MAXIM MAX5932

19-3264; Rev 0; 4/04
KIT
ATION
EVALU
LE
B
A
IL
A
AV
Positive High-Voltage, Hot-Swap Controller
The MAX5932 is a fully integrated hot-swap controller for
+9V to +80V positive supply rails. The MAX5932 allows
for the safe insertion and removal of circuit cards into a
live backplane without causing glitches on the backplane power-supply rail. This device is pin and function
compatible to LT1641-1. The MAX5932 features a programmable foldback-current limit. If the device remains
in current limit for more than a programmable time, the
external n-channel MOSFET latches off. Other features
include a programmable undervoltage lockout and a
programmable output-voltage slew rate through an
external n-channel MOSFET.
The MAX5932 provides a power-good output (PWRGD)
to indicate the status of the output voltage. For a variety
of PWRGD/PWRGD, latch/autoretry-fault management,
autoretry duty-cycle options, refer to the MAX5933 and
MAX5934 data sheets.
The MAX5932 operates in the -40°C to +85°C extended
temperature range. This device is available in an
8-pin SO package.
Features
♦ Pin and Function Compatible with LT1641-1
♦ Provides Safe Hot Swap for +9V to +80V Power
Supplies
♦ Safe Board Insertion and Removal from Live
Backplanes
♦ Active-High Power-Good Output (PWRGD)
♦ Programmable Foldback-Current Limiting
♦ High-Side Drive for an External N-Channel MOSFET
♦ Undervoltage Lockout (UVLO)
♦ Overvoltage Protection
♦ Latched Fault Management
♦ User-Programmable Supply Voltage
Power-Up Rate
Ordering Information
Applications
Hot Board Insertion
Electronic Circuit Breaker
PART
MAX5932ESA
TEMP RANGE
PIN-PACKAGE
-40°C to +85°C
8 SO
Industrial High-Side Switch/Circuit Breaker
Network Routers and Switches
24V/48V Industrial/Alarm Systems
Pin Configuration
TOP VIEW
Typical Application Circuit appears at end of data sheet.
ON 1
8
VCC
7
SENSE
3
6
GATE
GND 4
5
TIMER
FB 2
MAX5932
PWRGD
SO
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX5932
General Description
MAX5932
Positive High-Voltage, Hot-Swap Controller
ABSOLUTE MAXIMUM RATINGS
(Voltages referenced to GND)
VCC .........................................................................-0.3V to +85V
SENSE, FB, ON ..........................................-0.3V to (VCC + 0.3V)
TIMER, PWRGD......................................................-0.3V to +85V
GATE ......................................................................-0.3V to +95V
Maximum GATE Current ....................................-50mA, +150mA
Maximum Current into Any Other Pin................................±50mA
Continuous Power Dissipation (TA = +70°C)
8-Pin SO (derate 5.9mW/°C above +70°C)..................470mW
Operating Temperature Range ...........................-40°C to +85°C
Maximum Junction Temperature .....................................+150°C
Storage Temperature Range .............................-60°C to +150°C
ESD Rating (Human Body Model)......................................2000V
Lead Temperature (soldering, 10s) .................................+300°C
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.
