LTC4214-2CMS Linear Technology, LTC4214-2CMS Datasheet

IC CTRLR HOTSWAP NEGVOLT 10MSOP

LTC4214-2CMS

Manufacturer Part Number
LTC4214-2CMS
Description
IC CTRLR HOTSWAP NEGVOLT 10MSOP
Manufacturer
Linear Technology
Type
Hot-Swap Controllerr
Datasheet

Specifications of LTC4214-2CMS

Applications
General Purpose
Internal Switch(s)
No
Voltage - Supply
6 V ~ 16 V
Operating Temperature
0°C ~ 70°C
Mounting Type
Surface Mount
Package / Case
10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
Linear Misc Type
Negative Low Voltage
Family Name
LTC4214-2
Package Type
MSOP
Operating Supply Voltage (min)
-6V
Operating Supply Voltage (max)
-16V
Operating Temperature (min)
0C
Operating Temperature (max)
70C
Operating Temperature Classification
Commercial
Product Depth (mm)
3mm
Product Height (mm)
0.86mm
Product Length (mm)
3mm
Mounting
Surface Mount
Pin Count
10
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
LTC4214-2CMS
Manufacturer:
LT
Quantity:
10 000
FEATURES
APPLICATIO S
TYPICAL APPLICATIO
(SHORT PIN)
Allows Safe Board Insertion and Removal from a
Live Backplane
Controls Supplies from 0V to –16V
Adjustable Analog Current Limit With Circuit
Breaker Timer
Fast Response Time Limits Peak Fault Current
Adjustable Soft-Start Current Limit
Adjustable Timer with Drain Voltage Accelerated
Response
Adjustable Undervoltage/Overvoltage Protection
LTC4214-1: Latch Off After Fault
LTC4214-2: Automatic Retry After Fault
Available in the 10-Pin MSOP Package
Hot Board Insertion
Electronic Circuit Breaker
Negative Power Supply Control
Central Office Switching
High Availability Servers
Disk Arrays
Optical Networking/Switching
ECL
–5.2V
GND
3.3V
GND
32.4k
100nF
34k
1%
1%
10
– 5.2V/5A ECL Supply Hot Swap Controller
1nF
U
SMAJ7A
RESET
PUSH
5.6nF
U
9, 8
10
3
3.3nF
UV/OV
TIMER
SS
470
LTC4214-1
V
V
EE
IN
PWRGD
5
1
SENSE
DRAIN
GATE
2
7
6
4
2k
0.1 F
22
10
75k
10nF
C
100 F
LOAD
DESCRIPTIO
The LTC
allows a board to be safely inserted and removed from a
live backplane. Output current is controlled by three stages
of current limiting: a timed circuit breaker, active current
limiting and a fast feedforward path that limits peak
current under worst-case catastrophic fault conditions.
Adjustable undervoltage and overvoltage detectors dis-
connect the load whenever the input supply exceeds the
desired operating range. The LTC4214 controls negative
supplies ranging from near zero to –16V. A multifunction
timer delays initial start-up and controls the circuit breaker’s
response time. This response time is accelerated by
sensing excessive MOSFET drain voltage, keeping the
MOSFET within its safe operating area (SOA). An adjust-
able soft-start circuit controls MOSFET inrush current at
start-up. A power good status output can enable a power
module at start-up or disable it if the circuit breaker trips.
The LTC4214-1 latches off after a circuit breaker fault times
out. The LTC4214-2 provides automatic retry after a fault.
The LTC4214 is available in the 10-pin MSOP package.
Hot Swap is a trademark of Linear Technology Corporation.
BSS138
+
, LTC and LT are registered trademarks of Linear Technology Corporation.
4214 TA01
IRF7413
0.01
EN
GND
–5.2V
ECL
Negative Low Voltage
®
4214 negative voltage Hot Swap
Hot Swap Controllers
LTC4214-1/LTC4214-2
20mV/DIV
U
PWRGD
5V/DIV
5V/DIV
5V/DIV
SENSE
GATE
V
OUT
Start-Up Behavior
TM
controller
4214 TA02
421412f
1

Related parts for LTC4214-2CMS

LTC4214-2CMS Summary of contents

Page 1

... MOSFET inrush current at start-up. A power good status output can enable a power module at start-up or disable it if the circuit breaker trips. The LTC4214-1 latches off after a circuit breaker fault times out. The LTC4214-2 provides automatic retry after a fault. The LTC4214 is available in the 10-pin MSOP package. ...

