Datasheet MIC2505-2BN, MIC2505BM, MIC2505BN, MIC2506BM, MIC2505-2BM Datasheet (MICREL)

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Page 1

MIC2505/2506 Micrel

MIC2505/2506

Single 2A / Dual 1A / High-Side Switches

General Description

The MIC2505, MIC2505-1, MIC2505-2, and MIC2506 are single and dual integrated high-side power switches that consist of TTL compatible control/enable inputs, a charge pump, and protected N-channel MOSFETs. The MIC2505/6 family can be used instead of separate high-side drivers and MOSFETs in many low-voltage applications.

The MIC2505/6 family controls voltages ranging from 2.7V to

7.5V. The MIC2505-series can deliver at least 2A continuous current while the MIC2506 can deliver at least 1A continuous current from each output. A slow turn-on feature prevents high inrush current when switching capacitive loads. The internal control circuitry is powered from the same 2.7V to

7.5V. Within the device’s input range, outputs can be forced higher than the input voltage when disabled.

Multipurpose open-drain fault flag outputs indicate overcurrent limiting, open-load detection (except MIC2505-1 and -2 versions), thermal shutdown, or undervoltage lockout for each channel.

Overcurrent limiting is internally fixed and requires no external components.

Open-load detection is active when the switch is off. When off, a normal load pulls the output pin low. If the load is open, an optional, external, high-value resistor pulls the output pin high, triggering the fault flag. MIC2505-1 and -2 versions are tailored to Universal Serial Bus (USB) applications and do not include open-load detection.

Thermal shutdown turns off the output if the die temperature exceeds approximately 135°C. If enabled, the switch automatically restarts when the temperature falls 10°C.

Undervoltage lockout (UVLO) shuts off the output if the supply drops below 2.3V typical and reenables the output when the supply exceeds 2.5V typical.

Features

• Low MOSFET on resistance to 2.7V 30mΩ typical at 5V (MIC2505-series) 35mΩ typical at 3.3V (MIC2505-series) 75mΩ typical at 5V (each MIC2506 output) 80mΩ typical at 3.3V (each MIC2506 output)

• 2.7V to 7.5V input

• 110µA typical on-state supply current

•1µA typical off-state supply current

• Output can be forced higher than input (off-state)

• Current limit

• Thermal shutdown

• 2.5V undervoltage lockout (UVLO)

• Open-load detection (MIC2505BN/M and MIC2506BN/M only)

• Open-drain fault flag

• 5ms (slow) turn-on and fast turnoff

• Logic-level control/enable input

Applications

• USB Power Distribution

• 3.3V and 5V power management

• PC Card card inrush limiting switch

• Hot plug-in power supplies

• Battery-charger circuits

Typical Applications

2.7V to 7.5V

Resistors

(100k each)

A ON

A OFF

FAULT B

B ON

B OFF

Pull-up

MIC2506BM

CTL A OUT A

FLG A

FLG B GND

CTL B OUT B

OFF

Pull-up

Resistor

(100k)

MIC2505BM

CTL OUT

FLG

GND OUT

GATE IN

Optional Output Delay Capacitor

INFAULT

0.1µF

100k

Optional

Open Load Detect Resistor (MIC2505BN or

MIC2505BM

only)

Load

Single and Dual Switch/Circuit Breakers with Open-Load Detection and Fault Output

April 1998 1 MIC2505/2506

2.7V to 7.5V

INFAULT A

0.1µF

100k 100k

Optional Open Load Detect Resistors

Load B

Load A

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MIC2505/2506 Micrel

Ordering Information

Part Number Control/Enable Open-Load Detect Temperature Range Package Single-Switch

MIC2505BM Active-High Yes –40°C to +85°C 8-pin SOIC MIC2505BN Active-High Yes –40°C to +85°C 8-pin DIP MIC2505-1BM Active-High No –40°C to +85°C 8-pin SOIC MIC2505-1BN Active-High No –40°C to +85°C 8-pin DIP MIC2505-2BM Active-Low No –40°C to +85°C 8-pin SOIC MIC2505-2BN Active-Low No –40°C to +85°C 8-pin DIP

