Rainbow Electronics MAX5970 User Manual

19-5128; Rev 0; 1/10

EVALUATION KIT

AVAILABLE

0V to 16V, Dual Hot-Swap Controller with 10-Bit

Current and Voltage Monitor and 4 LED Drivers

General Description

The MAX5970 dual hot-swap controller provides complete protection for systems with two supply voltages from 0V to +16V. The MAX5970 includes four programmable LED outputs. The two hot-swap channels can be configured to operate as independent hot-swap controllers, or as a pair operating together so that both channels shut down if either channel experiences a fault.

The MAX5970 provides two programmable levels of overcurrent circuit-breaker protection: a fast-trip threshold for a fast turn-off, and a lower slow-trip threshold for a delayed turn-off. The maximum overcurrent circuitbreaker threshold range is set independently for each channel with a trilevel logic input IRNG_, or by programming though the I2C interface.

The MAX5970 is an advanced hot-swap controller that monitors voltage and current with an internal 10-bit ADC which is continuously multiplexed to convert the output voltage and current of both hot-swap channels at 10ksps. Each 10-bit sample is stored in an internal circular buffer so that 50 past samples of each signal can be read back through the I2C interface at any time or after a fault condition.

The device includes five user-programmable digital comparators per hot-swap channel to implement overcurrent warning and two levels of overvoltage/undervoltage detection. When any of the measured values violates the programmable limits, an external ALERT output is asserted. In addition to the ALERT signal, the MAX5970 can be programmed to deassert the power-good signal and/or turn off the external MOSFET.

The MAX5970 features four I/Os that can be independently configured as general-purpose inputs/outputs (GPIOs) or as open-drain LED drivers with programmable blinking. These four I/Os can be configured for any mix of LED driver or GPIO function.

The MAX5970 is available in a 36-pin thin QFN-EP package and operates over the -40NC to +85NC extended temperature range.

Features

S Two Independent Hot-Swap Controllers Operate

from 0V to +16V

S 10-Bit ADC Monitors Voltage and Current of Each

Channel

S Circular Buffers Store 5ms of Current and Voltage

Measurements

S Two Independent Internal Charge Pumps

Generate n-Channel MOSFET Gate Drives

S Internal 500mA Gate Pulldown Current for Fast

Shutdown

S VariableSpeed/BiLevel™ Circuit-Breaker

Protection

S Independent Precision-Voltage Enable Inputs

S Alert Output Indicates Fault and Warning

Conditions

S Independent Power-Good Outputs

S Independent Fault Outputs

S Four Open-Drain Outputs Sink 25mA to Directly

Drive LEDs

S Programmable LED Flashing Function

S Autoretry or Latched Fault Management

S 400kHz I

S Small 6mm x 6mm, 36-Pin TQFN-EP Package

2

C Interface

Applications

Single PCI ExpressM Hot-Plug Slot

Blade Servers

Disk Drives/DASD/Storage Systems

Soft-Switch for ASICs, FPGAs, and Microcontrollers with Independent Core and I/O Voltages

Ordering Information

PART TEMP RANGE PIN-PACKAGE

MAX5970ETX+

-40NC to +85NC

36 TQFN-EP*

MAX5970

+Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad.

VariableSpeed/BiLevel is a trademark of Maxim Integrated Products, Inc. PCI Express is a registered trademark of PCI-SIG Corp.

_______________________________________________________________ Maxim Integrated Products 1

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

0V to 16V, Dual Hot-Swap Controller with 10-Bit Current and Voltage Monitor and 4 LED Drivers

ABSOLUTE MAXIMUM RATINGS

IN, SENSE_, MON_, GATE_ to AGND ..................-0.3V to +30V

LED_ to AGND ......................................................-0.3V to +16V

ON_, SDA, SCL to AGND ........................................-0.3V to +6V

REG, DREG, IRNG_, MODE, PROT, A_,

PG_, ALERT, FAULT_ to AGND ................................-0.3V to +4V

REG to DREG .......................................................-0.3V to +0.3V

RETRY, HWEN, POL to AGND ................-0.3V to (V

GATE1 to MON1, GATE2 to MON2 ........................-0.3V to +6V

MAX5970

GND_, DGND to AGND .......................................-0.3V to +0.3V

SDA, ALERT Current ....................................... -20mA to +50mA

LED_ Current ................................................. -20mA to +100mA

Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-

layer board. For detailed information on package thermal consideration, refer to www.maxim-ic.com/thermal-tutorial.

