Micrel MIC2549A-1YTS Programmable current limit high-side switch Datasheet

MIC2545A/2549A
Micrel
MIC2545A/2549A
Programmable Current Limit High-Side Switch
General Description
Features
The MIC2545A and MIC2549A are integrated high-side
power switches optimized for low loss DC power switching
and other power management applications, including Advanced Configuration and Power Interface (ACPI). The
MIC2545A/49A is a cost-effective, highly integrated solution
that requires few external components to satisfy USB and
ACPI requirements.
•
•
•
•
•
•
•
•
•
•
•
Load current management features include a precision,
resistor-programmable output current-limit and a soft-start
circuit, which minimizes inrush current when the switch is
enabled. Thermal shutdown, along with adjustable currentlimit, protects the switch and the attached device.
2.7V to 5.5V input
Adjustable current-limit up to 3A
Reverse current flow blocking
90µA typical on-state supply current
1µA typical off-state supply current
50mΩ maximum on-resistance
Open-drain fault flag
Thermal shutdown
Thermal shutdown output latch (MIC2549A)
2ms (slow) soft-start turn-on, fast turnoff
Available with active-high or active-low enable
Applications
The MIC2545A/49A’s open-drain flag output is used to indicate current-limiting or thermal shutdown to a local controller.
The MIC2549A has an additional internal latch which turns
the output off upon thermal shutdown, providing robust fault
control. The enable signal is compatible with both 3V and 5V
logic, and is also used as the thermal shutdown latch reset for
the MIC2549A.
•
•
•
•
•
•
USB power distribution
PCI Bus Power Switching
Notebook PC
ACPI power distribution
PC card hot swap applications
Inrush current-limiting
The MIC2545A and MIC2549A are available in active-high
and active-low enable versions in 8-pin DIP, SOIC, and
TSSOP packages.
Typical Application
+5V
MIC2545A
10k
On/Off
EN
OUT
FLG
IN
GND
OUT
ILIM
IN
RSET
0.1µF
Peripheral
33µF
Typical Advanced Configuration and Power Interface (ACPI) Application
UL Recognized Component
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
April 2004
1
M9999-041204
MIC2545A/2549A
Micrel
Ordering Information
Part Number
Enable
Latch*
Temperature Range
Package
8-lead SOP
Pb-Free
MIC2545A-1BM
Active High
–40°C to +85°C
MIC2545A-1BN
Active High
–40°C to +85°C
8-pin DIP
MIC2545A-1BTS
Active High
–40°C to +85°C
14-lead TSSOP
MIC2545A-2BM
Active Low
–40°C to +85°C
8-lead SOP
MIC2545A-2BN
Active Low
–40°C to +85°C
8-pin DIP
MIC2545A-2BTS
Active Low
–40°C to +85°C
14-lead TSSOP
MIC2545A-1YM
Active High
–40°C to +85°C
8-lead SOP
MIC2545A-1YN
Active High
–40°C to +85°C
8-pin DIP
MIC2545A-1YTS
Active High
–40°C to +85°C
14-lead TSSOP
MIC2545A-2YM
Active Low
–40°C to +85°C
8-lead SOP
MIC2545A-2YN
Active Low
–40°C to +85°C
8-pin DIP
MIC2545A-2YTS
Active Low
–40°C to +85°C
14-lead TSSOP
MIC2549A-1BM
Active High
–40°C to +85°C
8-lead SOP
MIC2549A-1BN
Active High
–40°C to +85°C
8-pin DIP
MIC2549A-1BTS
Active High
–40°C to +85°C
14-lead TSSOP
MIC2549A-2BM
Active Low
–40°C to +85°C
8-lead SOP
MIC2549A-2BN
Active Low
–40°C to +85°C
8-pin DIP
MIC2549A-2BTS
Active Low
–40°C to +85°C
14-lead TSSOP
MIC2549A-1YM
Active High
–40°C to +85°C
8-lead SOP
MIC2549A-1YN
Active High
–40°C to +85°C
8-pin DIP
MIC2549A-1YTS
Active High
–40°C to +85°C
14-lead TSSOP
MIC2549A-2YM
Active Low
–40°C to +85°C
8-lead SOP
MIC2549A-2YN
Active Low
–40°C to +85°C
8-pin DIP
MIC2549A-2YTS
Active Low
–40°C to +85°C
14-lead TSSOP
Pin Configuration
MIC2545A/2549A
MIC2545A/2549A
EN
1
8
OUT
FLG
2
7
IN
GND
3
6
OUT
ILIM
4
5
IN
EN 1
14 OUT
NC 2
13 NC
FLG 3
12 IN
NC 4
11 NC
10 OUT
GND 5
8-Lead SOP (M)
8-Pin DIP (N)
NC 6
9 NC
ILIM 7
8 IN
MIC2545A/2549A
(EN) 1
(FLG) 2
LOGIC,
CHARGE
PUMP
6,8 (OUT)
14-Lead TSSOP (TS)
5,7 (IN)
(ILIM) 4
M9999-041204
3 (GND)
2
April 2004
MIC2545A/2549A
Micrel
Pin Description
Pin Number
SOP, DIP
Pin Number
TSSOP
Pin Name
1
1
EN
Enable (Input): Logic-compatible enable input (-1 version is active high, -2
version is active low). High input >1.8V typical; low input <1.4V typical.