Dual Switch

MIC2506BM Active-High Yes –40°C to +85°C 8-pin SOIC MIC2506BN Active-High Yes –40°C to +85°C 8-pin DIP

Pin Configuration

MIC2505/-1/-2

CTL

FLG

2 3

GND

GATE

(CTL A) 1 (FLG A) 2

(GATE A) 4

8-Pin SOIC (M)

8-Pin DIP (N)

MIC2505/-1/-2

LOGIC,

CHARGE

PUMP

3 (GND)

OUT

6, 8 (OUT)

5, 7 (IN)

CTL A FLG A FLG B CTL B

(CTL A) 1

(FLG A) 2 (FLG B) 3

(CTL B) 4

MIC2506

1 2 3 4

MIC2506

LOGIC,

CHARGE

PUMP

LOGIC,

CHARGE

PUMP

6 (GND)

8-Pin SOIC (M)

8-Pin DIP (N)

OUT A

GND

OUT B

8 (OUT A)

7 (IN)

5 (OUT B)

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MIC2505/2506 Micrel

Pin Description

Pin Number Pin Number Pin Name Pin Function

MIC2505 series

1 1 / 4 CTL (A/B) Control (Input): TTL compatible control input. High input typically > 1.8V.

2 2 / 3 FLG (A/B) Fault Flag (Output): Active-low, open-drain output. If CTL is low, indicates

3 6 GND Ground: Return. 4 — GATE Output MOSFET Gate: Open for fastest rise time. Connect capacitor to

5, 7 7 IN Supply Input: Output MOSFET drain. Also supplies IC’s internal circuitry.

6, 8 8 / 5 OUT (A/B) Switch Output: Output MOSFET source. Typically connect to switched side

MIC2506

Low input typically < 1.6V. MIC2505, MIC2505-1 and MIC2506 are active high. MIC2505-2 is active low.

open load. If CTL is high, indicates current limit, thermal shutdown, or UVLO.

MIC2505-1 and -2 do not support open-load detect

ground to slow rise time. (See MIC2505 Turn-On Delay graph)

Connect to supply.

MIC2505 series only:

of load. Output voltage can be pulled above input voltage in off mode.

MIC2505 series only:

Pins 5 and 7 must be externally connected together.

Pins 6 and 8 must be externally connected together.

Absolute Maximum Ratings

Supply Voltage (VIN) ....................................................8.0V

Fault Flag Voltage (V Fault Flag Current (I Output Voltage (V Output Current (I Gate Voltage (V Control Input (V

OUT

GATE

CTL

).............................................7.5V

FLG

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

FLG

) .................................................7.5V

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

) ......................................... VIN + 15V

) ....................................... –0.3V to 15V

Operating Ratings

Supply Voltage (VIN) ................................... +2.7V to +7.5V

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

Thermal Resistance

SOIC (θJA).........................................................160°C/W

DIP (θJA)............................................................105°C/W

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

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

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MIC2505/2506 Micrel

Electrical Characteristics

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

Supply Current MIC2505-1 V

MIC2506 V MIC2505-2 V

Control Input Voltage V

Control Input Current V

Control Input Capacitance 1pF Output MOSFET Resistance MIC2505 series V

MIC2506 V

Output Turn-On Delay MIC2505 series RL = 10Ω, C

MIC2506 RL = 10Ω each output 100 700 2000 µs

Output Turn-On Rise Time MIC2505 series RL = 10Ω, C

MIC2506 RL = 10Ω each output 200 2000 6000 µs

Output Turnoff Delay MIC2505 series RL = 10Ω, C

MIC2506 RL = 10Ω each output 0.8 20 µs

Output Turnoff Fall Time MIC2505 series RL = 10Ω, C

MIC2506 RL = 10Ω each output 0.7 20 µs Output Leakage Current 10 µA Current Limit Threshold MIC2505 series 2 4A