**As per JEDEC51 Standard (Multilayer Board)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

REG

+ 0.3V)

ELECTRICAL CHARACTERISTICS

(VIN = 2.7V to 16V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VIN = 3.3V and TA = +25NC.) (Note 2)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Supply Input-Voltage Range V Hot-Swap Voltage Range 0 16 V Supply Current I Internal LDO Output Voltage REG I Undervoltage Lockout UVLO VIN rising 2.7 V

Undervoltage Lockout Hysteresis

CURRENT-MONITORING FUNCTION

MON_, SENSE_ Input-Voltage Range

SENSE_ Input Current V MON_ Input Current V

Current Measurement LSB Voltage

Current Measurement Error (25mV Range)

Current Measurement Error (50mV Range)

UVLO

IN

= 0 to 5mA, VIN = 2.7V to 16V 2.49 2.53 2.6 V

REG

HYS

, V

SENSE_

25mV range 24.34 50mV range 48.39 100mV range 96.77

V

MON_

V

MON_

to 16V

V

MON_

V

MON_

to 16V

MON_

, V

MON_

= 0V

= 2.5V

= 0V

= 2.5V

GATE_, MON_, GND_ Current .........................................750mA

All Other Pins Input/Output Current ...................................20mA

Continuous Power Dissipation (TA = +70NC) 36-Pin, 6mm x 6mm TQFN

(derate 35.7mW/°C above +70°C).......................... 2857mW**

Junction-to-Ambient Thermal Resistance (BJA) (Note 1) ..28NC/W

Operating Temperature Range .......................... -40NC to +85NC

Junction Temperature .....................................................+150NC

Storage Temperature Range ............................ -65NC to +150NC

Lead Temperature (soldering, 10s) ................................+300NC

2.7 16 V

2.5 4 mA

100 mV

0 16 V

= 16V 32 75 = 16V 180 280

V V V V V V V V

SENSE_

- V

= 5mV -6.57 +6.22

MON_

= 20mV -6.71 +6.82

MON_

= 5mV -9.71 +8.92

MON_

= 20mV -10.24 +9.36

MON_

= 10mV -4.24 +3.78

MON_

= 40mV -4.53 +5.36

MON_

= 10mV -4.50 +4.00

MON_

= 40mV -4.20 +4.50

MON_

FA FA

FV

% FS

2 ______________________________________________________________________________________

0V to 16V, Dual Hot-Swap Controller with 10-Bit

Current and Voltage Monitor and 4 LED Drivers

ELECTRICAL CHARACTERISTICS (continued)

(VIN = 2.7V to 16V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VIN = 3.3V and TA = +25NC.) (Note 2)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Current Measurement Error (100mV Range)

Fast Current-Limit Threshold Error (25mV Range)

Fast Current-Limit Threshold Error (50mV Range)

Fast Current-Limit Threshold Error (100mV Range)

Slow Current-Limit Threshold Error (25mV Range)

Slow Current-Limit Threshold Error (50mV Range)

Slow Current-Limit Threshold Error (100mV Range)