ELECTRICAL CHARACTERISTICS
(VCC = +24V, GND = 0V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
Supply Voltage Range
VCC
Supply Current
ICC
CONDITIONS
MIN
TYP
MAX
80
V
1.4
3.5
mA
8.3
8.8
V
9
VON = 3V, VCC = 80V
VCC Undervoltage Lockout
VLKO
VCC Undervoltage Lockout
Hysteresis
VLKOHYST
FB High-Voltage Threshold
VFBH
FB low-to-high transition
1.280
1.313
1.345
VFBL
FB high-to-low transition
1.221
1.233
1.245
FB Low-Voltage Threshold
FB Hysteresis
FB Input Bias Current
FB Threshold Line Regulation
VCC low-to-high transition
7.5
0.4
VFBHYST
V
80
IINFB
VFB = 0V
∆VFB
9V ≤ VCC ≤ 80V, ON = 0V,
TA = 0°C to +70°C
-1
UNITS
V
V
mV
+1
µA
0.05
mV/V
VFB = 0V, TA = 0°C to +70°C
8
12
17
VFB = 1V, TA = 0°C to +70°C
39
47
55
IGATEUP
Charge pump on, VGATE = 7V
-5
-10
-20
µA
IGATEDN
Any fault condition, VGATE = 2V
mA
SENSE Trip Voltage
(VCC - VSENSE)
VSENSETRIP
GATE Pullup Current
GATE Pulldown Current
35
70
100
VCC = 10.8V to 20V
4.5
6.2
18
VCC = 20V to 80V
10
13.6
18
mV
∆VGATE
VGATE - VCC
TIMER Pullup Current
ITIMERUP
VTIMER = 0V
-24
-80
-120
µA
TIMER Pulldown Current
ITIMERON
VTIMER = 1V
1.5
3
4.5
µA
ON Logic-High Threshold
VONH
ON low-to-high transition
1.280
1.313
1.355
V
ON Logic-Low Threshold
VONL
ON high-to-low transition
1.221
1.233
1.245
External N-Channel Gate Drive
ON Hysteresis
ON Input Bias Current
PWRGD Leakage Current
PWRGD Output Low Voltage
SENSE Input Bias Current
Thermal Shutdown
Thermal Shutdown Hysteresis
2
VONHYST
IINON
IOH
VOL
ISENSE
80
VON = 0V
V
mV
+1
µA
VPWRGD = 80V
10
µA
IO = 2mA
0.4
IO = 4mA
2.5
VSENSE = 0V to VCC
Temperature rising
-1
V
-1
+3
V
µA
150
°C
20
°C
_______________________________________________________________________________________
Positive High-Voltage, Hot-Swap Controller
(VCC = +24V, GND = 0V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
ON Low-to-GATE Low
Propagation Delay
tPHLON
CGATE = 0, Figures 1, 2
6
µs
ON High-to-GATE High
Propagation Delay
tPLHON
CGATE = 0, Figures 1, 2
1.7
µs
FB Low-to-PWRGD Low
Propagation Delay
tPHLFB
Figures 1, 3
3.2
µs
FB High-to-PWRGD High
Propagation Delay
tPLHFB
Figures 1, 3
1.5
µs
(VCC - VSENSE) High-to-GATE
Low Propagation Delay
tPHLSENSE
TA = +25°C, CGATE = 0, Figures 1, 4
0.5
2
µs
Note 1: All currents into the device are positive and all currents out of the device are negative. All voltages are referenced to
ground, unless noted otherwise.
_______________________________________________________________________________________
3
MAX5932
ELECTRICAL CHARACTERISTICS (continued)
Positive High-Voltage, Hot-Swap Controller
MAX5932
Test Circuit and Timing Diagrams
ON
VCC
24V
MAX5932
FB
SENSE
1.313V
1.233V
ON
tPLHON
5V
PWRGD
GATE
5kΩ
GND
Figure 2. ON to GATE Timing
1.313V
1.233V
VCC - SENSE
tPHLFB
GATE
FB
tPLHFB
1V
Figure 3. FB to PWRGD Timing
4
1V
TIMER
Figure 1. Test Circuit
PWRGD
5V
GATE
10nF
tPHLON
1V
47mV
tPHLSENSE
VCC
Figure 4. SENSE to GATE Timing
_______________________________________________________________________________________
Positive High-Voltage, Hot-Swap Controller