Page 2

... SENSE EE GATE V – V GATE – V for PWRGD Status GATEH IN GATE (Before Gate Ramp-Up) UV Rising OV Rising ORDER PART NUMBER LTC4214-1CMS LTC4214-2CMS 10 TIMER 9 UV LTC4214-1IMS DRAIN LTC4214-2IMS 6 GATE MS PART MARKING = 160 C/W LTABH LTABK LTABJ LTABL MIN TYP MAX UNITS 6 16 ...

Page 3

... All voltages are referenced to V specified 1 1 1.2 1.0 0.8 0.6 0.4 0 (V) IN LTC4214-1/LTC4214-2 MIN TYP MAX –15 0.1 3 1.7 –5 = 2.2V TMR = 2.2V 28 TMR –40 –200 DRN 1.109 1.232 1.355 0.1 3.5 4.2 0.2 –30 –50 130 0.4 0.4 unless otherwise EE ...

Page 4

... LTC4214-1/LTC4214 TYPICAL PERFOR A CE CHARACTERISTICS otherwise specified. Undervoltage Lockout Hysteresis V vs Temperature LKH 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 –55 –35 – 105 25 65 TEMPERATURE ( C) 4214 G04 Fast Current Limit Voltage V vs Temperature FCL 300 V = 12V IN 275 250 225 200 ...

Page 5

... V vs Temperature UVHST 0. 12V IN 0.27 0.26 0.25 0.24 0.23 0.22 85 105 125 –55 –35 – TEMPERATURE ( C) LTC4214-1/LTC4214-2 All voltages are referenced to V Unless EE I (FCL, Sinking) GATE vs Temperature 400 V = 12V IN UV/OV = 2.5V 350 TIMER = 0.15V SENSE 300 V GATE 250 200 150 ...

Page 6

... LTC4214-1/LTC4214 TYPICAL PERFOR A CE CHARACTERISTICS otherwise specified Temperature OVHST 0. 12V IN 0.17 0.16 0.15 0.14 0.13 0.12 85 105 –55 –35 – TEMPERATURE ( C) 4214 G22 TIMER Threshold vs Temperature 4 12V IN 3.5 3.0 V TMRH 2.5 2.0 V TMRL 1.5 1.0 0.5 85 105 –55 –35 – TEMPERATURE ( C) ...

Page 7

... Temperature SS 160 V = 12V IN SS PIN FLOATING, V RAMPS FROM 0.2V TO 1.4V 150 SS 140 130 120 110 100 125 –55 –35 – 105 TEMPERATURE ( C) LTC4214-1/LTC4214-2 All voltages are referenced to V Unless DRN DRAIN 100 V = 12V 0.1 0.01 0.001 0.0001 0.00001 125 V (V) ...

Page 8

... LTC4214-1/LTC4214 CTIO S V (Pin 1): Positive Supply Input. Connect this pin to the IN positive side of the supply via a resistor. An internal undervoltage lockout (UVLO) circuit holds GATE low until the V pin is greater than V (5.1V), overriding UV and IN LKO OV high low and V IN TIMER starts an initial timing cycle before initiating a GATE ramp-up ...

Page 9

... C eventually integrates up to the V breaker trips, GATE quickly pulls low and PWRGD pulls high. The LTC4214-1 TIMER pin latches high with pull-up source. This latched fault is cleared by either pulling TIMER low with an external device or by pulling UV below 2V ...