Fast Circuit-Breaker Response Time

t

FCB

V

= 0V

MON_

V

= 2.5V

MON_

to 16V

V

= 0V

MON_

V

= 2.5V

MON_

to 16V

V

= 0V

MON_

V

= 2.5V

MON_

to 16V

V

= 0V

MON_

V

= 2.5V

MON_

to 16V

V

= 0V

MON_

V

= 2.5V

MON_

to 16V

V

= 0V

MON_

V

= 2.5V

MON_

to 16V

V

= 0V

MON_

V

= 2.5V

MON_

to 16V

Overdrive = 10% of current-sense range 2

V V V V Circuit breaker, DAC = 102 -2.106 +0.888 Circuit breaker, DAC = 255 -2.986 +0.641 Circuit breaker, DAC = 102 -3.000 +1.000 Circuit breaker, DAC = 255 -3.500 +1.500 Circuit breaker, DAC = 102 -3.1188 +0.926 Circuit breaker, DAC = 255 -4.873 +0.3421 Circuit breaker, DAC = 102 -3.2668 +0.9228 Circuit breaker, DAC = 255 -4.7 +1.0212 Circuit breaker, DAC = 102 -4.7987 +1.1812 Circuit breaker, DAC = 255 -8.9236 +0.202 Circuit breaker, DAC = 102 -4.9991 +0.6374 Circuit breaker, DAC = 255 -8.262 +1 Circuit breaker, DAC = 102 -1.7965 +1.5496 Circuit breaker, DAC = 255 -1.86 +1.5916 Circuit breaker, DAC = 102 -2.149 +1.9868 Circuit breaker, DAC = 255 -2.2285 +1.9982 Circuit breaker, DAC = 102 -2.3992 +1.8723 Circuit breaker, DAC = 255 -2.5146 +2.1711 Circuit breaker, DAC = 102 -2.4716 +2.181 Circuit breaker, DAC = 255 -2.7421 +2.1152 Circuit breaker, DAC = 102 -3.3412 +2.989 Circuit breaker, DAC = 255 -3.8762 +3.6789 Circuit breaker, DAC = 102 -3.2084 +2.7798 Circuit breaker, DAC = 255 -3.8424 +2.6483

SENSE_

- V

= 20mV -2.70 +2.43

MON_

= 80mV -3.63 +4.56

MON_

= 20mV -3.14 +3.19

MON_

= 80mV -3.80 +3.93

MON_

% FS

mV

Fs

MAX5970

Slow Current-Limit Response Time

THREE-STATE INPUTS

A_, IRNG_, MODE, PROT Low Current

A_, IRNG_, MODE, PROT T High Current

A_, IRNG_, MODE, PROT Open Current

_______________________________________________________________________________________ 3

t

SCB

I

IN_LOW

I

IN_HIGH

I

FLOAT

Overdrive = 4% of current-sense range 2.4

Overdrive = 8% of current-sense range 1.2 Overdrive = 16% of current-sense range 0.6

Input voltage = 0.4V -40

Input voltage = V

Maximum source/sink current for open state -4 +4

- 0.2V 40

REG

ms

FA

0V to 16V, Dual Hot-Swap Controller with 10-Bit Current and Voltage Monitor and 4 LED Drivers

ELECTRICAL CHARACTERISTICS (continued)

(VIN = 2.7V to 16V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VIN = 3.3V and TA = +25NC.) (Note 2)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

A_, IRNG_, MODE, PROT Low Voltage

A_, IRNG_, MODE, PROT High Voltage

MAX5970

TWO-STATE INPUTS

ON_ Input Voltage V ON_ Input Hysteresis V ON_ Input Current -100 +100 nA

TIMING

MON_ to PG_ Delay

CHARGE PUMP (GATE_)

Charge-Pump Output Voltage Relative to MON_, I

Charge-Pump Output Source Current

GATE_ Discharge Current I

OUTPUT (FAULT_, PG_, ALERT)

Output-Voltage Low I Output Leakage Current 1

LED INPUT/OUTPUT

LED_ Input Threshold Low Level V LED_ Input Threshold High Level V LED_ Output Low V

LED_ Input Leakage Current (Open Drain)

LED_ Weak Pullup Current I

ADC PERFORMANCE

Resolution 10 Bits Maximum Integral Nonlinearity INL 1 LSB

ADC Total Monitoring Cycle Time

MON_ LSB Voltage

MON_ Code 000H to 001H Transition Voltage

ON_

ON_HYS

I

G(UP)

G(DN)VGATE_

I

GPIO_IXVLED_

PU_WEAKVLED_

Relative to AGND 0.4 V

Relative to REG -0.24 V

0.582 0.592 0.602 V 4 %

50

Register configurable (see Tables 31a and 31b)

= 0 4.5 5.1 5.5 V

GATE

4 5 6

- V

= 3.2mA 0.2 V

SINK

IL

IH

I

OL

= 25mA 0.7 V

LED_

= 16V -1 +1

= VIN - 0.65V 2

Two voltage and two current-sense conversion 95 100 110

16V range 15.23 15.49 15.69 8V range 7.655 7.743 7.811 4V range 3.811 3.875 3.933 2V range 1.899 1.934 1.966 16V range 10 25 41 8V range 4.7 12 21 4V range 2 6 12 2V range 0.5 3 5.5

= 2V 500 mA

MON_

1.4 V

100 200 400

0.4 V

ms

FA

Fs

mV

4 ______________________________________________________________________________________

0V to 16V, Dual Hot-Swap Controller with 10-Bit

SUPPLY CURRENT (mA)