ICC (mA)
1.5
1.245
2.0
TA = +85°C
TA = +25°C
2.5
FB LOW-VOLTAGE THRESHOLD (V)
2.1
1.250
MAX5932 toc02
2.4
1.2
VCC = 48V
1.5
0.9
1.0
TA = -40°C
0.6
VCC = 24V
0.5
0.3
1.235
1.230
1.225
1.220
1.215
1.210
1.205
0
0
8
16 24 32 40 48 56 64 72 80
1.200
-40
-15
10
35
85
60
-40
10
35
60
TEMPERATURE (°C)
TEMPERATURE (°C)
FB HIGH-VOLTAGE THRESHOLD
vs. TEMPERATURE
FB HYSTERESIS vs. TEMPERATURE
IGATE PULLUP CURRENT
vs. TEMPERATURE
0.11
1.330
1.325
0.10
FB HYSTERESIS (V)
1.320
1.315
1.310
1.305
1.300
-5
-6
IGATE PULLUP CURRENT (µA)
MAX5932 toc04
1.335
0.09
0.08
0.07
0.06
1.295
1.290
0.05
0.04
1.280
-15
10
35
60
-15
10
35
85
60
-10
-11
-15
35
12
11
10
9
8
VCC = 10.8V
60
85
MAX5932 toc08
16
14
GATE DRIVE (VGATE - VCC) (V)
VCC = 48V
13
10
TEMPERATURE (°C)
GATE DRIVE vs. VCC
MAX5932 toc07
GATE DRIVE (VGATE - VCC) (V)
-9
-40
GATE DRIVE vs. TEMPERATURE
15
7
-8
TEMPERATURE (°C)
TEMPERATURE (°C)
14
-7
-13
-40
85
85
-12
1.285
-40
-15
VCC (V)
MAX5932 toc05
0
FB HIGH-VOLTAGE THRESHOLD (V)
1.240
MAX5932 toc06
ICC (mA)
3.0
MAX5932 toc01
2.7
1.8
FB LOW-VOLTAGE THRESHOLD
vs. TEMPERATURE
ICC vs. TEMPERATURE
MAX5932 toc03
ICC vs. VCC
12
10
8
6
4
2
6
5
0
-40
-15
10
35
TEMPERATURE (°C)
60
85
0
20
40
60
80
VCC (V)
_______________________________________________________________________________________
5
MAX5932
Typical Operating Characteristics
(VCC = +48V, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VCC = +48V, TA = +25°C, unless otherwise noted.)
TIMER PULLUP CURRENT
vs. TEMPERATURE
ON HIGH-VOLTAGE THRESHOLD
vs. TEMPERATURE
TIMER PULLUP CURRENT vs. VCC
-70
-75
-80
TA = +85°C
TA = +25°C
-75
-76
TA = 0°C
-77
TA = -40°C
-78
-85
-79
-90
-40
-15
10
35
1.323
1.313
1.303
1.293
10
20
30
40
50
60
80
70
-40
1.245
1.235
1.225
MAX5932 toc13
0.081
0.079
0.077
0.075
1.215
1.205
0.073
-40
-15
10
35
60
85
-40
-15
TEMPERATURE (°C)
85
14
12
10
8
6
TA = -40°C
MAX5932 toc15
16
TA = +85°C
60
50
SENSE REGULATION VOLTAGE (mV)
MAX5932 toc14
18
TA = +25°C
35
SENSE REGULATION VOLTAGE vs. VFB
PWRGD VOUT LOW vs. ILOAD
4
10
TEMPERATURE (°C)
20
PWRGD VOUT LOW (V)
60
ON HYSTERESIS vs. TEMPERATURE
ON HYSTERESIS (V)
1.255
35
0.083
MAX5932 toc12
1.265
10
TEMPERATURE (°C)
ON LOW-VOLTAGE THRESHOLD
vs. TEMPERATURE
45
40
35
30
25
20
15
10
5
2
0
0
10
30
50
ILOAD (mA)
6
-15
VCC (V)
TEMPERATURE (°C)
ON LOW-VOLTAGE THRESHOLD (V)
1.333
1.283
0
85
60
MAX5932 toc11
-74
1.343
ON HIGH-VOLTAGE THRESHOLD (V)
TIMER PULLUP CURRENT (µA)
-65
MAX5932 toc10
-73
MAX5932 toc09
-60
TIMER PULLUP CURRENT (µA)
MAX5932
Positive High-Voltage, Hot-Swap Controller
70
90
0
0.2
0.4
0.6
0.8
VFB (V)
_______________________________________________________________________________________
1.0
85
Positive High-Voltage, Hot-Swap Controller
PIN
NAME
FUNCTION
1
ON
On/Off Control Input. ON is used to implement the undervoltage lockout threshold and resets the part after
a fault condition (see the Detailed Description section).