Page 10

... LTC4214-1/LTC4214-2 W BLOCK DIAGRA – – 2.25V – TIMER 10 – 1. 69.35k 3.65k – 1.232V LOGIC FCL + V = 10mV ACL OS + – – 50mV – + – DRAIN PWRGD GATE 2.8V + – – – + 0.5V + 200mV + – – SENSE 4214 BD 421412f ...

Page 11

... The flow of current damages the connector pins and glitches the power bus, causing other boards in the system to reset. The LTC4214 is designed to turn on a circuit board supply in a controlled manner, allowing insertion or removal without glitches or connector damage. ...

Page 12

... LTC4214 will fully enhance the MOSFET. A second possibility is that the load current exceeds the soft-start current limit threshold this case the LTC4214 will ramp the output by sourcing soft-start limited current into the load capacitance. If the soft-start voltage is below 1.2V, the circuit breaker TIMER is held low ...

Page 13

... EE to function. This can be derived from GND and –12V of a –12V system or the 3.3V and –5. –5.2V system. The positive supply is connected that the LTC4214 can have a usable V short or other transient events when (V below 6V. INTERNAL UNDERVOLTAGE LOCKOUT (UVLO) A hysteretic comparator, UVLO, monitors V undervoltage ...

Page 14

... OUT the charging of C Intermittent overloads may exceed the 50mV threshold at is used at T SENSE, but, if their duration is sufficiently short, TIMER will not reach 3V and the LTC4214 will not shut the external ) fast charge; circuit breaker delay. DRN • reaches 3V (V ...

Page 15

... SENSE voltage is less than 50mV. Therefore, any intermit- tent overload with V < 3V and an aggregate duty cycle OUT of 12.5% or more will eventually trip the circuit breaker and shut down the LTC4214. Figure 4 shows the circuit breaker response time in seconds normalized for The asymmetric charging and discharging of DRN fair gauge of MOSFET heating ...

Page 16

... ACL amplifier to recover. SHORT-CIRCUIT OPERATION Circuit behavior arising from a load side low impedance short is shown in Figure 5 for the LTC4214. Initially, the current overshoots the fast current limit level of V 200mV (Trace 2) as the GATE pin works to bring V control (Trace 3) ...

Page 17

... Figure 5 Trace 1, can rob charge from output capacitors on adjacent cards. When the faulty card shuts down, current flows in to refresh the capacitors. If LTC4214s are used by the other cards, they respond by limiting the inrush current to a value of 70mV/R ...

Page 18

... MAX Consult MOSFET SOA curves: the IRF7413 can handle 3.2A at 20V for 3.5ms safe to use in this application. Calculate 22nF. SS FREQUENCY COMPENSATION C response. The LTC4214 typical frequency compensation network for SS SS the analog current limit loop is a series R connected given by: ...

Page 19

... MOSFET avalanche. SENSE RESISTOR CONSIDERATIONS For proper circuit breaker operation, Kelvin-sense PCB connections between the sense resistor and the LTC4214’s V and SENSE pins are strongly recommended. The EE drawing in Figure 7 illustrates the correct way of making connections between the LTC4214 and the sense resistor ...

Page 20

... In the example shown in Figure 9, power is delivered through long connector pins whereas the UV/OV divider makes contact through a short pin. This ensures the power , the fault TIMER cycle connections are firmly established before the LTC4214 is activated. At time point 1, the power pins make contact and V ramps through < ...

Page 21

... V (t) and soft-start limits the slew rate of the load GATEL ACL current. If the SENSE voltage (V V threshold at time point 7, the circuit breaker TIMER CB activates. The TIMER capacitor, C LTC4214-1/LTC4214 < 20 • V AND TIMER < TMRL , CHECK GATE < SENSE < V AND SS < 20 • V TMRL ...

Page 22

... W U Undervoltage Timing In Figure 10 when the UV pin drops below V (time point 1), the LTC4214 shuts down with TIMER, SS and GATE all pulling low. If current has been flowing, the SENSE pin voltage decreases to zero as GATE collapses. When UV recovers and clears V initial timer cycle begins followed by a start-up cycle. ...