Do not float.
MIC2549A only: Also resets thermal shutdown latch.
2
3
FLG
Fault Flag (Output): Active-low, open-drain output. Indicates overcurrent or
thermal shutdown.
MIC2549A only: Latched low on thermal shutdown.
3
5
GND
Ground: Supply return.
4
7
ILIM
Current Limit: Sets current limit threshold using an external resistor (RSET)
connected to ground. 76.8Ω < RSET < 459Ω.
5, 7
8, 12
IN
Supply Input: Output MOSFET drain. Also powers internal circuitry. Both IN
pins must be externally connected together.
6, 8
10, 14
OUT
Switch Output: Output MOSFET source. Both OUT pins must be externally
connected together.
2,4,6,9,11,13
NC
April 2004
Pin Function
Not internally connected
3
M9999-041204
MIC2545A/2549A
Micrel
Absolute Maximum Ratings(1)
Operating Ratings(2)
Supply Voltage (VIN) .................................................. +7.0V
Output Voltage (VOUT) ............................................... +7.0V
Output Current (IOUT) ............................... Internally Limited
Enable Input (VEN) ......................................... –0.3V to +7V
Fault Flag Voltage (VFLG) ........................................... +7.0V
Fault Flag Current (IFLG) ............................................ 50mA
Storage Temperature (TS) ....................... –65°C to +150°C
Junction Temperature (TJ) ....................... Internally Limited
Lead Temperature (soldering 5 sec.) ........................ 260°C
ESD Rating(3) .......................................................................... 2004V
Supply Voltage (VIN) ................................... +2.7V to +5.5V
Ambient Temperature Range (TA) ............. –40°C to +85°C
Package Thermal Resistance
PDIP (θJA) ......................................................... 130°C/W
SOIC (θJA) ......................................................... 160°C/W
TSSOP (θJA)(4) .................................................. 100°C/W
Current Limit Set Range(5) ................................. 0.5A to 3A
Electrical Characteristics
VIN = +5V; TA = 25°C, bold indicates –40°C to +85°C; unless noted
Symbol
Parameter
Condition
Supply Current
VEN
Typ
Max
Units
Switch off, OUT =
open(6)
0.75
5
µA
Switch on, OUT =
open(6)
90
125
150
µA
µA
Enable high transition(6)
Enable Input Voltage
Enable low
Enable Input Current
RDS(on)
Min
1.6
V
1.5
0.8
V
VEN = VOH(min) = 2.4V
0.01
1
µA
VEN = VOL(max) = 0.8V
0.01
1
µA
Enable Input Capacitance
Note 7
Switch Resistance
IOUT = 500mA
Current Limit Factor
2.4
transition(6)
1
4V(5)
ILIMIT = 1A to 2.5A, VOUT = 1V to 4V(5)
ILIMIT = 0.5A to 3A, VOUT = 1V to
pF
35
50
mΩ
160
230
300
V
184
230
276
V
1
10
µA
Output Leakage Current
Switch off, VOUT = 0V
tON
Output Turn-On Delay
RL = 10Ω, CL = 1µF, Figures 1a, 1b
1
2
5
ms
tR
Output Turn-On Rise Time
RL = 10Ω, CL = 1µF, Figure 1a, 1b
0.75
1.8
4.9
ms
tOFF
Output Turnoff Delay
RL = 10Ω, CL = 1µF, Figure 1a, 1b
25
µs
tF
Output Turnoff Fall Time
RL = 10Ω, CL = 1µF, Figure 1a, 1b
23
µs
Overtemperature Threshold
Shutdown
TJ increasing
135
°C
TJ decreasing
120
°C
Error Flag Off Current
tSU
VOL
VFLG = 5V
0.01
EN Pulse Reset Width
MIC2549A thermal shutdown
VIN to EN Set-Up
MIC2549A(7),
latch(7)
Figure 1c
Current-Limit Response Time
VOUT = 0V to IOUT = 2A, ISET =
Error Flag Output Resistance
IFLG = 10mA
µA
1
1
µs
0
µs
1A(7)
µs
40
4
Ω
15
Notes:
1. Exceeding the absolute maximum ratings may damage the device.
2. The device is not guaranteed to function outside its operating ratings.
3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
4. Assumes 4 layer PCB is used.
5. Current limit is determined by:
ILIMIT =
230
RSET , where RSET is in ohms, and 230 is typical current limit factor in volts.
6. Off is ≤ 0.8V and on is ≥ 2.4V for the MIC2545A-1 and MIC2549A-1. Off is ≥ 2.4V and on is ≤ 0.8V for the MIC2545A-2 and MIC2549A-2. The
enable input has about 100mV of hysteresis.
7. Guaranteed by design but not production tested.
M9999-041204
4
April 2004
MIC2545A/2549A
Micrel
Test Circuit
VOUT
Device
Under OUT
Test
IOUT
RL
CL
tr
tf
90%
90%
VOUT
10%
10%
Functional Characteristics Test Circuit
Timing Diagrams
VEN
50%
tOFF
tON
90%
VOUT
10%
Figure 1a. MIC2545A/49A-2
VEN
50%
tOFF
tON
90%
VOUT
10%
Figure 1b. MIC2545A/49A-1
VIN
tSU
VEN
Figure 1c. Input-to-Enable Setup Timing
April 2004
5
M9999-041204
MIC2545A/2549A
Micrel
Output Reset
Short-Circuit Fault
EN
VOUT
ILIMIT
Fault Removed
IDC
IOUT
Thermal Shutdown
Reached
FLG
Figure 2a. MIC2549A-2 Timing: Output Is Reset By Toggling EN
EN
Short-Circuit
Fault
Fault
Removed
VOUT
ILIMIT
IDC
IOUT
Thermal Shutdown
Reached
FLG
Figure 2b. MIC2545A-2 Timing
M9999-041204
6
April 2004
MIC2545A/2549A
Micrel
Typical Characteristics
Output On-Resistance
vs. Temperature
40
39
36
35
TA = 27°C
34
33
32
31
3.0 3.5 4.0 4.5 5.0
SUPPLY VOLTAGE (V)
140
45
3.3V
40
2.7V
35
30
25
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
5.5
On-State Supply Current
vs. Temperature
5.0V
3.3V
60
2.7V
40
20
RL = 44Ω
0.4
0.3
5.0V
0.2
3.3V
0.1
2.7V
0
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
0
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
Control Threshold Voltage
vs. Supply Voltage
Control Threshold Voltage
vs. Temperature
TA = 27°C
1.7
1.6
HIGH
1.5
1.4
1.3
1.2
LOW
1.1
1.0
2.5
3.0 3.5 4.0 4.5 5.0
SUPPLY VOLTAGE (V)
5.5
1.0
3.3V
0.8
0.6
5.0V
0.4
0.2
0
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
April 2004
0.04
0.03
0.02
0.01
3.5
HIGH
1.5
LOW
1.4
1.3
1.2
5.5
2.7V
3.0
2.5
3.3V
2.0
5.0V
1.5
1.0
RL = 44Ω
0.5
Output Current
vs. Output Voltage
3500
VIN = 5V
3000
2500
2000
1500
ITH
1000
ILIMIT
500
0
3.0 3.5 4.0 4.5 5.0
SUPPLY VOLTAGE (V)
0
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
OUTPUT CURRENT (mA)
1.2
0.06
0.05
4.0
1.6
5.5
TA = 27°C
Current Limit
vs. Rset
CURRENT LIMIT (mA)
2.7V
0.08
0.07
1.8
1.7
3.0 3.5 4.0 4.5 5.0
SUPPLY VOLTAGE (V)
Rise Time
vs. Temperature
3500
RL = 44Ω
CL = 0µF
20
1.9
Output Fall Time
vs. Temperature
1.4
40
0
2.5
1.1