2
FB
Power-Good Comparator Input. Connect a resistive divider from output to FB to GND to monitor the output
voltage (see the Power-Good Detection section). FB is also used as a feedback for the current-limit
foldback function.
3
PWRGD
Open-Drain Power-Good Output. PWRGD is high when VFB is higher than VFBH. PWRGD is low when VFB
is lower than VFBL.
4
GND
Ground
Timing Input. Connect a capacitor from TIMER to GND to program the maximum time the part is allowed to
remain in current limit (see the TIMER section).
5
TIMER
6
GATE
Gate-Drive Output. The high-side gate drive for the external n-channel MOSFET (see the GATE section).
7
SENSE
Current-Sense Input. Connect a sense resistor from VCC to SENSE and the drain of the external n-channel
MOSFET.
8
VCC
Power-Supply Input. Bypass VCC to GND with a 0.1µF capacitor. Input voltage range is from +9V to +80V.
_______________________________________________________________________________________
7
MAX5932
Pin Description
Positive High-Voltage, Hot-Swap Controller
MAX5932
Functional Diagram
FB
VCC SENSE
MAX5932
VP GEN
CHARGE
PUMP
AND
GATE
DRIVER
REF
GEN
0.5V
PWRGD
GATE
OPEN
DRAIN
1.233V
ON
VCC
UNDERVOLTAGE
LOCKOUT
8.3V
LOGIC
VP
0.5V
80µA
1.233V
TIMER
3µA
GND
8
_______________________________________________________________________________________
Positive High-Voltage, Hot-Swap Controller
The MAX5932 monitors the input voltage, the output voltage, the output current, and the die temperature. This
device features a power-good output (PWRGD) to indicate the status of the output voltage by monitoring the
voltage at FB (see the Power-Good Detection section).
As shown in Figure 5, a sense resistor is connected
between VCC and SENSE to sense the load current.
The device regulates the voltage across the sense
resistor (VIN - VSENSE) to 47mV when the voltage at FB
≥ 0.5V. The current-limit threshold (V SENSETRIP )
decreases linearly from 47mV to 12mV as FB decreases
from 0.5V to 0V.
An undervoltage fault is detected when ON goes below
the threshold, VONL = 1.233V, which causes the voltage
at GATE to go low, and results in turning off the MOSFET.
To turn the MOSFET on again, ON must pass the VONH =
1.313V threshold.
The MAX5932 is a fully integrated hot-swap controller
for positive supply rails. The device allows for the safe
insertion and removal of circuit cards into live backplanes
without causing glitches on the backplane power-supply
rail. During startup the MAX5932 acts as a current regulator using an external sense resistor and MOSFET to limit
the amount of current drawn by the load.
The MAX5932 features latched-off fault management.
When an overcurrent or an overtemperature fault
occurs, the MAX5932 turns the external MOSFET off
and keeps it off. After the fault condition goes away,
cycle the power supply or toggle ON low and high
again to unlatch the device.
The MAX5932 operates from +9V to +80V supply voltage range and has a default undervoltage lockout
(UVLO) set to +8.3V. The UVLO threshold is adjustable
using a resistive divider connected from VCC to ON to
GND (see R1 and R2 in Figure 5).
RSENSE
0.025Ω
VIN
24V
Q1
IRF530
CL
R1
49.9kΩ
1%
R5
10Ω
5%
R6
1kΩ
5%
0.1µF
8
VCC
1
7
SENSE
TIMER
R7
24kΩ
5%
C1
10nF
GATE
2
R4
3.57kΩ
1%
MAX5932
5
R3
59kΩ
1%
6
FB
ON
R2
3.4kΩ
1%
C2
0.68µF
D1
CMPZ5248B
PWRGD
3
PWRGD
GND
4
GND
Figure 5. Application Circuit
_______________________________________________________________________________________
9
MAX5932
Detailed Description
MAX5932
Positive High-Voltage, Hot-Swap Controller
Applications Information
Hot-Circuit Insertion
When circuit boards are inserted into a live backplane,
the supply bypass capacitors on the boards draw high
peak currents from the backplane power bus as they
charge up. The transient currents can permanently
damage the connector pins and glitch the system supply, causing other boards in the system to reset.
