Micrel MIC2075 Single-channel power distribution switch mm8â® Datasheet

MIC2025/2075
Micrel, Inc.
MIC2025/2075
Single-Channel Power Distribution Switch MM8®
General Description
Features
The MIC2025 and MIC2075 are high-side MOSFET switches
optimized for general-purpose power distribution requiring
circuit protection.
•
•
•
•
•
The MIC2025/75 are internally current limited and have
thermal shutdown that protects the device and load. The
MIC2075 offers “smart” thermal shutdown that reduces current consumption in fault modes. When a thermal shutdown
fault occurs, the output is latched off until the faulty load is
removed. Removing the load or toggling the enable input will
reset the device output.
•
•
•
•
•
•
•
•
Both devices employ soft-start circuitry that minimizes inrush
current in applications where highly capacitive loads are employed. A fault status output flag is provided that is asserted
during overcurrent and thermal shutdown conditions.
The MIC2025/75 is available in the MM8® 8‑lead MSOP
and 8‑lead SOP.
140mΩ maximum on-resistance
2.7V to 5.5V operating range
500mA minimum continuous output current
Short-circuit protection with thermal shutdown
Fault status flag with 3ms filter eliminates false assertions
Undervoltage lockout
Reverse current flow blocking (no “body diode”)
Circuit breaker mode (MIC2075) reduces power
consumption
Logic-compatible input
Soft-start circuit
Low quiescent current
Pin-compatible with MIC2525
UL File # E179633
Applications
•
•
•
•
•
•
USB peripherals
General purpose power switching
ACPI power distribution
Notebook PCs
PDAs
PC card hot swap
Typical Application
VCC
2.7V to 5.5V
10k
Logic Controller
VIN
1µF
MIC2025/75
ON/OFF
OVERCURRENT
GND
EN
OUT
FLG
IN
GND
OUT
NC
Load
NC
0.1µF
UL Recognized Component
MM8 is a registered trademark of Micrel, Inc.
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
June 2010
1
MIC2025/2075
MIC2025/2075
Micrel, Inc.
Ordering Information
Part Number
Enable
Temperature Range
Package
Active High
-40°C to +85°C
8-Lead SOIC
Standard
Pb-Free
MIC2025-1BM
MIC2025-1YM
MIC2025-2BM
MIC2025-2YM
Active Low
-40°C to +85°C
8-Lead SOIC
MIC2025-1BMM
MIC2025-1YMM
Active High
-40°C to +85°C
8-Pin MSOP
MIC2025-2BMM
MIC2025-2YMM
Active Low
-40°C to +85°C
8-Pin MSOP
MIC2075-1BM
MIC2075-1YM
Active High
-40°C to +85°C
8-Lead SOIC
MIC2075-2BM
MIC2075-2YM
Active Low
-40°C to +85°C
8-Lead SOIC
MIC2075-1BMM
MIC2075-1YMM
Active High
-40°C to +85°C
8-Pin MSOP
MIC2075-2BMM
MIC2075-2YMM
Active Low
-40°C to +85°C
8-Pin MSOP
Pin Configuration
MIC2025/75
EN 1
8
OUT
FLG 2
7
IN
GND 3
6
OUT
NC 4
5
NC
8-Lead SOIC (BM)
8-Lead MSOP (BMM)
Pin Description
Pin Number
Pin Name
Pin Function
1
EN
Switch Enable (Input): Active-high (-1) or active-low (-2).
2
FLG
Fault Flag (Output): Active-low, open-drain output. Indicates overcurrent or
thermal shutdown conditions. Overcurrent condition must exceed tD in order
to assert FLG.
3
GND
Ground
4
NC
not internally connected
5
NC
not internally connected
6, 8
OUT
7
IN
MIC2025/2075
Supply (Output): Pins must be connected together.
Supply Voltage (Input).
2
June 2010
MIC2025/2075
Micrel, Inc.