Current and Voltage Monitor and 4 LED Drivers

ELECTRICAL CHARACTERISTICS (continued)

(VIN = 2.7V to 16V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VIN = 3.3V and TA = +25NC.) (Note 2)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

I2C iNTERFACE

Serial-Clock Frequency f

Bus Free Time Between STOP and START Condition

START Condition Setup Time t START Condition Hold Time t STOP Condition Setup Time t Clock High Period t Clock Low Period t Data Setup Time t

Data Hold Time t

Output Fall Time t

Pulse Width of Spike Suppressed

SDA, SCL Input High Voltage V SDA, SCL Input Low Voltage V SDA, SCL Input Hysteresis V

SCL

t

BUF

SU:STA

HD:STA

SU:STO

HIGH

LOW

SU:DAT

HD:DAT

OF

t

SP

IH

IL

HYST

1.3

0.6

1.3

100 ns

Transmit 100

Receive 300 900

C

= 10pF to 400pF 250 ns

BUS

50 ns

1.8 V

0.22 V SDA, SCL Input Current -1 +1 SDA, SCL Input Capacitance 15 pF SDA Output Voltage V

OLISINK

= 4mA 0.4 V

Note 2: All devices are 100% production tested at TA = +25NC. Limits over the temperature range are guaranteed by design.

400 kHz

Fs

Fs Fs Fs Fs Fs

ns

0.8 V

FA

MAX5970

Typical Operating Characteristics

(VIN = 3.3V, TA = +25NC, unless otherwise noted.)

SUPPLY CURRENT

vs. SUPPLY VOLTAGE

2.50

2.45

BOTH CHANNELS ON

2.40

2.35

2.30

BOTH CHANNELS OFF

0 16

SUPPLY VOLTAGE (V)

_______________________________________________________________________________________ 5

SUPPLY CURRENT vs. TEMPERATURE

3.0

2.9

MAX5970 toc01

2.8

2.7

2.6

2.5

2.4

2.3

SUPPLY CURRENT (mA)

2.2

2.1

1412108642

2.0

-40 85 TEMPERATURE (°C)

603510-15

MAX5970 toc02

GATE-DRIVE VOLTAGE (V)

GATE-DRIVE VOLTAGE vs. V

5.20 V

REFERRED TO MON_

GATE

5.15

5.10

5.05

5.00

4.95

4.90

4.85

4.80

0 16

V

(V)

MON_

14122 4 6 8 10

MAX5970 toc03

0V to 16V, Dual Hot-Swap Controller with 10-Bit Current and Voltage Monitor and 4 LED Drivers

Typical Operating Characteristics (continued)

(VIN = 3.3V, TA = +25NC, unless otherwise noted.)

GATE_ DRIVE VOLTAGE vs. V

5.10

MAX5970

5.05

) (V)

5.00

MON_

- V

4.95

GATE_

(V

4.90

4.85

V

= 3.3V

MON_

V

= 12V

MON_

0 16

SLOW COMPARATOR TURN-OFF TIME

vs. VOLTAGE OVERDRIVE

3.00

2.50

2.00

1.50

1.00

TURN-OFF TIME (ms)

0.50

0

0 5

(V

- V

SENSE

VIN (V)

25mV SENSE RANGE, DAC = 191, V

MON_

) - V

TH,ST

(mV)

IN

1412108642

= 9.36mv

4321

10

9

MAX5970 toc04

8

7

6

5

4

3

GATE_ DRIVE CURRENT (µA)

2

1

0

0 5.0

SLOW COMPARATOR THRESHOLD

VOLTAGE ERROR vs. TEMPERATURE

10

MAX5970 toc07

8

6

4

2

0

100mV SENSE RANGE

-2

-4

-6

THRESHOLD VOLTAGE ERROR (%)

-8

-10

-40 85

GATE_ DRIVE CURRENT

vs. (V

25mV SENSE RANGE

- V

GATE_

MON_

(V

- V

GATE_

MON_

50mV SENSE RANGE

TEMPERATURE (°C)

) (V)

)

1.0

0.9

MAX5970 toc05

0.8

0.7

0.6

0.5

0.4

0.3

0.2

GATE_ DRIVE DISCHARGE CURRENT (A)

0.1

4.54.03.0 3.51.0 1.5 2.0 2.50.5

0

0 5.0

vs. (V

(V

GATE_

- V

)

