MAX181AEQH+D [MAXIM]
ADC, Successive Approximation, 12-Bit, 1 Func, 8 Channel, Parallel, Word Access, PQCC44, PLASTIC, LCC-44;
| 型号： | MAX181AEQH+D |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | ADC, Successive Approximation, 12-Bit, 1 Func, 8 Channel, Parallel, Word Access, PQCC44, PLASTIC, LCC-44 稳压器 网络接口 |
| 文件： | 总8页 (文件大小：265K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-1678; Rev 0; 4/00
Network Interface Card Smart Regulator
General Description
Features
The MAX1810 powers peripheral component intercon-
nect (PCI) Ethernet network interface cards (NICs),
modem cards, and other devices that utilize both the
main and auxiliary (standby) voltages supplied by PCI-
compliant systems. The device generates an uninter-
rupted +3.3V at up to 500mA from either a +5V main or
a +5V standby supply. When both +5V inputs fall below
+4.1V, an internal switch connects the +3.3V auxiliary
input to the output.
ꢀ Uninterrupted +3.3V Output
ꢀ Up to 500mA Output Current
ꢀ High-Power 0.9W SO-8 Package
ꢀ Thermal and Overcurrent Protection
ꢀ Only 1µF Output Capacitor
ꢀ Internal 0.18Ω +3.3V Auxiliary Switch
An auxiliary switch resistance of only 0.18Ω minimizes
output droop from the +3.3V auxiliary supply. In addi-
tion, the MAX1810 guarantees that no reverse current
flows from the output to any unbiased or inactive input,
and remains stable with as little as 1µF of output
bypass capacitance at its output.
ꢀ No Reverse Current to Inactive Inputs
The MAX1810 is available in a compact 8-pin high-
power (0.9W) SO package.
Ordering Information
________________________Applications
PCI Adapter Cards
Network Interface Cards
Modem Cards
PART
TEMP. RANGE
-40oC to +85oC
PIN-PACKAGE
MAX1810ESA
8 SO
Typical Operating Circuit
Pin Configuration
TOP VIEW
OUT
+5V MAIN
INPUT
MAIN
STBY
AUX
OUT
+3.3V, 500mA
STBY
1
2
3
4
8
7
6
5
GND
GND
GND
GND
C
OUT
1.0µF
MAIN
OUT
AUX
+5V STBY
INPUT
MAX1810
MAX1810
+3.3V AUX
INPUT
GND
SO
________________________________________________________________ Maxim Integrated Products
1
For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
Network Interface Card Smart Regulator
ABSOLUTE MAXIMUM RATINGS
MAIN, STBY, AUX, OUT to GND ...........................-0.3V to +6.0V
OUT to AUX...........................................................-0.3V to +6.0V
OUT Maximum Output Current .......................................1750mA
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Continuous Power Dissipation (T = +70°C)
A
8-Pin SO (derate 11.75mW/°C above +70°C)..............900mW
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
(V
= V
= +5.0V, V
= +3.3V, T = 0°C to +85°C, unless otherwise noted. Typical values are at T = +25°C.)
MAIN
STBY
AUX
A
A
PARAMETER
CONDITIONS
MIN
4.5
TYP
MAX
5.5
UNITS
V
MAIN or STBY Input Range
AUX Input Range
3.0
3.6
V
Maximum Load Current
MAIN or STBY Quiescent Current
AUX Quiescent Current
500
mA
mA
mA
I
= 10mA
0.75
0.2
3
OUT
V
= V
= 0, V
= +3.6V
0.5
MAIN
STBY
AUX
Reverse Leakage from AUX to
MAIN or STBY
V
= +3.6V, V
or V
= 0
1
1
20
µA
µA
AUX
AUX
MAIN
STBY
Reverse Leakage from MAIN or
STBY to AUX
V
= 0, V
or V
= +5.5V
100
MAIN
STBY
OUT Load Capacitance