Absolute Maximum Ratings (Note 1)
Operating Ratings (Note 2)
Supply Voltage (VIN)...........................................–0.3V to 6V
Fault Flag Voltage (VFLG)............................................... +6V
Fault Flag Current (IFLG)............................................. 25mA
Output Voltage (VOUT).................................................... +6V
Output Current (IOUT)................................ Internally Limited
Enable Input (IEN)...................................... –0.3V to VIN +3V
Storage Temperature (TS)......................... –65°C to +150°C
ESD Rating, Note 3
Supply Voltage (VIN) . .................................. +2.7V to +5.5V
Ambient Temperature (TA)........................... –40°C to +85°C
Junction Temperature (TJ)......................... Internally Limited
Thermal Resistance
SOP (θJA)........................................................... 160°C/W
MSOP(θJA)......................................................... 206°C/W
Electrical Characteristics
VIN = +5V; TA = 25°C, bold values indicate –40°C ≤ TA ≤ +85°C; unless noted
Symbol
Parameter
Condition
Min
Typ
Max
Units
IDD
Supply Current
MIC20x5-1, VEN ≤ 0.8V, (switch off), OUT = open
0.75
5
µA
MIC20x5-2, VEN ≥ 2.4V, (switch off),
OUT = open
0.75
5
µA
MIC20x5-1, VEN ≥ 2.4V, (switch on),
OUT = open
160
µA
MIC20x5-2, VEN ≤ 0.8V, (switch on),
OUT = open
160
µA
low-to-high transition
2.1
2.4
V
high-to-low transition
1.9
V
200
mV
1
µA
VEN
Enable Input Voltage
0.8
Enable Input Hysteresis
IEN
RDS(on)
Enable Input Current
1
90
140
mΩ
VIN = 3.3V, IOUT = 500mA
100
160
mΩ
10
µA
MIC2075
(during thermal shutdown state)
50
µA
OFF Current in Latched
Thermal Shutdown
Output Turn-On Delay
tR
Output Turn-On Rise Time
tF
Output Turnoff Fall Time
ILIMIT
0.01
Switch Resistance
Output Leakage Current
tOFF
–1
Control Input Capacitance
tON
VEN = 0V to 5.5V
Output Turnoff Delay
Short-Circuit Output Current
Current-Limit Threshold
VIN = 5V, IOUT = 500mA
MIC2025/2075 (output off)
RL = 10Ω, CL = 1µF, see “Timing Diagrams”
RL = 10Ω, CL = 1µF, see “Timing Diagrams”
1
2.5
6
ms
0.5
2.3
5.9
ms
50
100
µs
50
100
µs
RL = 10Ω, CL = 1µF, see “Timing Diagrams”
RL = 10Ω, CL = 1µF, see “Timing Diagrams”
VOUT = 0V, enabled into short-circuit.
ramped load applied to output, Note 4
pF
0.5
0.7
1.25
A
0.60
0.85
1.25
A
Short-Circuit Response Time
VOUT = 0V to IOUT = ILIMIT (Short applied to output)
24
µs
tD
Overcurrent Flag Response
Delay
VIN = 5V, apply VOUT = 0V until FLG low
3
7
ms
Undervoltage Lockout
Threshold
VIN rising
June 2010
VIN = 3.3V, apply VOUT = 0V until FLG low
VIN falling
3
1.5
1.5
3
8
ms
2.2
2.5
2.7
V
2.0
2.3
2.5
V
MIC2025/2075
MIC2025/2075
Symbol
Micrel, Inc.
Parameter
Condition
Error Flag Output
Resistance
IL = 10mA, VIN = 5V
Typ
Max
Units
8
25
Ω
11
40
Ω
VFLAG = 5V
10
µA
140
°C
120
°C
IL = 10mA, VIN = 3.3V
Error Flag Off Current
Overtemperature Threshold
Min
TJ increasing
TJ decreasing
Note 1.