MON_

MAX5970 toc06

4.54.03.0 3.51.0 1.5 2.0 2.50.5

- V

) (V)

MON_

ON_ THRESHOLD VOLTAGE

vs. TEMPERATURE

0.60

GATE_ DRIVE DISCHARGE CURRENT

0.59

MAX5970 toc08

0.58

0.57

0.56

0.55

0.54

0.53

ON_ THRESHOLD VOLTAGE (V)

0.52

0.51

603510-15

0.50

-40 85

RISING

FALLING

TEMPERATURE (°C)

MAX5970 toc09

603510-15

STARTUP WAVEFORM

10ms/div

MAX5970 toc10

V

ON_

2V/div

V

GATE_

5V/div

V

MON_

5V/div

V

PG_

5V/div

I

LOAD

2A/div

I

LOAD

2A/div

V

GATE_

10V/div

V

MON_

10V/div

V

FAULT

5V/div

(SLOW-COMPARATOR FAULT)

400µs/div

MAX5970 toc11

6 ______________________________________________________________________________________

TURN-OFF WAVEFORM

0V to 16V, Dual Hot-Swap Controller with 10-Bit

Current and Voltage Monitor and 4 LED Drivers

Typical Operating Characteristics (continued)

(VIN = 3.3V, TA = +25NC, unless otherwise noted.)

TURN-OFF WAVEFORM

(FAST COMPARATOR

I

LOAD

5A/div

V

GATE_

10V/div

V

MON_

10V/div

FAULT_

5V/div

FAULT/SHORT-CIRCUIT RESPONSE)

100µs/div

MAX5970 toc12

16

14

12

10

VOLTAGE BUFFER (V)

VOLTAGE BUFFER vs. TIME

CIRCULAR BUFFER CONTENT AT SLOW-TRIP FAULT MON = 16V, CURRENT SENSE = 50mV

8

6

4

2

0

-2.5 2.5 TIME (ms)

2.01.5-2.0 -1.5 -1.0 0 0.5-0.5 1.0

MAX5970 toc13

I

LOAD

2A/div

V

GATE_

10V/div

V

MON_

10V/div

V

FAULT

5V/div

SLOW-COMPARATOR FAULT EVENT

400µs/div

MAX5970 toc14

MAX5970

VOLTAGE ADC ACCURACY

vs. MON_ VOLTAGE

1.0 MON_ VOLTAGE RANGE = 4V

0.8

0.6

0.4

0.2

0

-0.2

-0.4

VOLTGE ADC ACCURACY (%FS)

-0.6

-0.8

-1.0 0 4.0

V

(V)

MON_

VOLTAGE BUFFER vs. TIME

0.5 VOLTAGE DATA AT SHORT CIRCUIT ON

0.4 POWER-UP DEFAULT SETTING V

0.3

0.2

0.1

0

-0.1

VOLTAGE BUFFER (V)

-0.2

-0.3

-0.4

-0.5

-2.5 2.5 TIME (ms)

MON

3.53.02.0 2.51.0 1.50.5

= 16V

CURRENT ADC ACCURACY

CURRENT BUFFER vs. TIME

DEFAULT SETTING

9

8

7

6

5

4

3

2

1

0

-2.5 2.5 TIME (ms)

2.01.50.5 1.0-1.5 -1.0 -0.5 0-2.0

MAX5970 toc17

5

4

MAX5970 toc15

3

2

1

0

-1

-2

-3

CURRENT ADC ACCURACY (% FS)

-4

-5 0 25.0

vs. (V

(V

SENSE_

- V

MON_

) (mV)

)

10

MAX5970 toc16

CURRENT BUFFER (A)

22.520.015.0 17.55.0 7.5 10.0 12.52.5

INPUT LEAKAGE CURRENT

STARTUP INTO SHORT LOAD

V

MAX5970 toc18

ON_

5V/div

I

LOAD

5A/div

V

GATE

2V/div

V

MON_

1V/div

FAULT_

5V/div

2.01.50.5 1.0-1.5 -1.0 -0.5 0-2.0

4ms/div

MAX5970 toc19

200

180

160

140

120

100

80

60

INPUT LEAKAGE CURRENT (µA)

40

20

0

0 16

vs. MON_ VOLTAGE

I

MON_

I

SENSE_

V

(V)

MON_

MAX5970 toc20

14128 104 62

_______________________________________________________________________________________ 7

0V to 16V, Dual Hot-Swap Controller with 10-Bit Current and Voltage Monitor and 4 LED Drivers

Pin Configuration

TOP VIEW

MON2

SENSE2

GATE2

GND2

LED3

LED4

MODE

RETRY

ON2

363534333231302928

MAX5970

1

IRNG2

2

IRNG1

3

IN

4

AGND

5

REG

BIAS

6

A1

7

A0

8

PROT

9

*EP = EXPOSED PAD.