MAIN or STBY Detect Threshold
MAIN or STBY High Threshold
MAIN or STBY Hysteresis
OUT Voltage
C
ESR < 50mΩ
1
µF
V
OUT
MAIN or STBY falling
MAIN or STBY rising
3.925
3.234
4.100
4.275
4.475
V
150
3.3
mV
V
3.366
+4.5V < (V
or V
) < +5.5V, 0 < I
< 400mA
MAIN
STBY
OUT
OUT Line Regulation
+4.5V< (V
or V
) < +5.5V
0.01
0.22
72
%
MAIN
STBY
OUT Load Regulation
I
I
= 30mA to 400mA, V
= 400mA
or V = +5V
STBY
%
OUT
OUT
MAIN
AUX to OUT Voltage Drop
AUX Switch Resistance
AUX Disable Threshold
Thermal Shutdown
118
0.295
2.8
mV
Ω
MAIN = STBY = GND
0.180
2.5
V
170
20
°C
°C
mA
Thermal Shutdown Hysteresis
Current-Limit Threshold
V
= V
= 0
520
900
1750
AUX
OUT
2
_______________________________________________________________________________________
Network Interface Card Smart Regulator
ELECTRICAL CHARACTERISTICS
(V
= V
= +5.0V, V
= +3.3V, T = -40°C to +85°C, unless otherwise noted.) (Note 1)
MAIN
STBY
AUX
A
PARAMETER
CONDITIONS
MIN
4.5
MAX
5.5
UNITS
MAIN or STBY Input Range
AUX Input Range
V
V
3.0
3.6
Maximum Load Current
500
mA
MAIN or STBY Quiescent Current
I
= 10mA
3
mA
mA
µA
OUT
AUX Quiescent Current
V
V
= V
= 0, V
= +3.6V
0.5
20
MAIN
STBY
AUX
Reverse Leakage from AUX to
MAIN or STBY
= +3.6V, V
or V
= 0
AUX
AUX
MAIN
STBY
Reverse Leakage from MAIN or
STBY to AUX
V
= 0, V
or V
= +5.5V
100
µA
MAIN
STBY
MAIN or STBY Detect
Threshold
MAIN or STBY falling
MAIN or STBY rising
3.925
3.234
4.275
V
MAIN or STBY High Threshold
OUT Voltage
4.475
3.366
V
V
+4.5V < (V
or V
) < +5.5V, 0 < I
< 400mA
MAIN
STBY
OUT
AUX to OUT Voltage Drop
AUX Switch Resistance
AUX Disable Threshold
Current-Limit Threshold
I
= 400mA
118
0.295
2.8
mV
Ω
OUT
MAIN = STBY = GND
2.5
V
V
= V = 0
520
1750
mA
AUX
OUT
Note 1: Specifications to -40°C are guaranteed by design, not production tested.
Typical Operating Characteristics
(V
, V
= +5V, V
= +3.3V, C
= 1µF, T = +25°C unless otherwise noted.)
MAIN STBY
AUX
OUT
A
OUTPUT VOLTAGE
vs. AUX INPUT VOLTAGE
OUTPUT VOLTAGE vs.
OUTPUT CURRENT (MAIN OR STANDBY)
MAIN OR STANDBY
UNDERVOLTAGE LOCKOUT
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
3.35
3.30
3.25
3.20
3.15
3.10
3.05
3.00
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
I
= 250mA
OUT
AUX SWITCH ON
AUX SWITCH OFF
AUX BODY DIODE ACTIVE
V
OUT
AND V
= 0
STBY
MAIN
= 100mA
I
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5
AUX INPUT VOLTAGE (V)
0
100
200
300
400
500
600
0
1
2
3
4
5
OUTPUT CURRENT (mA)
INPUT VOLTAGE (V)
_______________________________________________________________________________________
3
Network Interface Card Smart Regulator
Typical Operating Characteristics (continued)
(V
, V
= +5V, V
= +3.3V, C
= 1µF, T = +25°C unless otherwise noted.)
MAIN STBY
AUX
OUT
A
GROUND CURRENT vs.
INPUT VOLTAGE (MAIN OR STANDBY)
GROUND CURRENT
vs. INPUT VOLTAGE (AUX)
OUTPUT VOLTAGE
vs. OUTPUT CURRENT (AUX)
1000
250
200
150
100
50
900
800
3.9
3.7
3.5
3.3
3.1
2.9
2.7
2.5
I
= 250mA
OUT
700
600
500
400
300
200
100
0
AUX SWITCH ON
I
= 0
OUT
V
OUT
AND V
= 0
STBY
MAIN
= 0
I
0
0
1
2
3
4
5
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5
AUX INPUT VOLTAGE (V)
0
100
200
300
400
500
600
INPUT VOLTAGE (V)
OUTPUT CURRENT (mA)
GROUND CURRENT vs.