MIC2506 1 23A Open Load Threshold, Note 1 V Overtemperature Shutdown T

Threshold TJ decreasing 125 °C Error Flag Output Resistance V

Error Flag Off Current V UVLO Threshold V

= logic 0, OUT = open 0.75 5 µA

CTL

= logic 1, OUT = open 110 160 µA

CTL

= logic 0, OUT = open 110 160 µA

CTL

= logic 1, OUT = open 0.75 5 µA

CTL

= logic 0 → logic 1 transition 2.1 2.4 V

CTL

= logic 1 → logic 0 transition 0.8 1.9 V

CTL

= logic 0 0.01 1 µA

CTL

= logic 1 0.01 1 µA

CTL

= 5V, TA = 25°C3050 mΩ

= 5V, –40°C < TA < +85°C 60 mΩ

= 3.3V, TA = 25°C3560 mΩ

VIN = 3.3V, –40°C < TA < +85°C 75 mΩ

= 5V, TA = 25°C75125 mΩ

= 5V, –40°C < TA < +85°C 150 mΩ

= 3.3V, TA = 25°C80135 mΩ

VIN = 3.3V, –40°C < TA < +85°C 165 mΩ

= 0 200 850 2000 µs

GATE

= 0 500 3000 7500 µs

GATE

= 0 0.7 20 µs

GATE

= 0 1.5 20 µs

GATE

= logic low, Note 2 0.5 1 1.5 V

CTL

increasing 135 °C

= 5V, IL = 10mA 10 25 Ω

VIN = 3.3V, IL = 10mA 15 40 Ω

= 5V 0.01 1 µA

FLAG

= increasing 2.2 2.5 2.7 V

VIN = decreasing 2.0 2.3 2.5 V

General Note: Devices are ESD protected, however, handling precautions recommended. General Note: All limits guaranteed by testing or statistical analysis. Note 1: MIC2505-1 and -2 versions have no open load detect feature. Note 2: Open-load threshold is the output voltage (V

resistor to VIN.

) where FLG becomes active (low) when CTL is low. OUT is pulled high by a 100k external

OUT

MIC2505/2506 4 April 1998

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MIC2505/2506 Micrel

100

2345678

OUTPUT RESISTANCE (mΩ)

SUPPLY VOLTAGE (V)

100

-40 -20 0 20 40 60 80 100

ON RESISTANCE (mΩ)

TEMPERATURE (°C)

0.5

1.0

1.5

2.0

2345678

SUPPLY CURRENT (µA)

SUPPLY VOLTAGE (V)

Test Circuits

GND

+5V

10Ω

1µF

10Ω

+5V

10kΩ

FLG

MIC2505/-1/-2

CTL OUT FLG GND OUT GATE IN

10kΩ

A ON

A OFF

B ON

B OFF

V V

FLG A

FLG B

10Ω

1µF

MIC2506BM

CTL A OUT A FLG A FLG B CTL B OUT B

Typical Characteristics Note 2

MIC2505 Turn-On, Turnoff

Characteristics

CONTROL (V)

-5

4 2 0

OUTPUT (V)

-2

-2 0246

TIME (ms)

RL = 5Ω

= 1A)

-2 024

TIME (µs)

MIC2506 Turn-On, Turnoff

Characteristics

CONTROL (V)

-5

4 2 0

OUTPUT (V)

-2

-2 0246

TIME (ms)

RL = 5Ω

= 1A)

-1 012

TIME (µs)

Output On Resistance

vs. Supply Voltage

MIC2506

MIC2505

UVLO Threshold Voltage

3.0

2.5

2.0

THRESHOLD VOLTAGE (V)

1.5

vs. Temperature

VIN RISING

VIN FALLING

-40 -20 0 20 40 60 80 100

TEMPERATURE (°C)

