MICREL MIC2547-1BTS, MIC2547-1BM, MIC2546-1BM, MIC2546-1BTS, MIC2546-2BM Datasheet

MIC2546/2547 Micrel

MIC2546/2547

Dual Programmable Current Limit Switch

Preliminary Information

General Description

The MIC2546 and MIC2547 are integrated high-side dual
power switches optimized for low loss dc power switching and
other power management applications, including Advanced
Configuration and Power Interface (ACPI). The MIC2546/47
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 current-limit, protects the
switch and the attached device.

The MIC2546/47’s open-drain flag outputs are used to indi­cate current-limiting or thermal shutdown to a local controller.
The MIC2547 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 MIC2547.

The MIC2546 and MIC2547 are available in active-high and
active-low enable versions in 16-pin TSSOP and SOP
packages.

Features

• 2.7V to 5.5V input

• Adjustable current-limit up to 1.5A

• Reverse current flow blocking (no “body diode”)

• 100µA typical on-state supply current per channel

• 2µA typical off-state supply current

• 120mΩ maximum on-resistance

• Open-drain fault flag

• Thermal shutdown

• Thermal shutdown output latch (MIC2547)

• 2ms (slow) turn-on and fast turnoff

• Available with active-high or active-low enable

Applications

• USB power distribution

• PCI Bus Power Switching

• Notebook PC

• ACPI power distribution

• PC card hot swap applications

• Inrush current-limiting

• Ideal for dual supply applications

Typical Application

Typical Advanced Configuration and Power Interface (ACPI) Application

+5V

+3.3V

R

R

R

FLGA

SETA

FLGB

On/Off

On/Off

MIC2546-xBM

ENA
FLGA
GNDA
ILIMA
ENB
FLGB
GNDB
ILIMB

R

SETB

OUTA

INA

OUTA

NC

OUTB

INB

OUTB

NC

0.1µF

Peripheral

33µF

Peripheral

33µF

0.1µF

Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com

June 2000 1 MIC2546/2547

MIC2546/2547 Micrel

Ordering Information

Part Number Enable Latch* Temperature Range Package

MIC2546-1BM Active High –40°C to +85°C 16-pin SOP
MIC2546-1BTS Active High –40°C to +85°C 16-pin TSSOP
MIC2546-2BM Active Low –40°C to +85°C 16-pin SOP
MIC2546-2BTS Active Low –40°C to +85°C 16-pin TSSOP
MIC2547-1BM Active High •–40°C to +85°C 16-pin SOP
MIC2547-1BTS Active High •–40°C to +85°C 16-pin TSSOP
MIC2547-2BM Active Low •–40°C to +85°C 16-pin SOP
MIC2547-2BTS Active Low •–40°C to +85°C 16-pin TSSOP

* Thermal Shutdown Latch

Pin Configuration

MIC2546/2547

LOGIC,

CHARGE

PUMP

LOGIC,

CHARGE

PUMP

(ILIMB) (GND)

(OUTA)

(INA)
(OUTB)

(INB)

OUTA

ENA

NC

FLGA

GNDB

MIC2546/2547

1INA
2
3
4
5
6

16 OUTA

ILIMA

15

GNDA

14

FLGB

13

ENB

12

OUTB

11

(ENA)

(FLGA)
(ILIMA)

(ENB)

(FLGB)

ILIMB

OUTB

7
8

10

NC
INB

9

16-Pin SOP (M)

16-Pin TSSOP (TS)

Pin Description

Pin Number Pin Name Pin Function

1 INA Input A: Output A MOSFET drain. Also supplies internal circuitry.

2, 16 OUTA Switch A (Output): Output A MOSFET source. Pins 2 and 16 must be

3 ENA Enable A (Input): Logic-compatible enable input. Active-high (–1) or active-

4, 10 NC Not internally connected.

5 FLGA Fault Flag A (Output): Active-low, open-drain output. Indicates overcurrent

6, 14 GNDB, GNDA Ground. Both pins must be connected to GND.