OUTPUT CURRENT (MAIN OR STANDBY)
GROUND CURRENT
vs. OUTPUT CURRENT (AUX)
AUX ON-RESISTANCE
vs. INPUT VOLTAGE
1400
1200
1000
800
600
400
200
0
240
220
200
180
160
140
120
100
250
230
210
190
170
150
V
AND V
= 0
STBY
I
= 400 mA
MAIN
OUT
V
= 5V
IN
V
= 4.2V
IN
0
100
200
300
400
500
600
0
100
200
300
400
500
600
2.6
2.8
3.0
3.2
3.4
3.6
OUTPUT CURRENT (mA)
OUTPUT CURRENT (mA)
AUX INPUT VOLTAGE (V)
AUX ON-RESISTANCE
vs. TEMPERATURE
240
220
200
180
160
140
120
100
I
= 400mA
OUT
-40 -25 -10
5
20 35 50 65 80
TEMPERATURE (°C)
4
_______________________________________________________________________________________
Network Interface Card Smart Regulator
Typical Operating Characteristics (continued)
(V
, V
= +5V, V
= +3.3V, C
= 1µF, T = +25°C unless otherwise noted.)
MAIN STBY
AUX
OUT A
MAIN OR STANDBY
LINE-TRANSIENT RESPONSE
MAIN OR STANDBY
LOAD-TRANSIENT RESPONSE
MAX1810-11
MAX1810-12
5V
200mA
10mA
V
IN
I
OUT
4.3V
20mV/div
AC-COUPLED
V
OUT
10mV/div
AC-COUPLED
V
OUT
I
= 50mA
OUT
40µs/div
200µs/div
MAIN-T0-STANDBY TRANSITION
WAVEFORM
MAIN OR STANDBY TO AUX
TRANSITION WAVEFORM
MAX1810-13
MAX1810-14
V
IN
V
MAIN
2V/div
MAIN OR STBY
5V
2.4V
3.3V
100mV/div
DC-COUPLED
V
V
OUT
OUT
50mV/div
AC-COUPLED
I
= 250mA
= +5V
I
= 250mA
= +3.3V
OUT
OUT
V
V
STBY
AUX
20ms/div
10ms/div
Pin Description
PIN
1
NAME
STBY
MAIN
OUT
FUNCTION
+5V Standby Input
+5V Main Input
2
3
+3.3V Output. Bypass with a 1µF capacitor to GND.
4
AUX
+3.3V Auxilliary Input
5–8
GND
Ground. Must connect pins 5 through 8 together to ground plane for power dissipation.
_______________________________________________________________________________________
5
Network Interface Card Smart Regulator
Detailed Description
3.3V
OUT
The MAX1810 powers NICs, modem cards, or other
devices that utilize both the main and auxiliary power
supplies in a PCI-compliant system, or other systems
that utilize a standby or sleep-mode power bus. The
MAX1810 supplies a 3.3V, 500mA output from one of
three inputs: a +5V main, a +5V standby, and a +3.3V
auxiliary voltage.
MAIN
STBY
5V
DET
MAIN
REG
5V
DET
STBY
REG
Each input is separately monitored (Figure 1). During
normal operation, the MAIN input powers the fixed
+3.3V output (OUT) through an internal linear regulator.
When MAIN falls below +4.1V or is disconnected, STBY
input powers the output through an internal linear regu-
lator. When the STBY voltage is below +4.1V, an inter-
nal switch connects the +3.3V AUX input to OUT. The
AUX input maintains the output until AUX falls below
+2.5V. Figure 2 shows MAX1810 input transition thresh-
olds. Switchover from one input to another is fast
enough to prevent OUT from falling below +3V under
all cases unless all inputs are below their required volt-
ages. If both MAIN and STBY are above +4.475V, the
MAIN input supplies the output.
AUX
3.3V
DET
CONTROL
LOGIC
GND
Figure 1. Functional Diagram
The MAX1810 prevents reverse current from flowing
from the output to any unbiased or low-voltage input.
MAIN OR STBY
INPUT VOLTAGE
Linear Regulators
The MAIN or STBY inputs generate the +3.3V output
through linear regulators. Each regulator uses an inter-
nal P-channel MOSFET pass transistor. The MAIN or
STBY linear regulator will operate until its input falls
below +4.1V, when it shuts off. Either remaining regula-
tor or AUX input then powers the output. MAIN takes
precedence when both MAIN and STBY are valid.
5.5V
MAIN OR STBY
LDO
GUARANTEED
ON
4.475V
DETECTION
THRESHOLD
RANGE
+3.3V AUX Switch
A 0.18Ω internal switch connects the AUX input to the
output when both MAIN and STBY are below 4.1V and
AUX is greater than 2.5V. When both MAIN and STBY
are below 4.1V or unconnected, and AUX is below 2.5V,
the internal switch does not activate and OUT follows
AUX less one diode drop.