Output On Resistance

vs. Temperature

MIC2506

MIC2505

Error Flag Voltage

vs. Error Flag Current

400

FLG = ACTIVE

300

VDD = 3.3V

200

100

ERROR FLAG VOLTAGE (mV)

0.1 1 10 100

ERROR FLAG CURRENT (mA)

VDD = 5V

On-State Supply Current

200 180 160 140 120 100

April 1998 5 MIC2505/2506

80 60 40

SUPPLY CURRENT (µA)

2345678

vs. Supply Voltage

SUPPLY VOLTAGE (V)

Off-State Supply Current

vs. Supply Voltage

Control Threshold

vs. Supply Voltage

2.5

2.0

1.5

THRESHOLD VOLTAGE (V)

1.0 2345

RISING

CTL

FALLING

CTL

SUPPLY VOLTAGE (V)

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MIC2505/2506 Micrel

On-State Supply Current

200 180 160 140 120 100

SUPPLY CURRENT (µA)

vs. Temperature

80 60 40 20

-40 -20 0 20 40 60 80 100

TEMPERATURE (°C)

Off-State Supply Current

2.0

1.5

1.0

0.5

SUPPLY CURRENT (µA)

vs. Temperature

-40 -20 0 20 40 60 80 100

TEMPERATURE (°C)

MIC2505 Turn-On Delay

with External Gate Capacitance

1000

800

600

400

200

TURN-ON DELAY (ms)

0 50 100 150 200 250

CAPACITANCE (nF)

Control Threshold

2.5

2.0

1.5

THRESHOLD VOLTAGE (V)

vs. Temperature

RISING

CTL

FALLING

CTL

-40 -20 0 20 40 60 80 100

TEMPERATURE (°C)

MIC2505/2506 6 April 1998

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MIC2505/2506 Micrel

Block Diagrams

CTL

CTL A

OSC.

CHARGE

PUMP

MIC2505/2505-1/2505-2

CHARGE

PUMP

THERMAL

SHUTDOWN

UVLO

REFERENCE

GATE

CONTROL

Not Included in

MIC2505-1, -2

OPEN LOAD

DETECT

MIC2505-Series Block Diagram

OPEN LOAD

DETECT

GATE

CONTROL

1.2V

GATEGND

CURRENT

LIMIT

CURRENT

OUT FLG

FLG A

OUT A

LIMIT

CTL B

MIC2506

OSC.

CHARGE

PUMP

THERMAL

SHUTDOWN

UVLO

OPEN LOAD

GND

MIC2506 Block Diagram

REFERENCE

GATE

CONTROL

DETECT

1.2V

CURRENT

LIMIT

OUT B FLG B

April 1998 7 MIC2505/2506

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MIC2505/2506 Micrel

Functional Description

The MIC2505-series and MIC2506 are high-side N-Channel switches. The MIC2505, MIC2505-1, and MIC2506 have active-high enable inputs. The MIC2505-2 has an active-low input. Fault conditions inhibit output transistor turn-on or turnoff when enabled.

Control Input

CTL (control input) activates the oscillator, thermal shutdown, UVLO, 1.2V reference, and gate control circuits. If there are no fault conditions, the output MOSFET turns on when enabled.

Reference

A 1.2V bandgap reference supplies a regulated voltage to the thermal shutdown and undervoltage lockout circuits. The reference is only active when CTL is enabled.

Oscillator/Charge Pump

The oscillator produces an 80kHz square wave output which drives the charge pump. The oscillator is enabled when CTL is active.

The charge pump is a voltage quintupler (5×). The charge pump capacitors are self contained.

Gate Control

The gate control circuit charges the output MOSFET gate from the charge pump output or discharges the MOSFET gate to ground as determined by CTL, thermal shutdown, or UVLO (undervoltage lockout).

An optional, external capacitor may be connected to the MIC2505 GATE to lengthen the rise time. This slows the turn on of the MOSFET output switch. (See “MIC2505 Turn-On Delay” graph.) Since this pin connects directly to the MOSFET gate, use ESD precautions when contacting components connected to this pin. Leakage resistance may increase turnon times.

