Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - hot swap controller Multi-purpose TQFN 20 Surface-mount

General Description

The MAX15068 offers ORing function and hot-swap

features for two input-supply-rail applications requiring the

safe insertion and removal of circuit line cards from a live

backplane. The device integrates dual ORing MOSFET

controllers, a single hot-swap controller, electronic circuit-

breaker protection, and power monitoring in a single

package. The device is designed to operate from 3.7V to

18V supply voltages.

The device regulates the forward voltage drop across the

ORing MOSFETs to ensure smooth current transfer from

one supply to the other without oscillation. The ORing

MOSFET turns on quickly to reduce the load voltage droop

during supply switchover. If the input supply fails or is short-

ed, a fast turn-off minimizes reverse-current transients.

The device implements a foldback current limit during hot-

swap startup in order to control inrush current, thereby

lowering di/dt and keeping the operation of the hot-swap

MOSFET under safe operating area (SOA). An internal

70ms timer starts counting when the device enters the

hot-swap startup phase. After the hot-swap startup cycle

is completed, on-chip comparators provide active current-

limit protection against short-circuit and overcurrent faults.

The load is disconnected from the input quickly in the

event of a fault condition.

The device provides current monitoring from 3A to 10A

= 12V, T

= +25°C with R

SENSE

= 3mΩ) with ±0.6%

accuracy. A voltage proportional to the input current

delivered to the system could be read directly at the

IPMON pin.

The device is factory-calibrated to deliver accurate

overcurrent protection with ±5% accuracy. During an

overcurrent-fault condition, the device enters an autoretry

mode. The device features an adjustable slew-rate control

during startup. Additional features include power-good

and fault-indicator outputs.

The MAX15068 is available in a 20-pin, (4mm x 5mm)

TQFN package and is specified from a -40°C to +125°C

operating temperature range.

Features and Benets

● 3.7V to 18V Operating Voltage Range (ORing and

Hot Swap)

● 4.8V to 18V Operating Voltage Range (Current

Monitor)

● Seamless Power Transition of Redundant Supplies

● Controls N-Channel MOSFETs

● < 0.5µs Turn-On and Reverse Turn-Off Time

● Current Monitoring (±0.6% Accuracy Typ)

● Programmable Slew-Rate Control

● Adjustable Current-Limit Fault Delay

● Programmable Circuit-Breaker Current Threshold

● Inrush Current Regulated at Startup with

Programmable SOA Control

● Programmable Undervoltage Lockout

● Small (4mm x 5mm) TQFN Package

Applications

● Baseband Station

● Redundant Power Supplies

● Supply Holdup

● Computer Systems and Servers

● Telecom Networks

● Storage Bridge Bay

Ordering Information appears at end of data sheet.

For related parts and recommended products to use with this part, refer

to www.maximintegrated.com/MAX15068.related.

MAX15068 Dual ORing, Single Hot-Swap Controller with

Accurate Current Monitoring

19-6872; Rev 0; 12/13

EVALUATION KIT AVAILABLE

Summary of content (17 pages)

