limited to 1A. Current limit response time is within
Output
200µs. VA_Out will remain in current limit for ~10mS before being latched off.
10
VA_ FLTn Over Current Fault
Over current fault indicator. VA_FLTn floats and is disabled until VA >2.5V. This output is
Indicator
pulled low after the OC time-out period has expired and stays latched until module is
removed.
11
VB_IN
VB / Chip Supply
+12V Chip Supply.
12
CTIM
VB Current Regulation Connect a capacitor from this pin to ground. This capacitor determines the time delay
Period
between an overcurrent event and chip output shutdown (current limit time-out). The
duration of current limit time-out (in seconds) = 93kΩ x C_TIM (Farads).
13
DC-DC
VB_In Power Good Indicates that the VB voltage on ISEN pin is within specification and enables the DC-DC
ENABLE and DC-DC Enable converter. DC-DC ENABLE is driven by an open drain N-Channel MOSFET and is pulled
Signal
low when VB Secondary rail (V_ISEN) is not within specification.
14
VB_ON
VB Sequencer Enable VB_ON is used to control and reset the VB supply to IB module. VB is asserted on, when
Control Signal
VB_ON pin is driven high or is open. After a latch-off VB is reset by a low level signal applied
to this pin. This input has 20µA pull-up capability.
3