Document
LTC1643L/LTC1643L-1/LTC1643H PCI-Bus Hot Swap Controller
FEATURES
s s
DESCRIPTIO
s s
s s s s
Allows Safe Board Insertion and Removal from a Live PCI Slot Works on either a Motherboard (LTC1643H) or CompactPCITM Card (LTC1643L/LTC1643L-1) Controls –12V, 3.3V, 5V, 12V Supplies Programmable Foldback Current Limit with Circuit Breaker User-Programmable Supply Voltage Power-Up Rate High Side Drive for External N-Channels –12V and 12V On-Chip Switches Fault and Power-Good Outputs
U APPLICATIO S
s s
PCI-Based Servers CompactPCI Compliant Boards
, LTC and LT are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. CompactPCI is a trademark of PCI Industrial Computer Manufacturing Group.
The LTC®1643 is a Hot SwapTM controller that allows a board to be safely inserted and removed from a live PCI-Bus slot. Two external N-channel transistors control the 3.3V and 5V supplies while on-chip switches control the –12V and 12V supplies. All supply voltages can be ramped up at a programmable rate. An electronic circuit breaker protects all four supplies against overcurrent faults. The foldback current limit feature limits current spikes and power dissipation when shorts occur and allows boards with large capacitances to be powered up without tripping the circuit breaker. The PWRGD output indicates when all of the supply voltages are within tolerance and the FAULT output indicates an overcurrent condition. The ON(LTC1643H)/ON (LTC1643L/LTC1643L-1) pin is used to cycle the board power or reset the circuit breaker. The LTC1643L-1 has the ± 12V power good comparators disabled. The LTC1643 is available in a 16-pin narrow SSOP package.
TYPICAL APPLICATION
Hot Swappable PCI Supply
R1 0.007Ω Q1 IRF7413
R2 0.005Ω
Q2 IRF7413
R6 10Ω
SYSTEM POWER SUPPLY 9 3VIN GND 1 12VIN 2 VEEIN 5 ON 8 PCI POWER SYSTEM CONTROLLER RESET R3 10k R4 10k 6 10
R5 10Ω 11 3 13 12 5VSENSE 14 5VOUT
R7 100Ω C1 0.047µF
3VSENSE GATE
3VOUT 5VIN
12VOUT LTC1643H VEEOUT
FAULT TIMER
7
PWRGD
U
5V 5A 3.3V 7.6A GND 16 15 4 C2 0.1µF 12V 500mA –12V 100mA LOGIC RESET
1643 TA01
U
1
LTC1643L/LTC1643L-1/LTC1643H
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PACKAGE/ORDER INFORMATION
TOP VIEW 12VIN 1 VEEIN 2 3VOUT 3 TIMER 4 ON/ON* 5 FAULT 6 PWRGD 7 GND 8 16 12VOUT 15 VEEOUT 14 5VOUT 13 5VIN 12 5VSENSE 11 GATE 10 3VSENSE 9 3VIN
Supply Voltages 12VIN ................................................................ 13.2V VEEIN .............................................................. –13.2V Input Voltage (Pin 5) ................ – 0.3V to (12VIN + 0.3V) Output Voltages (Pins 6, 7) ...... – 0.3V to (12VIN + 0.3V) Analog Voltages (Pins 3, 4, 9, 10 to 14) ........ – 0.3V to (12VIN + 0.3V) VEEOUT ............................................ –13.2V to + 0.3V 12VOUT .............................................. – 0.3V to 13.2V Operating Temperature Range Commercial ............................................. 0°C to 70°C Industrial ........................................... – 40°C to 85°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART NUMBER LTC1643HCGN LTC1643LCGN LTC1643L-1CGN LTC1643HIGN LTC1643LIGN
GN PACKAGE 16-LEAD NARROW PLASTIC SSOP * ON FOR LTC1643H, ON FOR LTC1643L
TJMAX = 150°C, θJA = 135°C/ W
Consult factory for Military grade parts.
DC ELECTRICAL CHARACTERISTICS
SYMBOL IDD VLKO PARAMETER V12VIN Supply Current Undervoltage Lockout CONDITIONS
The q denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C. V12VIN = 12V, VEE = – 12V, V3VIN = 3.3V, V5VIN = 5V. (Note 2)
MIN
q q q q q q q q
TYP 3.5 9.5 2.5 2.5 7.5 53 7.5 53 14.6 – 50 200 10 100 250 250 120
MAX 8 10.8 2.75 2.75 12 65 12 65 – 100 20 200 600 750 250 500 1500 215 800 11.4 11.4 – 10.8 – 10.8
UNITS mA V V V mV mV mV mV µs µA µA mA mV mV mV mV mA mA mA mA °C V V V V
ON = 3V, ON = GND 12VIN 3VIN 5VIN VFB = (V5VIN – V5VSENSE), V5VOUT = 0V VFB = (V5VIN – V5VSENSE), V5VOUT > 4V VFB = (V3VIN – V3VSENSE), V3VOUT = 0V VFB = (V3VIN – V3VSENSE), V3VOUT > 2V Charge Pump On, VGATE = GND, FAULT = High Charge Pump Off, VGATE = 5V, FAULT = High Charge Pump Off, VGATE = 2V, FAULT = Low (V12VIN – VGATE) (V12VIN – V12VOUT), I12VOUT = 500mA C Grade I Grade (VEEOUT – VEEIN), IVEEIN = 100mA 12VIN = 12V, 12VOUT = 0V 12VIN, 12VOUT = 12V VEEIN = –12V, VEEOUT = 0V VEEIN, VEEOUT = – 12V V12VOUT LTC1643H/LTC1643L Only VEEOUT LTC1643H/LTC1643L Only C Grade I Grade C Grade I Grade
7 2.25 2.25 4 40 4 40 – 20 3
VFB
Foldback Current Limit Voltage
tCB ICP
Circuit Breaker Trip Filter Time GATE Pin Output Current
q q
∆VGATE VDROP
External Gate Voltage Internal Switch Voltage Drop
q q q q q q q
ICL
Current Foldback
50 525 100 225 10.8 10.4 – 10.2 – 10.0
250 850 160 450 150 11.1 11.1 – 10.5 – 10.5
TTS VTH
Thermal Shutdown Temperature Power-Good Threshold Voltage
q q q q
2
U
W
U
U
W W
W
LTC1643L/LTC164.