7 ILIMB Current Limit Channel B: Sets current-limit threshold using an external

8, 11 OUTB Switch B (Output): Pins 8 and 11 must be externally connected.

9 INB Input B
12 ENB Enable B (Input)
13 FLGB Fault Flag B (Output)
15 ILIMA Current Limit Channel A.

Functional Pinout

externally connected.

low (–2). High input >1.7V typical; low input <1.5V typical. Do not float.
MIC2547 only: Also resets thermal shutdown latch.

or thermal shutdown conditions. MIC2547 only: latched low on thermal
shutdown.

resistor, R

, connected to ground. 154Ω < R

SET

< 2.29kΩ.

SET

MIC2546/2547 2 June 2000

MIC2546/2547 Micrel

Absolute Maximum Ratings (Note 1)

Supply Voltage (V
Output Voltage (V
Output Current (I

Enable Input (VEN) ................................ –0.3V to V

Fault Flag Voltage (V
Fault Flag Current (I

) ..................................................+6.0V

IN

) ...............................................+6.0V

OUT

)...............................Internally Limited

OUT

)...........................................+6.0V

FLG

) ............................................50mA

FLG

IN

+0.3V

Operating Ratings (Note 2)

Supply Voltage (V

Current Limit Set Range.....................................0.1 to 1.5A

Ambient Temperature Range (TA) .............–40°C to +85°C

Package Thermal Resistance

SOP (θJA) ..........................................................120°C/W

TSSOP (θJA) .....................................................100°C/W

) ................................... +2.7V to +5.5V

IN

Storage Temperature (TS) ....................... –65°C to +150°C

Junction Temperature (TJ) .......................Internally Limited

Lead Temperature (soldering 5 sec.) ........................ 260°C

ESD Rating, Note 3 ...................................................... 2kV

Electrical Characteristics

VIN = +5V; TA = 25°C, bold indicates –40°C to +85°C; unless noted
Symbol Parameter Condition Min Typ Max Units

Supply Current Switch off, OUT = open, Note 4 1.5 10 µA

Switch on, OUT = open, Note 4 200 320 µA

V

EN

R

DS(on)

t

ON

t

R

t

OFF

t

F

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. Human body model, 1.5k in series with 100pF.
Note 4. Off is ≤ 0.8V and on is ≥ 2.4V for the MIC2546-1 and MIC2547-1. Off is ≥ 2.4V and on is ≤ 0.8V for the MIC2546-2 and MIC2547-2. The

Note 5. Guaranteed by design, but not production tested.

Note 6. Current limit threshold is determined by:

Enable Input Voltage Enable High, Note 4 2.4 1.7 V

Enable Low, Note 4 1.5 0.8 V

Enable Input Current VEN = V

VEN = V

= 2.4V .01 1 µA

OH(min)

= 0.8V .01 1 µA

OL(max)

Enable Input Capacitance Note 5 1pF
Switch Resistance I
Current Limit Factor, Note 6 I

= 500mA 80 120 mΩ

OUT

= 100mA to 1.5A, V

OUT

= 1.0V to 4.0V, 184 230 276 V

OUT

Note 6

Output Leakage Current Switch off 1 10 µA
Output Turn-On Delay RL = 10Ω, CL = 1µF, Figure 1a and 1b 125ms
Output Turn-On Rise Time RL = 10Ω, CL = 1µF, Figure 1a and 1b 125ms
Output Turnoff Delay RL = 10Ω, CL = 1µF, Figure 1a and 1b 22 µs
Output Turnoff Fall Time RL = 10Ω, CL = 1µF, Figure 1a and 1b 21 µs
Overtemperature Threshold TJ increasing 140 °C
Shutdown TJ decreasing 130 °C
Error Flag Output Resistance VIN = 5V, IL = 10µA415 Ω

VIN = 3.3V, IL = 10µA520 Ω

Error Flag Off Current V

= 5V 0.01 1 µA

FLG

EN Pulse Reset Width MIC2547 Thermal Shutdown Latch 5 µs
VIN to EN Set-Up MIC2547, Note 5 0 µs
Current-Limit Response Time V
Overcurrent FLG Response Time V

enable input has about 200mV of hysteresis.