Exceeding the absolute maximum rating may damage the device.
Note 2.
The device is not guaranteed to function outside its operating rating.
Note 3.
Devices are ESD sensitive. Handling precautions recommended.
Note 4.
See “Functional Characteristics: Current-Limit Response” graph.
Test Circuit
IOUT
Device
Under OUT
Test
VOUT
RL
CL
Timing Diagrams
tR
tF
90%
VOUT
90%
10%
10%
Output Rise and Fall Times
VE N
50%
tO F F
tON
90%
VOUT
10%
Active-Low Switch Delay Times (MIC20x5-2)
VE N
50%
tO F F
tON
VOUT
90%
10%
Active-High Switch Delay Times (MIC20x5-1)
MIC2025/2075
4
June 2010
MIC2025/2075
Micrel, Inc.
S upply On-C urrent
vs . T emperature
180
160
160
100
80
3.3V
60
40
20
0
-40 -20
0 20 40 60
TEMPERATURE (°C)
100
5V
80
60
40
I OUT = 500mA
0 20 40 60
TEMPERATURE (°C)
+25°C
50
+85°C
V IN = 5V
R L =10Ω
C L =1µF
0
-40 -20
80 100
On-R es is tanc e
vs . Input V oltage
5.0
0
20 40 60
TEMPERATURE (°C)
100
+25°C
50
-40°C
+85°C
3.0
+25°C
-40°C
2.0
1.0
R L =10Ω
C L =1µF
I OUT = 500mA
200
0
-40 -20
0 20 40 60
TEMPERATURE (°C)
80 100
S hort-C irc uit C urrent-L imit
vs . Input V oltage
+25°C
700
600
500
+85°C
-40°C
400
300
200
100
0
2.5
June 2010
3.0 3.5 4.0 4.5
INPUT VOLTAGE (V)
5.0
5.5
3.0 3.5 4.0 4.5
INPUT VOLTAGE (V)
5.0
0
2.5
5.5
C urrent-L imit T hres hold
vs . T emperature
1000
2.5
V IN = 3.3V
800
V IN = 5V
600
400
200
0
-40 -20
0 20 40 60
TEMPERATURE (°C)
80 100
1200
1100
1000
900
800
700
600 +85°C
+25°C
-40°C
500
400
300
200
100
0
2.5 3.0 3.5 4.0 4.5 5.0
INPUT VOLTAGE (V)
5.0
5.5
E nable T hres hold
vs . T emperature
V E N R IS ING
1.5
V E N F ALLING
1.0
0.5
V IN = 5V
0
-40 -20
C urrent-L imit T hres hold
vs . Input V oltage
5
3.0 3.5 4.0 4.5
INPUT VOLTAGE (V)
2.0
ENABLE THRESHOLD (V)
400
V IN = 5V
1200
CURRENT LIMIT THRESHOLD (mA)
CURRENT LIMIT (mA)
V IN = 3.3V
600
800
0
2.5
5.5
S hort-C irc uit C urrent-L imit
vs . T emperature
800
CURRENT LIMIT (mA)
5.0
CURRENT LIMIT THRESHOLD (mA)
1000
3.0 3.5 4.0 4.5
INPUT VOLTAGE (V)
2.5
0
20 40 60
TEMPERATURE (°C)
80 100
E nable T hres hold
vs . Input V oltage
2.0
ENABLE THRESHOLD (V)
0
2.5
80 100
T urn-O n R is e T ime
vs . Input V oltage
4.0
+85°C
RISE TIME (ms)
RESISTANCE (mΩ)
100
2
1
150
-40°C
3
20
200
150
V IN = 3.3V
4
3.3V
0
-40 -20
80 100
S upply On-C urrent
vs . Input V oltage
200
120
RISE TIME (ms)
ON-RESISTANCE (mΩ)
CURRENT (µA)
5V
120
T urn-O n R is e T ime
vs . T emperature
5
140
140
CURRENT (µA)
On-R es is tanc e
vs . T emperature
5.5
V E N R IS ING
1.5
1.0
0.5
0
2.5
V E N F ALLING
T A = 25°C
3.0 3.5 4.0 4.5
INPUT VOLTAGE (V)
5.0
5.5
MIC2025/2075
MIC2025/2075
4
DELAY TIME (ms)
5
V IN = 3.3V
4
V IN = 5V
3
2
1
0
-40 -20
0
20 40 60
TEMPERATURE (°C)
MIC2025/2075
80 100
3
F lag Delay
vs . Input V oltage
3.0
2.5
+25°C
2
-40°C
1
0
2.5
UV L O T hres hold
vs . T emperature
V IN R IS ING
+85°C
UVLO THRESHOLD (V)
F lag Delay
vs . T emperature
DELAY TIME (ms)
5
Micrel, Inc.