4.1V(TYP)
3.925V
AUX SWITCH
GUARANTEED
ON
Thermal and Overcurrent Protection
Thermal overload protection limits total power dissipa-
tion in the MAX1810. When the junction temperature
(IF AUX > 2.5V)
0
exceeds T = +170°C, the MAX1810 turns off. The
J
device turns back on once its junction temperature
drops by approximately +20°C. A continuous short at
OUT will result in a pulsed output as the thermal over-
load circuitry cycles the device on and off.
Figure 2. MAIN, STBY, and AUX Transition Voltages
6
_______________________________________________________________________________________
Network Interface Card Smart Regulator
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
MAXIMUM CONTINUOUS CURRENT LIMIT
+5V MAIN
INPUT
OUT
MAIN
STBY
AUX
OUT
+3.3V, 500mA
C
*
*
OUT
1.0µF
2.2µF
2.2µF
0.1µF
T = +70°C
A
MAX1810
+5V STBY
INPUT
T = +50°C
A
+3.3V AUX
INPUT
GND
*
T = +80°C
A
T
= +150°C
J(MAX)
3.5
4.0
4.5
5.0
5.5
6.0
*REQUIRED ONLY IF INPUT SUPPLIES DO NOT HAVE NEARBY OUTPUT CAPACITANCE.
SUPPLY VOLTAGE (V)
Figure 3. Power Operating Region: Maximum Output Current
vs. Supply Voltage
Figure 4. Typical Application Circuit
Thermal overload protection safeguards the MAX1810
in the event of fault conditions. For continuous opera-
tion, do not exceed the absolute maximum junction-
Applications Information
Capacitor Selection
The MAX1810 requires a 1µF ceramic bypass capaci-
tor at OUT to maintain regulator stability (Figure 4).
temperature rating of T = +150°C.
J
Both the MAIN and STBY regulators also feature over-
current protection nominally at 900mA. The AUX switch
is not current limited.
When switching between input supplies, the MAX1810
may cause a voltage disturbance on either the MAIN or
STBY input. Limit this disturbance to below the hystere-
sis level (150mV) to guarantee precise switchover. If
the MAIN and STBY input supplies do not have filter
capacitance of their own near the MAX1810 inputs,
then bypass capacitors (2.2µF is recommended) may
be needed at MAIN and STBY. If the input supplies to
MAIN and STBY already have greater than 2.2µF of out-
put capacitance, then no additional capacitance is
required. Place input and output filter capacitors as
close to the device as possible to minimize the effect of
lead inductance of the PC board traces.
Operating Region and Power Dissipation
Maximum power dissipation of the MAX1810 depends
on the thermal resistance of the case and circuit board,
the temperature difference between the die junction
and ambient air, and the rate of airflow. The power dis-
sipation of the device is P = I
(V – V
). The
OUT
OUT
IN
resulting maximum power dissipation is:
P
MAX
= ((T – T ) / (θ + θ ))
J(MAX)
A
JC
CA
where T
is the maximum junction temperature
J(MAX)
(150°C) and T is the ambient temperature, θ is the
A
JC
Chip Information
TRANSISTOR COUNT: 811
thermal resistance from the die junction to the package
case, and θ is the thermal resistance from the case
CA
through the PC board, copper traces, and other materi-
als to the surrounding air (Figure 3). For optimum
power dissipation, use a large ground plane with good
thermal contact to pins 5 through 8. For multilayer
boards, multiple vias are recommended.
PROCESS: BiCMOS
_______________________________________________________________________________________
7
Network Interface Card Smart Regulator
Package Information
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.
8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2000 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
相关型号：
MAX181AEQH-D
ADC, Successive Approximation, 12-Bit, 1 Func, 8 Channel, Parallel, Word Access, PQCC44, PLASTIC, LCC-44
MAXIM
MAX181BCPL+
8-CH 12-BIT SUCCESSIVE APPROXIMATION ADC, PARALLEL ACCESS, PDIP40, PLASTIC, DIP-40
ROCHESTER
MAX181BEQH-D
ADC, Successive Approximation, 12-Bit, 1 Func, 8 Channel, Parallel, Word Access, PQCC44, PLASTIC, LCC-44
MAXIM
©2020 ICPDF网 联系我们和版权申明