Power-Up Sequence
The power supply on a board is controlled by placing
an external n-channel MOSFET (Q1) in the power path
(Figure 5). Resistor RSENSE provides current detection
and capacitor C1 provides control of the GATE slew
rate. Resistor R6 provides current control-loop compensation while R5 prevents high-frequency oscillations in
Q1. Resistors R1 and R2 provide undervoltage sensing.
After the power pins first make contact, transistor Q1 is
turned off. When the voltage at ON exceeds the turn-on
threshold voltage, the voltage on VCC exceeds the undervoltage lockout threshold, and the voltage on TIMER is
less than 1.233V, transistor Q1 turns on (Figure 6).
The voltage at GATE rises with a slope equal to
10µA/C1 and the supply inrush current is set at:
IINRUSH = CL x 10µA/C1
When the voltage across the current-sense resistor
RSENSE reaches VSENSETRIP, then the inrush current is
limited by the internal current-limit circuitry that adjusts
the voltage on GATE to maintain a constant voltage
across the sense resistor.
Once the voltage at the output has reached its final value,
as sensed by resistors R3 and R4, PWRGD goes high.
POWER-UP WAVEFORMS
Short-Circuit Protection
The MAX5932 features a programmable foldback current
limit with an electronic circuit breaker that protects
against short circuits or excessive supply currents. The
current limit is set by placing a sense resistor between
VCC (pin 8) and SENSE (pin 7).
To prevent excessive power dissipation in the pass
transistor and to prevent voltage spikes on the input
supply during short-circuit conditions at the output, the
current folds back as a function of the output voltage
that is sensed at FB (Figure 7).
When the voltage at FB is 0V, the current-limit circuit
drives GATE to force a constant 12mV drop across the
sense resistor. As the output voltage at FB increases,
the voltage across the sense resistor increases until FB
reaches 0.5V, at the point that the voltage across the
sense resistor is held constant at 47mV.
The maximum current limit is calculated as:
ILIMIT = 47mV/RSENSE
For a 0.025Ω sense resistor, the current limit is set at
1.88A and folds back to 480mA when the output is
shorted to ground.
The MAX5932 also features a variable overcurrent
response time. The time required to regulate Q1’s drain
current depends on:
• Q1’s input capacitance.
• GATE capacitor C1 and compensation resistor R6.
• The internal delay from SENSE to GATE.
Figure 8 shows the delay from a voltage step at SENSE
until GATE voltage starts falling, as a function of
overdrive.
VCC - VSENSE
GATE
50V/div
47mV
ISENSE
2A/div
OUTPUT
50V/div
12mV
PWRGD
50V/div
0V
0.5V
VFB
20ms/div
Figure 6. Power-Up Waveforms
10
Figure 7. Current-Limit Sense Voltage vs. Feedback Voltage
______________________________________________________________________________________
Positive High-Voltage, Hot-Swap Controller
SHORT-CIRCUIT WAVEFORMS
OUTPUT
50V/div
12
PROPAGATION DELAY (µs)
MAX5932
RESPONSE TIME TO OVERCURRENT
14
10
ISENSE
1A/div
8
GATE
50V/div
6
4
TIMER
1V/div
2
0
0
100
200
300
10ms/div
VCC - VSENSE (mV)
Figure 8. Response Time to Overcurrent
Figure 9. Short-Circuit Waveforms
TIMER
TIMER provides a method for programming the maximum time the device is allowed to operate in current
limit. When the current-limit circuitry is not active,
TIMER is pulled to GND by a 3µA current source. After
the current-limit circuit becomes active, an 80µA pullup
current source is connected to TIMER and the voltage
rises with a slope equal to 77µA/CTIMER as long as the
current-limit circuit remains active. Once the desired
maximum current-limit time is chosen, the capacitor
value is calculated using the following equations:
C(nF) = 65 x t(ms)
or
TLIMIT = (CTIMER/80µA) x 1.233V
When the current-limit circuit turns off, TIMER is discharged to GND by the 3µA current source.