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
1.8
1.6
60
0.10
0.09
OUTPUT RISE TIME (ms)
CONTROL THRESHOLD (V)
2.0
1.9
1.8
80
Off-State Supply Current
vs. Supply Voltage
SUPPLY CURRENT (µA)
SUPPLY CURRENT (µA)
SUPPLY CURRENT (µA)
120
80
TA = 27°C
100
0
2.5
0.5
100
120
Off-State Supply Current
vs. Temperature
140
THRESHOLD VOLATAGE (V)
5.0V
SUPPLY CURRENT (µA)
38
37
30
2.5
OUTPUT FALL TIME (µs)
On-State Supply Current
vs. Supply Voltage
50
OUTPUT RESISTANCE (mΩ)
OUTPUT RESISTANCE (mΩ)
Output On-Resistance
vs. Supply Voltage
ISHORT
0
150
300
RSET (Ω)
7
450
600
RSET = 92
3000
2500
VIN = 5V
2000
1500
RSET = 230
1000
500
0
RSET = 460
0
1.0 2.0 3.0 4.0 5.0
OUTPUT VOLTAGE (V)
6.0
M9999-041204
MIC2545A/2549A
Micrel
Typical Characteristics cont’d
M9999-041204
1500
1400
1300
1200
Current Limit
vs. Supply Voltage
1200
VIN = 5V
RSET = 230Ω
CURRENT LIMIT (mA)
OUTPUT CURRENT (mA)
Current Limit
vs. Temperature
ITH
1100
1000
ISET
900
800
700
ISHORT
600
500
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
1000
TA = 27°C
RL = 230Ω
ISET
900
800
ISHORT
700
600
2.5
8
ITH
1100
3.0 3.5 4.0 4.5 5.0
SUPPLY VOLTAGE (V)
5.5
April 2004
MIC2545A/2549A
Micrel
Functional Characteristics
VFLG
VEN
(10V/div.) (10V/div.)
VOUT
(2V/div.)
500mA
VIN = 5V
CL = 100 F
RL = 10‰
IOUT
(200mA/div.)
IOUT
(200mA/div.)
Turn-Off Response
VOUT
VFLG
VEN
(2V/div.) (10V/div.) (10V/div.)
Turn-On Response
VIN = 5V
CL = 100µF
RL = 10Ω
500mA
MIC2545A-1
MIC2545A-1
TIME (1ms/div.)
TIME (500µs/div.)
Load Removed
Current-Limit Threshold 1.12A
Short-Circuit Current
820mA (ISHORT)
IOUT
(500mA/div.)
Current-Limit Threshold 1.12A (ITH)
ISET = 1A
IOUT
(500mA/div.)
Short Circuit
VOUT
(5V/div.)
VOUT
(5V/div.)
Thermal Shutdown
C = 5V
RL = 1Ω
Thermal
Shutdown
VIN = 5V
MIC2545A-1
MIC2545A-1
TIME (100ms/div.)
Enable Into Short Circuit
Inrush Current Response
VFLG
VEN
(10V/div.) (10V/div.)
VFLG
VEN
(10V/div.) (10V/div.)
TIME (100ms/div.)
Thermal
Shutdown
MIC2545A-1
TIME (100ms/div.)
April 2004
VIN = 5V
RL = 10Ω
CL = 490µF
CL = 130µF
Short-Circuit Current
820mA
VIN = 5V
RSET = 240Ω
IOUT
(500mA/div.)
VOUT
(5V/div.)
IOUT
(500mA/div.)
Short-Circuit Response
VFLG
VEN
(10V/div.) (10V/div.)
VFLG
VEN
(10V/div.) (10V/div.)
Current-Limit Response
CL = 10µF
MIC2545A-1
TIME (500µs/div.)
9
M9999-041204
MIC2545A/2549A
Micrel
Functional Characteristics cont’d
VEN
VFLG
(5V/div.) (10V/div.)
Thermal Shutdown
(Output Reset by Toggling Enable—MIC2549-1)
Ramped Load to a Short
VOUT
(5V/div.)
Output Reset
Output Latched
IOUT
(500mA/div.)
Thermal
Shutdown
VIN = 5V
CL = 47µF
TIME (100ms/div.)
M9999-041204
10
April 2004
MIC2545A/2549A
Micrel
Block Diagram
EN
IN
OSC.