Page 23

... TMRH • I DRN TMRL • ACL OS 20 • • GATE INITIAL TIMING START-UP LTC4214-1/LTC4214-2 (time point 1), an initial timing UVHI threshold. The initial timing cycle restarts, AND TIMER < TMRL , CHECK GATE < SENSE < V AND SS < 20 • V GATEL – GATEH V ACL V CB ...

Page 24

... LTC4214-1/LTC4214 APPLICATIO S I FOR ATIO Overvoltage Timing During normal operation, if the OV pin exceeds V shown at time point 1 of Figure 12, the TIMER and PWRGD status are unaffected. Nevertheless, SS and GATE pull down and the load is disconnected. At time point OVERSHOOTS OVHI OV V TIMER GATE ...

Page 25

... Momentary Circuit-Breaker Fault Figure 13. Circuit-Breaker Timing Behavior (All Waveforms are Referenced immediately and the LTC4214 shuts down. In Figure 13c, multiple momentary faults cause the TIMER capacitor to integrate and reach V the LTC4214 shuts down. During shutdown, the LTC4214-1 latches TIMER high with pull-up current source; the LTC4214-2 activates a shutdown cooling cycle ...

Page 26

... TIMER is used for reset. An initial timing cycle is generated if reset by the UV pin or the V TIMER SENSE DRAIN PWRGD Figure 14. Pushbutton Reset of LTC4214-1’s Latched Fault (All Waveforms are Referenced The duration of the TIMER reset pulse should be smaller than the time taken to reach 0. pin. With a single pole mechanical pushbutton switch, this may not be feasible ...

Page 27

... SENSE V OUT DRAIN PWRGD CB Figure 15. Shutdown Cooling Timing Behavior of LTC4214-2 (All Waveforms are Referenced and three 5 A charge phases in this shutdown cooling cycle spanning time points 2 and 3. At time point 3, the LTC4214 automatic retry occurs with a start-up cycle. , GATE pulls down Good thermal management techniques are highly recom- mended ...

Page 28

... LTC4214-1/LTC4214 APPLICATIO S I FOR ATIO Analog Current Limit and Fast Current Limit In Figure 16a, when SENSE exceeds V lated by the analog current limit amplifier loop. When SENSE drops below V , GATE is allowed to pull up. In ACL Figure 16b, when a severe fault occurs, SENSE exceeds ...

Page 29

... V ACL SENSE DRNCL V DRAIN DRNL PWRGD (17b) With External C SS LTC4214-1/LTC4214-2 (t) (Equation 7). At time ACL , at time point 7 and the circuit breaker CB (t). The current ACL can cause premature circuit breaker SS (t) may exceed the V potential during ACL CB values is SOA duration may ...

Page 30

... LTC4214-1/LTC4214 APPLICATIO S I FOR ATIO Power Limit Circuit Breaker Figure 18 shows the LTC4214 power limit circuit breaking application. The SENSE pin is modulated by the board supply voltage The zener voltage, V SUPPLY to be the same as the low supply operating voltage 10V. If the goal is to have the high supply ...

Page 31

... BSC 4.90 0.152 DETAIL “A” (.193 .006) 0.254 0 – 6 TYP 0.53 0.152 (.021 .006) DETAIL “A” SEATING PLANE 0.17 – 0.27 (.007 – .011) TYP LTC4214-1/LTC4214-2 0.497 0.076 (.0196 .003 REF 3.00 0.102 (.118 .004) (NOTE 0.86 1.10 (.034) ( ...

Page 32

... LTC4214-1/LTC4214-2 U TYPICAL APPLICATIO GND 470 100nF GND 1 (SHORT PIN 121k LTC4214 PWRGD 9 UV DRAIN R2 10 TIMER 32. SENSE 47nF 1nF 22nF –12V *M0C207 Z1:SMAJ15A Figure 19. – 12V/2A Hot Swap Controller RELATED PARTS PART NUMBER DESCRIPTION LTC1421 Two Channels, Hot Swap Controller LTC1642 ...

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