Whenever TIMER reaches 1.233V, the internal fault
latch is set. GATE is immediately pulled to GND and
TIMER is pulled back to GND by the 3µA current
source. When TIMER falls below 0.5V, ON is pulsed low
to reset the internal fault latch.
The waveform in Figure 9 shows how the output latches
off following a short circuit. The drop across the sense
resistor is held at 12mV as the timer ramps up. Since
the output did not rise, FB remains below 0.5V and the
circuit latches off. For Figure 9, CT = 100nF.
Undervoltage and Overvoltage Detection
ON can be used to detect an undervoltage condition at
the power-supply input. ON is internally connected to
an analog comparator with 80mV of hysteresis. If ON
falls below its threshold voltage (1.233V), GATE is
pulled low and is held low until ON is high again.
Figure 10 shows an overvoltage detection circuit. When
the input voltage exceeds the Zener diode’s breakdown
voltage, D1 turns on and starts to pull TIMER high. After
TIMER is pulled higher than 1.233V, the fault latch is set
and GATE is pulled to GND immediately, turning off
transistor Q1 (see Figure 11). Operation is restored
either by interrupting power or by pulsing ON low.
Power-Good Detection
The MAX5932 includes a comparator for monitoring the
output voltage. The noninverting input (FB) is compared against an internal 1.233V precision reference
and exhibits 80mV hysteresis. The comparator’s output
(PWRGD) is an open drain one capable of operating
from a pullup as high as 80V.
The PWRGD can be used to directly enable/disable a
power module with an active-high enable input. Figure
12 shows how to use PWRGD to control an active-low
enable-input power module. Signal inversion is accomplished by transistor Q2 and R7 or use MAX5933.
Supply Transient Protection
The MAX5932 is 100% tested and guaranteed to be
safe from damage with supply voltages up to 80V.
However, spikes above 85V may damage the device.
During a short-circuit condition, the large change in
currents flowing through the power-supply traces can
cause inductive voltage spikes that could exceed 85V.
To minimize the spikes, the power-trace parasitic
inductance should be minimized by using wider traces
or heavier trace plating and a 0.1µF bypass capacitor
placed between V CC and GND. A transient voltage
suppressor (TVS) at the input can also prevent damage
from voltage surges.
______________________________________________________________________________________
11
MAX5932
Positive High-Voltage, Hot-Swap Controller
RSENSE
0.025Ω
Q1
IRF530
VIN
CL
SHORT
PIN
R1
49.9kΩ
1%
D1
30V
1N5256B
R5
10Ω
5%
0.1µF
8
VCC
1
D2
CMPZ5248B
7
SENSE
R6
1kΩ
5%
C1
10nF
GATE
2
R4
3.57kΩ
1%
MAX5932
R2
3.4kΩ
1%
5
TIMER
C2
0.68µF
R7
24kΩ
5%
6
FB
ON
R3
59kΩ
1%
PWRGD
3
PWRGD
GND
4
GND
Figure 10. Overvoltage Detection
GATE Voltage
OVERVOLTAGE WAVEFORMS
IN
50V/div
ISENSE
5A/div
GATE
50V/div
A curve of Gate Drive vs. VCC is shown in Figure 13.
GATE is clamped to a maximum voltage of 18V above the
input voltage. At a minimum input-supply voltage of 9V,
the minimum gate-drive voltage is 4.5V. When the inputsupply voltage is higher than 20V, the gate-drive voltage
is at least 10V and a standard n-channel MOSFET can be
used. In applications over a 9V to 20V range, a logic-level
n-FET must be used with a proper protection Zener diode
between its gate and source (as D1 shown in Figure 5).
Thermal Shutdown
TIMER
10V/div
OUTPUT
50V/div
10µs/div
If the MAX5932 die temperature reaches +150°C, an
overtemperature fault is generated. As a result, GATE
goes low and turns the external MOSFET off. The
MAX5932 die temperature must cool down below +130°C
before the overtemperature fault condition is removed.