MAX5970

EP*

101112131415161718

POL

LED1

LED2

GND1

MON1

GATE1

SENSE1

TQFN

DREG

ON1

27

DGND

26

HWEN

25

PG2 PG1

24

ALERT

23

SCL

22

SDA

21

FAULT2

20

FAULT1

19

Pin Description

PIN NAME FUNCTION

1 IRNG2

2 IRNG1

3 IN 4 AGND Analog Ground. Connect all GND_ and DGND to AGND externally using a star connection.

5 REG

6 BIAS For normal operation, connect BIAS to REG. 7 A1 Three-State I2C Address Input 1 8 A0 Three-State I2C Address Input 0

9 PROT

10 SENSE1

11 MON1 Channel 1 Voltage Monitoring Input 12 GATE1 Channel 1 Gate-Drive Output. Connect to the gate of an external n-channel MOSFET.

13 GND1

Channel 2 Three-State Current-Sense Range Selection Input. Set the circuit-breaker threshold range by connecting to DGND, DREG, or leave unconnected.

Channel 1 Three-State Current-Sense Range Selection Input. Set the circuit-breaker threshold range by connecting to DGND, DREG, or leave unconnected.

Power-Supply Input. Connect to a voltage from 2.7V to 16V. Bypass to AGND with a 1FF capacitor.

Internal Regulator Output. Bypass to ground with a 1FF capacitor. Connect only to DREG. Do not use to power external circuitry.

Protection Behavior Input. Three-state input sets one of three different response options for undervoltage and overvoltage events.

Channel 1 Current-Sense Input. Connect SENSE1 to the source of an external MOSFET and to one end of R

SENSE1

.

Channel 1 Gate Discharge Current Ground Return. Connect all GND_ and DGND to AGND externally using a star connection.

8 ______________________________________________________________________________________

0V to 16V, Dual Hot-Swap Controller with 10-Bit

Current and Voltage Monitor and 4 LED Drivers

Pin Description (continued)

PIN NAME FUNCTION

14 LED1 LED Driver 1 15 LED2 LED Driver 2

16 POL

17 DREG

18 ON1 Channel 1 Precision Turn-On Input 19 20 21 SDA I2C Serial-Data Input/Output 22 SCL I2C Serial-Clock Input 23 24 PG1 Channel 1 Open-Drain Power-Good Output 25 PG2 Channel 2 Open-Drain Power-Good Output

26 HWEN

27 DGND Digital Ground. Connect all GND_ and DGND to AGND externally using a star connection. 28 ON2 Channel 2 Precision Turn-On Input

29 RETRY

30 MODE

31 LED4 LED Driver 4 32 LED3 LED Driver 3

33 GND2

34 GATE2 Channel 2 Gate-Drive Output. Connect to gate of an external n-channel MOSFET. 35 MON2 Channel 2 Voltage Monitoring Input

36 SENSE2

— EP Exposed Pad. EP is internally grounded. Connect externally to ground plane using a star connection.

FAULT1 Channel 1 Active-Low Open-Drain Fault Output. FAULT1 goes low if an overcurrent occurs on channel 1. FAULT2 Channel 2 Active-Low Open-Drain Fault Output. FAULT2 goes low if an overcurrent occurs on channel 2.

ALERT Open-Drain Alert Output. ALERT goes low during a fault to notify the system of an impending failure.

Polarity Select Input. Connect to DREG for active-high power-good outputs (PG_). Connect to GND for active-low power-good outputs.

Logic Power-Supply Input. Connect to REG externally through a 10I resistor and to DGND with a 1FF ceramic capacitor.

Hardware Enable Input. Connect to DREG or DGND. State is read upon power-up as VIN crosses the UVLO threshold and sets enable register bits with this value. After UVLO, this input becomes inactive until power is cycled.

Autoretry Fault Management Input. Connect to DREG to enable autoretry operation. Connect to DGND to enable latched-off operation.