3.0 3.5 4.0 4.5
INPUT VOLTAGE (V)
6
5.0
5.5
2.0
V IN F ALLING
1.5
1.0
0.5
0
-40 -20
0
20 40 60
TEMPERATURE (°C)
80 100
June 2010
MIC2025/2075
Micrel, Inc.
Functional Characteristics
June 2010
7
MIC2025/2075
MIC2025/2075
MIC2025/2075
Micrel, Inc.
8
June 2010
MIC2025/2075
Micrel, Inc.
Block Diagram
EN
OSC.
THERMAL
SHUTDOWN
1.2V
REFERENCE
UVLO
CHARGE
PUMP
GATE
CONTROL
IN
CURRENT
LIMIT
FLAG
RESPONSE
DELAY
OUT
FLG
GND
Functional Description
Power Dissipation
The device’s junction temperature depends on several factors such as the load, PCB layout, ambient temperature
and package type. Equations that can be used to calculate
power dissipation of each channel and junction temperature
are found below.
Input and Output
IN is the power supply connection to the logic circuitry and
the drain of the output MOSFET. OUT is the source of the
output MOSFET. In a typical circuit, current flows from IN to
OUT toward the load. If VOUT is greater than VIN, current will
flow from OUT to IN since the switch is bidirectional when
enabled. The output MOSFET and driver circuitry are also
designed to allow the MOSFET source to be externally forced
to a higher voltage than the drain (VOUT > VIN) when the
switch is disabled. In this situation, the MIC2025/75 avoids
undesirable current flow from OUT to IN.
PD = RDS(on) × IOUT2
Total power dissipation of the device will be the summation of
PD for both channels. To relate this to junction temperature,
the following equation can be used:
TJ = PD × θJA + TA
where:
Thermal Shutdown
Thermal shutdown is employed to protect the device from
damage should the die temperature exceed safe margins
due mainly to short circuit faults. Each channel employs its
own thermal sensor. Thermal shutdown shuts off the output
MOSFET and asserts the FLG output if the die temperature
reaches 140°C. The MIC2025 will automatically reset its output
should the die temperature cool down to 120°C. The MIC2025
output and FLG signal will continue to cycle on and off until
the device is disabled or the fault is removed. Figure 2 depicts
typical timing. If the MIC2075 goes into thermal shutdown, its
output will latch off and a pull-up current source is activated.
This allows the output latch to automatically reset when the
load (such as a USB device) is removed. The output can also
be reset by toggling EN. Refer to Figure 1 for details.
TJ = junction temperature
TA = ambient temperature
θJA = is the thermal resistance of the package
Current Sensing and Limiting
The current-limit threshold is preset internally. The preset
level prevents damage to the device and external load but
still allows a minimum current of 500mA to be delivered to
the load.