Figure 11. Overvoltage Waveforms
12
______________________________________________________________________________________
Positive High-Voltage, Hot-Swap Controller
Q1
IRF530
VIN
SHORT
PIN
R1
294kΩ
1%
0.1µF
8
1
D1
CMPZ5248B
R5
10Ω
5%
7
SENSE
VCC
R6
1kΩ
5%
5
TIMER
CL
220µF
VIN+
VOUT+
VOUT
ON/OFF
VIN-
VOUT-
2
R4
4.22kΩ
1%
PWRGD
C2
0.68µF
R7
47kΩ
5%
C1
10nF
GATE
FB
ON
R3
143kΩ
1%
6
MAX5932
R2
10.2kΩ
1%
MAX5932
RSENSE
0.01Ω
3
GND
4
GND
Figure 12. Active-Low Enable Module
Layout Considerations
GATE DRIVE vs. VCC
16
GATE DRIVE (VGATE - VCC) (V)
14
12
10
8
6
4
2
0
0
20
40
VCC (V)
60
80
To achieve accurate current sensing, a Kelvin connection
is recommended. The minimum trace width for 1oz copper foil is 0.02in per amplifier to make sure the trace stays
at a reasonable temperature. Using 0.03in per amplifier
or wider is recommended. Note that 1oz copper exhibits
a sheet resistance of about 530µΩ/square. Small resistances add up quickly in high-current applications. To
improve noise immunity, connect the resistor-divider to
ON close to the device and keep traces to VCC and GND
short. A 0.1µF capacitor from ON to GND also helps
reject induced noise. Figure 14 shows a layout that
addresses these issues.
External MOSFET must be thermally coupled to the
MAX5932 to ensure proper thermal shutdown operation
(see Figure 14).
Figure 13. Gate Drive vs. Supply Voltage
______________________________________________________________________________________
13
Positive High-Voltage, Hot-Swap Controller
MAX5932
Chip Information
TRANSISTOR COUNT: 1573
PROCESS: BiCMOS
IRF530
Figure 14. Recommended Layout for R1, R2, and RSENSE
Typical Application Circuit
RSENSE
0.01Ω
Q1
IRF530
VIN
CL
*SMBJ51A
R1
49.9kΩ
1%
R5
10Ω
5%
0.1µF
8
VCC
1
7
SENSE
R6
1kΩ
5%
TIMER
R7
24kΩ
5%
C1
10nF
GATE
2
R4
3.57kΩ
1%
MAX5932
5
R3
59kΩ
1%
6
FB
ON
R2
3.4kΩ
1%
C2
0.68µF
D1
CMPZ5248B
PWRGD
3
GND
4
GND
*DIODES, INC.
14
______________________________________________________________________________________
PWRGD
Positive High-Voltage, Hot-Swap Controller
N
E
H
INCHES
MILLIMETERS
MAX
MIN
0.069
0.053
0.010
0.004
0.014
0.019
0.007
0.010
0.050 BSC
0.150
0.157
0.228
0.244
0.016
0.050
MAX
MIN
1.35
1.75
0.10
0.25
0.35
0.49
0.19
0.25
1.27 BSC
3.80
4.00
5.80
6.20
0.40
SOICN .EPS
DIM
A
A1
B
C
e
E
H
L
1.27
VARIATIONS:
1
INCHES
TOP VIEW
DIM
D
D
D
MIN
0.189
0.337
0.386
MAX
0.197
0.344
0.394
MILLIMETERS
MIN
4.80
8.55
9.80
MAX
5.00
8.75
10.00
N MS012
8
AA
14
AB
16
AC
D
A
B
e
C
0∞-8∞
A1
L
FRONT VIEW
SIDE VIEW
PROPRIETARY INFORMATION
TITLE:
PACKAGE OUTLINE, .150" SOIC
APPROVAL
DOCUMENT CONTROL NO.
21-0041
REV.
B
1
1
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15
© 2004 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
MAX5932
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)