Hot-Swap Two-State Mode Select Input. Connect MODE to DGND, DREG or leave it unconnected to operate the hot-swap channels independently or as a pair.

Channel 2 Gate Discharge Current Ground Return. Connect all GND_ and DGND to AGND externally using a star connection.

Channel 2 Current-Sense Input. Connect SENSE2 to the source of an external MOSFET and to one end of R

SENSE2

.

MAX5970

_______________________________________________________________________________________ 9

0V to 16V, Dual Hot-Swap Controller with 10-Bit Current and Voltage Monitor and 4 LED Drivers

Typical Application Circuit

V

CC

MAX5970

V+

R

LED2

TO

R

LED1

LOAD

R

SENSE1

I/O

(2)

FAULT_

INT

ALERT

µP

V

4.7kI

ON2

CC

V

IN2

R1

ON2

R2

ON2

Q2

V+

R

SENSE2

TO

LOAD

R

LED3

R

LED4

I/O

(2)

PG_

SDA

SCLK

SCL

GATE2

SENSE2

MON2

LED3

LED4

V

CC

R

V

IN1

Q1

VIN = 2.7V to 16V

R1

ON1

R2

ON1

IN

ON1

GATE1

SENSE1

MON1

LED1

LED2

GND1 GND2

ID

SETTING

A0 A1

1

R

2

R

3

MAX5970

IRNG1

IRNG2

1µF

BIAS

REG

10I

DREG

1µF

DGND

AGND

HWEN

TEST

CONFIGURATION

MODE

POL

SETTINGS

RETRY

PROT

10 _____________________________________________________________________________________

0V to 16V, Dual Hot-Swap Controller with 10-Bit

Current and Voltage Monitor and 4 LED Drivers

Block Diagram

DREG

FAULT_

2

MAX5970

2

IRNG_

SENSE_

MON_

GATE_

GND_

FROM

CONFIGURATION

REGISTERS

DAC SELECT

REF

CHARGE

PUMP

5

µA

GATE

PULLDOWN

2MHz

ATTENUATOR

CS AMP

VOLTAGE SCALING

OSCILLATOR

2

MUX

SCOMP

FCOMP

1V

LOGIC

BLOCK

2

C

2

I

PG_

LED_

HWEN

RETRY

MODE

ON_

POL

PROT

BIAS

SDA

SCL

A0

A1

ALERT

2

REG

UVLO

IN

LDO IREF

IDEF

10-BIT ADC

(SAR)

CIRCULAR

BUFF

DGNDAGND

______________________________________________________________________________________ 11

0V to 16V, Dual Hot-Swap Controller with 10-Bit Current and Voltage Monitor and 4 LED Drivers

Detailed Description

The MAX5970 includes a set of registers that are accessed through the I2C interface. Some of the registers

Table 1a. Register Address Map (Channel Specific)

MAX5970

REGISTER DESCRIPTION CHANNEL 1 CHANNEL 2

adc_chx_cs_msb

adc_chx_cs_lsb

adc_chx_mon_msb

adc_chx_mon_ lsb

min_chx_cs_msb

min_chx_cs_ lsb

max_chx_cs_msb

max_chx_cs_ lsb

min_chx_mon_msb

min_chx_mon_ lsb

max_chx_mon_msb

max_chx_mon_ lsb

uv1thr _chx_msb

uv1thr_chx_ lsb

uv2thr_chx_msb

uv2thr_chx_ lsb

ov1thr_chx_msb

ov1thr_chx_ lsb

High 8 bits ([9:2]) of latest current-signal ADC result

Low 2 bits ([1:0]) of latest current-signal ADC result

High 8 bits ([9:2]) of latest voltage-signal ADC result

Low 2 bits ([1:0]) of latest voltage-signal ADC result

High 8 bits ([9:2]) of current-signal minimum value

Low 2 bits ([1:0]) of current-signal minimum value

High 8 bits ([9:2]) of current-signal maximum value

Low 2 bits ([1:0]) of current-signal maximum value

High 8 bits ([9:2]) of voltage-signal minimum value

Low 2 bits ([1:0]) of voltage-signal minimum value

High 8 bits ([9:2]) of voltage-signal maximum value

Low 2 bits ([1:0]) of voltage-signal maximum value

High 8 bits ([9:2]) of undervoltage warning (UV1) threshold

Low 2 bits ([1:0]) of undervoltage warning (UV1) threshold

High 8 bits ([9:2]) of undervoltage critical (UV2) threshold

Low 2 bits ([1:0]) of undervoltage critical (UV2) threshold

High 8 bits ([9:2]) of overvoltage warning (OV1) threshold

Low 2 bits ([1:0]) of overvoltage warning (OV1) threshold

are read only and some of the registers are read and write that are updated to configure the MAX5970 for a specific operation. See Tables 1a and 1b for the registers map.