I

LIMIT

=

= 0V 25 µs

OUT

= VIN/2 to FLG low 5 µs

OUT

230V
R

SET

, where R

is in ohms.

SET

June 2000 3 MIC2546/2547

MIC2546/2547 Micrel

Typical Characteristics

Output On-Resistance

vs. Supply Voltage

100

90

80

70

60

ON-RESISTANCE (mΩ)

50

2.5 3.0 3.5 4.0 4.5 5.0 5.5

SUPPLY VOLTAGE (V)

TA = 27°C

On-State Supply Current

280
240
200
160
120

SUPPLY CURRENT (µA)

vs. Temperature

3.3V

80
40

5.0V

2.7V

0

-40 -20 0 20 40 60 80 100

TEMPERATURE (°C)

Output On-Resistance

120

100

ON-RESISTANCE (mΩ)

vs. Temperature

2.7V

80

60

40

-40 -20 0 20 40 60 80 100

3.3V

5.0V

TEMPERATURE (°C)

Off-State Supply Current

0.8

0.7

0.6

0.5

0.4

0.3

0.2

SUPPLY CURRENT (µA)

0.1

vs. Temperature

RL = 44Ω

3.3V

0

-40 -20 0 20 40 60 80 100

TEMPERATURE (°C)

5.0V

2.7V

On-State Supply Current

vs. Supply Voltage

280
240
200
160
120

80
40

SUPPLY CURRENT (mA)

0

2.5 3.0 3.5 4.0 4.5 5.0 5.5

SUPPLY VOLTAGE (V)

TA = 27°C

Off-State Supply Current

vs. Supply Voltage

0.20

0.18

0.16

0.14

0.12

0.1

0.08

0.06

0.04

SUPPLY CURRENT (µA)

0.02
0

2.5 3.0 3.5 4.0 4.5 5.0 5.5

SUPPLY VOLTAGE (V)

TA = 27°C

Enable Threshold Voltage

vs. Supply Voltage

2.0

1.9

1.8
VEN RISING

1.7

1.6

1.5

1.4

1.3

1.2

ENABLE THRESHOLD (V)

1.1

1.0

2.5 3.0 3.5 4.0 4.5 5.0 5.5

VEN FALLING

SUPPLY VOLTAGE (V)

TA = 27°C

Output Fall Time

2.5

2.0

1.5

1.0

0.5

OUTPUT FALL TIME (µs)

vs. Temperature

RL = 44Ω

2.7V

3.3V

5.0V

0

-40 -20 0 20 40 60 80 100

TEMPERATURE (°C)

Enable Threshold Voltage

2.0

1.8

1.6

1.4

1.2

ENABLE THRESHOLD (V)

1.0

vs. Temperature

VEN RISING

VEN FALLING

-40 -20 0 20 40 60 80 100

TEMPERATURE (°C)

Current Limit

vs. R

2000

1500

1000

500

CURRENT LIMIT (mA)

I

SHORT

0
100 1000 5000

SET

VIN = 5V

I

SET

R

(Ω)

SET

Rise Time

vs. Temperature

7
6
5
4
3
2
1

OUTPUT RISE TIME (ms)

0

-40 -20 0 20 40 60 80 100

2.7V

3.3V

5.0V

RL = 44Ω

TEMPERATURE (°C)

Output Current

2000

1500

1000

I

TH

OUTPUT CURRENT (mA)

vs. Output Voltage

R

= 150

SET

VIN = 5V

R

= 470

500

0

0123456

OUTPUT VOLTAGE (V)

SET

R

= 2.3k

SET

MIC2546/2547 4 June 2000