THERMAL
SHUTDOWN
1.2V
REFERENCE
CHARGE
PUMP
CURRENT
LIMIT
IN
ILIM
RSET
GATE
CONTROL
RESET
THERMAL
SHUTDOWN
LATCH
(MIC2549A)
OUT
OUT
FLG
GND
April 2004
11
M9999-041204
MIC2545A/2549A
Micrel
The current-limit response of the MIC2545A/49A is based on
the type of load that is applied to the output and is defined in
three parts:
Functional Description
The MIC2545A and MIC2549A are high-side N-channel
switches available with active-high or active-low enable inputs. Fault conditions turn off or inhibit turn-on of the output
transistor and activate the open-drain error flag transistor
making it sink current to ground.
1. The first mode of operation is where the device
enters a constant-current mode preventing
further increases in output current. The value of
this current, ILIMIT, is defined by the value of
RSET as explained further in this section.
2. When a short circuit is applied to the output of
an enabled device the output current immediately folds back to a value less than ILIMIT called
ISHORT. This further protects the load and
reduces device power dissipation. Refer to the
“Typical Characteristics: Output Current vs.
Output Voltage” graph for details.
3. When a load is increased, the output current will
proportionally increase up to the current-limit
threshold, ITH, as shown in the “Functional
Characteristics: Current-Limit Response” graph.
The device in this case will supply current
slightly higher than the current-limit set point
defined by RSET. As the load is increased
further the current folds back to ILIMIT.
The nominal current-limit value, ILIMIT, is set with an external
resistor between ILIM (pin 4) and GND (pin 3). For a desired
current-limit, the value of the external set resistor is given by:
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 MIC2545A/49A avoids
undesirable current flow from OUT to IN. Both IN pins must
be connected together, and both OUT pins must be connected together.
Thermal Shutdown
Thermal shutdown shuts off the output MOSFET and signals
the fault flag if the die temperature exceeds 135°C. 10°C of
hysteresis prevents the switch from turning on until the die
temperature drops to 125°C. Overtemperature detection
functions only when the switch is enabled.
The MIC2549A features an internal latch which causes the
part to remain off after thermal shutdown until a reset pulse
is provided via the enable pin (pin 1). While in current-limit, the
thermal shutdown latch prevents on/off cycling of the output.
Refer to Figure 2 for timing diagram. The flag remains low
until reset.
 230 
RSET = 

 ILIMIT 
where:
76.8Ω < RSET < 459Ω
For example, to set a 1A nominal current-limit, RSET is
calculated as:
Enable Input
EN must be driven logic high or logic low, or be pulled high or
low for a clearly defined input. Floating the input may cause
unpredictable operation. EN should not be allowed to go
negative with respect to GND.
 230 

 = 230Ω
 1A 
Refer to the “Typical Characteristics: Current-Limit vs RSET”
graph for more details.
Current-Limit Operation
The current limit is user adjustable with an external set
resistor. Current limiting in the range of 500mA to 3A is
available with a set point accuracy of better than ±30% (±20%
for ISET 1 to 2.5A). The current-limit circuit prevents damage
to the output MOSFET and external load.
Current through RSET increases with output current. The
voltage across RSET could be monitored with a high impedance comparator to provide an indication of output current.
RSET should be between 76.8Ω and 459Ω (1% resister
value).
Fault Flag
FLG is an N-channel, open-drain MOSFET output. The faultflag is active (low) for current-limit or thermal shutdown
conditions. The flag output MOSFET is capable of sinking a
10mA load to typically 100mV above ground. For applications
with VIN ≤ 3.6V, it is recommended that flag current be limited
to 5mA or less.
M9999-041204
12
April 2004
MIC2545A/2549A
Micrel
Applications Information
TJ = junction temperature
Supply Filtering
TA = ambient temperature
θJA = is the thermal resistance of the package
A 0.1µF to 1µF bypass capacitor from IN to GND, located
near the MIC2545A and MIC2549A, 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.
Transient Overcurrent Filter
The inrush current from the connection of a heavy capacitive
load may cause the fault flag to fall for 10µs to 200µs while the
switch is in a constant-current mode, charging the capacitance.
Input transients must not exceed the absolute maximum
supply voltage (VIN (max) = 6V) even for a short duration.
Adding an optional series resistor-capacitor (RSET2) in parallel with RSET, as shown in Figure 4, allows the transient
current-limit to be set to a different value than steady state. A
typical USB hot-plug inrush is 2A to 3A for 10µs to 20µs. If
RSET is 435Ω (530mA), an RSET2 of 88Ω (2.5A) and CSET of
1µF (RC ≈ 90µs) allows transient surge of 3A to pass for 90µs
without tripping the overcurrent flag (FLG).