RESET VALUE

0x00 0x04 — R

0x01 0x05 — R

0x02 0x06 — R

0x03 0x07 — R

0x08 0x10 0xFF R

0x09 0x11 0x03 R

0x0A 0x12 0x00 R

0x0B 0x13 0x00 R

0x0C 0x14 0xFF R

0x0D 0x15 0x03 R

0x0E 0x16 0x00 R

0x0F 0x17 0x00 R

0x1A 0x24 0x00 R/W

0x1B 0x25 0x00 R/W

0x1C 0x26 0x00 R/W

0x1D 0x27 0x00 R/W

0x1E 0x28 0xFF R/W

0x1F 0x29 0x03 R/W

READ/

WRITE

12 _____________________________________________________________________________________

0V to 16V, Dual Hot-Swap Controller with 10-Bit

Current and Voltage Monitor and 4 LED Drivers

Table 1a. Register Address Map (Channel Specific) (continued)

REGISTER DESCRIPTION CHANNEL 1 CHANNEL 2

ov2thr_chx_msb

ov2thr_chx_ lsb

oithr_chx_msb

oithr_chx_ lsb

dac_chx-fast Fast-comparator threshold DAC setting 0x2E 0x2F 0xBF R/W

cubf_ba_chx_v

cubf_ba_chx_i

High 8 bits ([9:2]) of overvoltage critical (OV2) threshold

Low 2 bits ([1:0]) of overvoltage critical (OV2) threshold

High 8 bits ([9:2]) of overcurrent warning threshold

Low 2 bits ([1:0]) of overcurrent warning threshold

Base address for block read of 50-sample voltage-signal data buffer

Base address for block read of 50-sample current-signal data buffer

0x20 0x2A 0xFF R/W

0x21 0x2B 0x03 R/W

0x22 0x2C 0xFF R/W

0x23 0x2D 0x03 R/W

0x46 0x48 — R

0x47 0x49 — R

RESET VALUE

Table 1b. Register Address Map (General)

REGISTER DESCRIPTION

mon_range MON input range setting 0x18 0x00 R/W cbuf_chx_store Selective enabling of circular buffer 0x19 0x0F R/W ifast2slow Current threshold fast-to-slow ratio setting 0x30 0x0F R/W status0 Slow-trip and fast-trip comparators status register 0x31 0x00 R status1 PROT, MODE, and ON_ inputs status register 0x32 — R

status2

status3 fault0 Status register for undervoltage detection (warning or critical) 0x35 0x00 R/C fault1 Status register for overvoltage detection (warning or critical) 0x36 0x00 R/C fault2 Status register for overcurrent detection (warning) 0x37 0x00 R/C pgdly Delay setting between MON measurement and PG_ assertion 0x38 0x00 R/W fokey Load register with 0xA5 to enable force-on function 0x39 0x00 R/W foset Register that enables force-on function for a channel 0x3A 0x00 R/W chxen Channel enable bits 0x3B — R/W dgl_i OC deglitch enable bits 0x3C 0x00 R/W dgl_uv UV deglitch enable bits 0x3D 0x00 R/W dgl_ov OV deglitch enable bits 0x3E 0x00 R/W cbufrd_hibyonly Circular buffers readout mode: 8 bit or 10 bit 0x3F 0x0F R/W

cbuf_dly_stop

peak_log_rst Reset control bits for peak-detection registers 0x41 0x00 R/W peak_log_hold Hold control bits for peak-detection registers 0x42 0x00 R/W

Fast-trip threshold maximum range setting bits, from IRNG_ three-state inputs

LATCH, POL, ALERT, and PG_ status register

Circular buffer stop-delay. Number of samples recorded to the circular buffer after channel shutdown.

ADDRESS

(HEX CODE)

0x33 — R/W

0x34 — R

0x40 0x19 R/W

RESET VALUE

READ/

WRITE

READ/ WRITE

MAX5970

______________________________________________________________________________________ 13