PAGE 1
EVALUATION KIT AVAILABLE MAX15068 General Description Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring The MAX15068 offers ORing function and hot-swap features for two input-supply-rail applications requiring the safe insertion and removal of circuit line cards from a live backplane. The device integrates dual ORing MOSFET controllers, a single hot-swap controller, electronic circuitbreaker protection, and power monitoring in a single package.
PAGE 2
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Absolute Maximum Ratings IN1, IN2 to GND........................................................-1V to +24V PG, EN, FAULT, CSN to GND...............................-0.3V to +24V CSP to GND..............................................-0.3V to (VIN_ + 0.6V) VS to GND................................................................-0.3V to +6V ON, PC, IPMON, CB, CDLY to GND...........-0.3V to (VS + 0.3V) CSP to CSN..............
PAGE 3
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Electrical Characteristics (continued) (VIN1 = VIN2 = 12V, CIN1 = CIN2 = CVS = 1µF, TA = -40°C to +125°C. Typical values are at TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS Turn-Off Switch Resistance RDS_OFF VIN_- VCSP = -50mV, I = 50mA Turn-On Switch Resistance RDS_ON VIN_- VCSP_ = 120mV, I = 70mA ORing MOSFET Gate Drive (VOG_- VIN_) VOG_ 3.75V < VIN_< 18V MIN 6 TYP MAX UNITS 0.
PAGE 4
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Electrical Characteristics (continued) (VIN1 = VIN2 = 12V, CIN1 = CIN2 = CVS = 1µF, TA = -40°C to +125°C. Typical values are at TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER Maximum FB Voltage SYMBOL VFBMAX CONDITIONS VCSP - VOUT, at VCB = VCB_TH MIN TYP MAX UNITS 9 10 11 V 0.5 1.
PAGE 5
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Electrical Characteristics (continued) (VIN1 = VIN2 = 12V, CIN1 = CIN2 = CVS = 1µF, TA = -40°C to +125°C. Typical values are at TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER CB Input Open-Current Voltage SYMBOL VCB_OPEN CONDITIONS MIN Force ±4µA into unconnected CB pin; then measure voltage on the CB pin 1.0 0.
PAGE 6
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Typical Operating Characteristics (VIN1 = VIN2 = 12V, CIN1 = CIN2 = CVS = 1µF, RSENSE = 3mΩ, unless otherwise noted.) IN_ SUPPLY CURRENT vs. VOLTAGE VS LOAD REGULATION toc01 6 6 CHARGE-PUMP VOLTAGE vs. CURRENT toc02 VIN_ = 12V or 18V 0 0 3 6 9 VIN_ (V) 12 15 14 VCP_ - VIN_ (V) VIN_ = 3.7V 4 1 2 VIN_ = 3.
PAGE 7
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Typical Operating Characteristics (continued) (VIN1 = VIN2 = 12V, CIN1 = CIN2 = CVS = 1µF, RSENSE = 3mΩ, unless otherwise noted.) CB = Hi-Z CB = VS 1 0.1 0.01 CB = GND 0 50 100 150 200 250 40 30 20 10 0 300 SENSE VOLTAGE (VCSP - VCSN) (mV) GATE PULLUP CURRENT vs. TEMPERATURE toc12 15 10 5 0 -40 -15 10 35 60 85 6 8 10 -5 6 CURRENT (A) 8 10 12 85 110 125 toc14 VIN_ = 12V or 18V VIN_ = 4.
PAGE 8
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Typical Operating Characteristics (continued) (VIN1 = VIN2 = 12V, CIN1 = CIN2 = CVS = 1µF, RSENSE = 3mΩ, unless otherwise noted.) STARTUP WAVEFORM (VIN = 3.
PAGE 9
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Pin Configuration OG1 CP1 GATE OUT TOP VIEW 20 19 18 17 + 16 CB CSN 1 CSP 2 IN1 3 14 EN VS 4 13 CDLY GND 5 12 PC IN2 6 11 FAULT 15 ON MAX15068 7 8 9 10 OG2 CP2 IPMON PG EP TQFN (4mm × 5mm) Pin Description PIN NAME 1 CSN Input Current Sense Negative Input 2 CSP Input Current Sense Positive Input 3 IN1 Positive Supply 1 Input and MOSFET Gate Drive Return 4 VS Internal Regulator
PAGE 10
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Pin Description (continued) PIN NAME FUNCTION 10 PG Power Status Output. Open-drain output that is normally pulled high by a 10µA current source to a diode below VS. PG can be pulled above VS using an external pullup. PG pulls low when the MOSFET gate drive between GATE and OUT exceeds the gate-to-source voltage of 4.2V and VOUT is greater than 90% of VCSP. Leave PG unconnected if unused.
PAGE 11
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Functional Diagram CSP IN1 MAX15068 CSN IN2 VCB IPMON MAX15068 - CURRENT MONITOR - + 1.3 x VCB GATE + + GATE DRIVER - OUT 10µA VS CP1 VS CHARGE PUMP 2 CHARGE PUMP 3 VS + 10mV 10mV 1.2V VS OG2 + + + - - OG1 CP2 CHARGE PUMP 1 VS REFERENCE GENERATOR VS LDO REGULATOR UV2 10µA GATE 2.49V 10µA PG GATE_OK UV1 0.9 x VCSP 2.65V CIRCUIT BREAKER 1.
PAGE 12
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Detailed Description Startup When input voltage is applied to IN_, CSP comes up to one diode below the higher of IN1 or IN2. The internal LDO regulator powers VS from the higher of two inputs as well. When both VS and CSP reach their respective UVLO thresholds, the internal charge pumps (CP1 or CP2) for the ORing controller start operating.
PAGE 13
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring active current limit amplifier (ACL). The electronic circuit breaker turns off the hot-swap MOSFET with a 500µA current from GATE to OUT if the voltage across the sense resistor exceeds VCB_TH (ECB) for longer than the fault filter delay configured at the CDLY pin. Active current limiting begins when the sense voltage exceeds the ACL threshold VACL (ACL) (which is 1.3X the ECB threshold).
PAGE 14
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring The device turns off the output when VON falls below VUV_REF (1.22V - VON_HYS). An external resistive divider from CSP to ON and ground is used to set the undervoltage-lockout threshold to any desired level between VUVLO and 18V. Pulling the ON pin voltage below 0.6V resets the electronic circuit breaker. and the voltage at the OUT pin exceeds (0.9 x VCSP).
PAGE 15
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Figure 2 MD1 VMAIN 5.0V RSENSE 0.003Ω MD2 VAUX 5.0V CP1 53.6kΩ IN1 OG1 CP2 IN2 OG2 5.0V CSP CSN ON GATE OUT FAULT 20kΩ MAX15068 PG IPMON EN 20kΩ PC VS CB GND CDLY 69.8kΩ 20kΩ Figure 2. Plug-in Card IN1 Supply Controls the IN2 Supply Turn-On by the PC Pin www.maximintegrated.
PAGE 16
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Typical Application Circuit 12V RSENSE 0.003Ω 12V 12V CP1 137kΩ IN1 OG1 CP2 IN2 OG2 CSP CSN GATE ON OUT FAULT 20kΩ PG MAX15068 IPMON EN 20kΩ VS CB GND PC CDLY Ordering Information PART MAX15068ATP+ OPERATING RANGE FUNCTION TEMP RANGE PIN-PACKAGE 3.7V to 18V Autoretry, Current Monitor -40°C to +125°C 20 TQFN-EP* +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad.
PAGE 17
MAX15068 Dual ORing, Single Hot-Swap Controller with Accurate Current Monitoring Revision History REVISION NUMBER REVISION DATE 0 12/13 DESCRIPTION Initial release PAGES CHANGED — For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product.