The current-limit circuit senses a portion of the output MOSFET
switch current. The current-sense resistor shown in the block
diagram is virtual and has no voltage drop. The reaction to
an overcurrent condition varies with three scenarios:
Switch Enabled into Short-Circuit
If a switch is enabled into a heavy load or short-circuit, the
switch immediately enters into a constant-current mode,
reducing the output voltage. The FLG signal is asserted
indicating an overcurrent condition. See the Short-Circuit
Response graph under Functional Characteristics.
Depending on PCB layout, package, ambient temperature,
etc., it may take several hundred milliseconds from the incidence of the fault to the output MOSFET being shut off.
The worst-case scenario of thermal shutdown is that of a
short-circuit fault and is shown in the in the “Function Characteristics: Thermal Shutdown Response” graph.
June 2010
9
MIC2025/2075
MIC2025/2075
Micrel, Inc.
Fault Flag
The FLG signal is an N-channel open-drain MOSFET output.
FLG is asserted (active-low) when either an overcurrent
or thermal shutdown condition occurs. In the case where
an overcurrent condition occurs, FLG will be asserted only
after the flag response delay time, tD, has elapsed. This
ensures that FLG is asserted only upon valid overcurrent
conditions and that erroneous error reporting is eliminated.
For example, false overcurrent conditions can occur during
hot-plug events when a highly capacitive load is connected
and causes a high transient inrush current that exceeds the
current-limit threshold. The FLG response delay time tD is
typically 3ms.
Short-Circuit Applied to Enabled Output
When a heavy load or short-circuit is applied, a large transient
current may flow until the current-limit circuitry responds. Once
this occurs the device limits current to less than the short-circuit current limit specification. See the Short-Circuit Transient
Response graph under Functional Characteristics.
Current-Limit Response—Ramped Load
The MIC2025/75 current-limit profile exhibits a small foldback
effect of about 200mA. Once this current-limit threshold is
exceeded the device switches into a constant current mode.
It is important to note that the device will supply current until
the current-limit threshold is exceeded. See the Current-Limit
Response graph under Functional Characteristics.
VE N
Undervoltage Lockout
Undervoltage lockout (UVLO) prevents the output MOSFET from turning on until VIN exceeds approximately 2.5V.
Undervoltage detection functions only when the switch is
enabled.
Short-Circuit Faul
t
Load Removed
(Output Reset)
VOUT
ILIMIT
IDC
IOUT
Thermal Shutdown
Reached
VF L G
tD
Figure 1. MIC2075-2 Timing: Output Reset by Removing Load
VE N
Short-Circuit Faul
t
Load/Fault
Removed
VOUT
ILIMIT
IDC
IOUT
Thermal Shutdown
Reached
VF L G
tD
Figure 2. MIC2025-2 Timing
MIC2025/2075
10
June 2010
MIC2025/2075
Micrel, Inc.
Applications Information
Universal Serial Bus (USB) Power Distribution
The MIC2025/75 is ideally suited for USB (Universal Serial
Bus) power distribution applications. The USB specification
defines power distribution for USB host systems such as
PCs and USB hubs. Hubs can either be self-powered or
bus-powered (that is, powered from the bus). Figure 5 below
shows a typical USB Host application that may be suited for
mobile PC applications employing USB. The requirements
for USB host systems is that the port must supply a minimum
of 500mA at an output voltage of 5V ±5%. In addition, the
output power delivered must be limited to below 25VA. Upon
an overcurrent condition, the host must also be notified. To
support hot-plug events, the hub must have a minimum of
120µF of bulk capacitance, preferably low-ESR electrolytic
or tantulum. Refer to Application Note 17 for more details on
designing compliant USB hub and host systems.
Supply Filtering
A 0.1µF to 1µF bypass capacitor positioned close to VIN and
GND of the device is strongly recommended to control supply transients. Without a bypass capacitor, an output short
may cause sufficient ringing on the input (from supply lead
inductance) to damage internal control circuitry.