USB Power Distribution
4.0V to 5.5V
MIC2549A-1BM
1
EN
2
3
4
OUT
FLG
IN
GND
OUT
ILIM
IN
8
7
0.1µF to 1µF
6
5
RSET
The MIC2545A is ideal for meeting USB power distribution
requirements. Figure 7 depicts a USB Host application. RSET
should be set to a value providing a current-limit >500mA.
The accurate current-limit of the MIC2545A will reduce power
supply current requirements. Also, fast reaction to short
circuit faults prevent voltage droop in mobile PC applications.
Figure 3. Supply Bypassing
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 and junction temperature are found below.
Printed Circuit Board Hot-Plug
The MIC2545A/49A is an ideal inrush current-limiter suitable
for hot-plug applications. Due to the integrated charge pump,
the MIC2545A/49A 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 5 shows how the MIC2545A may be used in
a hot-plug application.
Calculation of power dissipation can be accomplished by the
following equation:
PD = RDS(on) × (IOUT)2
To relate this to junction temperature, the following equation
can be used:
TJ = PD × θJA + TA
where:
Ferrite
Bead
5V
(+)
10k
4.7µF
(–)
VBUS
D+
IN
D–
3.3V USB Controller
V+
OUT
GND
VBUS
D+
MIC5203-3.3
LDO Regulator
1.0
µF
ON/OFF
EN
OVERCURRENT
GND
1.5k
2%
MIC2545A-2
0.1µF
FLG
IN
GND
OUT
ILIM
IN
D–
GND
0.1µF
D+
D–
0.01µF
120µF
OUT
Downstream
USB
Port 1
4.75V min.
500mA max.
GND
RSET
RSET(2)
CSET
Bold lines indicate
0.1" wide, 1-oz. copper
high-current traces.
(optional)
Figure 4. USB Host Application
April 2004
13
M9999-041204
MIC2545A/2549A
Micrel
MIC2545A-2
1
VCC
2
to "Hot"
Receptacle
0.1
µF
3
4
EN
OUT
FLG
IN
GND
OUT
ILIM
IN
8
7
Backend
Function
6
5
CBULK
0.1µF
GND
Adaptor Card
Figure 5. Hot-Plug Application
M9999-041204
14
April 2004
MIC2545A/2549A
Micrel
Package Information
PIN 1
DIMENSIONS:
INCH (MM)
0.380 (9.65)
0.370 (9.40)
0.255 (6.48)
0.245 (6.22)
0.135 (3.43)
0.125 (3.18)
0.300 (7.62)
0.013 (0.330)
0.010 (0.254)
0.018 (0.57)
0.130 (3.30)
0.100 (2.54)
0.380 (9.65)
0.320 (8.13)
0.0375 (0.952)
8-Pin DIP (N)
0.026 (0.65)
MAX)
PIN 1
0.157 (3.99)
0.150 (3.81)
DIMENSIONS:
INCHES (MM)
0.050 (1.27)
TYP
0.064 (1.63)
0.045 (1.14)
0.197 (5.0)
0.189 (4.8)
0.020 (0.51)
0.013 (0.33)
0.0098 (0.249)
0.0040 (0.102)
0°–8°
SEATING
PLANE
45°
0.010 (0.25)
0.007 (0.18)
0.050 (1.27)
0.016 (0.40)
0.244 (6.20)
0.228 (5.79)
8-Pin SOIC (M)
April 2004
15
M9999-041204
MIC2545A/2549A
Micrel
4.50 (0.177)
6.4 BSC (0.252)
4.30 (0.169)
DIMENSIONS:
MM (INCH)
0.30 (0.012)
0.19 (0.007)
5.10 (0.200)
4.90 (0.193)
0.20 (0.008)
0.09 (0.003)
1.10 MAX (0.043)
0.65 BSC
(0.026)
1.00 (0.039) REF
8°
0°
0.15 (0.006)
0.05 (0.002)
0.70 (0.028)
0.50 (0.020)
14-Pin TSSOP (TS)
MICREL INC. 1849 FORTUNE DRIVE
TEL
+ 1 (408) 944-0800
FAX
SAN JOSE, CA 95131
+ 1 (408) 474-1000
WEB
USA
http://www.micrel.com
This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or
other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc.
© 2004 Micrel Incorporated
M9999-041204
16
April 2004