Printed Circuit Board Hot-Plug
The MIC2025/75 are ideal inrush current-limiters suitable for
hot-plug applications. Due to the integrated charge pump,
the MIC2025/75 presents a high impedance when off and
slowly becomes a low impedance as it turns on. This “softstart” feature effectively isolates power supplies from highly
capacitive loads by reducing inrush current during hot-plug
events. Figure 3 shows how the MIC2075 may be used in a
hot-plug application.
For bus-powered hubs, USB requires that each downstream
port be switched on or off under control by the host. Up to four
downstream ports each capable of supplying 100mA at 4.4V
minimum are allowed. In addition, to reduce voltage droop on
the upstream VBUS, soft-start is necessary. Although the hub
can consume up to 500mA from the upstream bus the hub
must consume only 100mA max at start-up, until it enumerates with the host prior to requesting more power. The same
requirements apply for bus-powered peripherals that have no
downstream ports. Figure 6 shows a bus-powered hub.
In cases of extremely large capacitive loads (>400µF), the
length of the transient due to inrush current may exceed the
delay provided by the integrated filter. Since this inrush current exceeds the current-limit delay specification, FLG will
be asserted during this time. To prevent the logic controller
from responding to FLG being asserted, an external RC filter,
as shown in Figure 4, can be used to filter out transient FLG
assertion. The value of the RC time constant will be selected
to match the length of the transient.
MIC2025-2
VC C
0.1
µF
to "Hot"
Receptacle
1
EN
2
OUT
8
FLG
IN
7
3
GND
OUT
6
4
NC
NC
5
Backend
Function
CBULK
GND
Adaptor Card
Figure 3. Hot Plug Application
V+
Logic Controller
OVERCURRENT
10k
R
C
MIC2025
1
EN
OUT
8
2
3
FLG
IN
7
GND
OUT
6
4
NC
NC
5
Figure 4. Transient Filter
June 2010
11
MIC2025/2075
MIC2025/2075
Micrel, Inc.
VC C
5.0V
4.50V to 5.25V
Upstream VB U S
100mA max.
VB U S
10k
3.3V
MIC5203-3.3
IN
D+
1µF
D–
3.3V USB Controller
VIN
OUT
1µF
GND
GND
Ferrite
Beads
MIC2025/75
ON/OFF
EN
OVERCURRENT
GND
VB U S
OUT
FLG
IN
GND
OUT
D+
0.01µF
120µF
GND
NC
NC
D–
USB
Port
0.1µF
Data
Data
Figure 5 USB Host Application
1.5k
3.3V
USB Upstream
Connector
MIC5203-3.3
(LDO)
VB U S
IN
D+
D–
OUT
USB Logic Controller
VIN
GND
GND
0.1µF
0.1µF
Ferrite
Beads
MIC2025/75
EN
ON/OFF
OVERCURRENT
GND
FLG
IN
GND
OUT
NC
1.5K
VB U S
OUT
D+
120µF
0.01µF
D–
GND
NC
USB Downstream
Connector
(Up to four
ganaged ports)
0.1µF
Data
Data
Figure 6. USB Bus-Powered Hub
MIC2025/2075
12
June 2010
MIC2025/2075
Micrel, Inc.
Package Information
8-Lead SOIC (M)
MM8™ 8-Pin MSOP (MM)
June 2010
13
MIC2025/2075
MIC2025/2075
Micrel, Inc.
MICREL INC.
2180 FORTUNE DRIVE SAN JOSE, CA 95131
USA
tel + 1 (408) 944-0800 fax + 1 (408) 474-1000 web http://www.micrel.com
This information furnished by Micrel in this data sheet is believed to be accurate and reliable. However no responsibility is assumed by Micrel for its use.
Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can
reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into
the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser's
use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser's own risk and Purchaser agrees to fully indemnify
Micrel for any damages resulting from such use or sale.
© 2004 Micrel Incorporated
MIC2025/2075
14
June 2010
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