Input and Output

IN (input) is the supply connection to the logic circuitry and the drain of the output MOSFET. OUT (output) is the source of the output MOSFET. In a typical circuit, current flows through the switch from IN to OUT toward the load.

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 (V off and VIN > UVLO minimum. In this situation, the MIC2505/6 avoids undesirable drain to body diode reverse current flow by grounding the body when the switch is off. (The conventional method for optimum turn-on threshold has the source connected to the body. This would allow a large current to flow when V

source

> V

drain

MIC2505 Series Only

> VIN) when the output switch is

OUT

+ 0.6V.)

Duplicate IN and OUT leads are not internally connected. Connect both IN pins to the supply. Connect both OUT leads to the load.

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 control input is enabled (output MOSFET is on). Both MIC2506 outputs are shut off during overtemperature, and both flags will go low.

Undervoltage Lockout

UVLO (undervoltage lockout) prevents the output MOSFET from turning on until VIN (input voltage) exceeds 2.5V typical. After the switch turns on, if VIN drops below 2.3V typical, UVLO shuts off the output MOSFET and turns the fault flag on (active low) until VIN drops below 1.5V.

Undervoltage detection functions only when the control input is enabled (output MOSFET is on).

Overcurrent Limit

The overcurrent limit is preset internally. The preset level prevents damage to the output MOSFET but allows a minimum current of 2A through the output MOSFET of the MIC2505-series and 1A for each output MOSFET of the MIC2506. Output current is monitored by sensing the voltage drop across the output MOSFET drain metal resistance.

Overcurrent detection functions only when the control input is enabled (output MOSFET is on) and VIN is above the UVLO threshold.

Open-Load Detection

Open-load detection is available only on the MIC2505 and MIC2506. The open-load detection feature is not included in the MIC2505-1 or -2 versions.

Open-load detection indicates the absence of an output load by activating the fault flag. Open-load detection is optional and is enabled by connecting a high-value pull-up resistor between IN and OUT. If there is no load, the circuit detects a high OUT (output) voltage (typically ≥1V) and signals the fault flag. Under normal conditions, the low resistance of a typical load pulls OUT low. Open-load detection functions only when the control input is low (output MOSFET is off).

Fault Flag

FLG is an N-channel, open-drain MOSFET output. The faultflag is active (low) for one or more of the following conditions: open load (except MIC2505-1 and -2 versions), undervoltage, current limit, or thermal shutdown. The flag output MOSFET is capable of sinking a 10mA load to typically 100mV above ground.

MIC2505/2506 8 April 1998

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MIC2505/2506 Micrel

Applications Information

Supply Filtering

A 0.1µF to 1µF bypass capacitor from IN to GND, located at 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 destroy the internal control circuitry.

Input transients must not exceed the absolute maximum supply voltage (V

OFF

Figure 1. Supply Bypassing

The bypass capacitor may be omitted only if board design precautions are followed, such as using extremely short supply leads or power and ground planes.

Control Input

CTL 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. Add a diode clamp if negative spikes may occur. See Figure 2.

Open-Load Detection

Refer to “Typical Applications” (first page). Open-load detection is available only on the MIC2505 and MIC2506. For USB power distribution applications, the open-load detection feature is not included in the MIC2505-1 or -2 versions.

The optional open-load detection resistor supplies a small pull-up current to the load when the output switch is off. (A 100k resistor will draw 50µA from a 5V supply.) Normally, the load dominates, pulling OUT low. If the load is absent, the optional resistor pulls OUT high, activating the fault flag if CTL is off.

When a load is switched off with CTL, capacitance on the output may cause the open-load function to pull the flag low until the capacitor is discharged below approximately 2.4V.

Omit the pull-up resistor when open load detection is not required and for minimum off-state supply current.

Power Bus Switch

The MIC2505/6 family features a MOSFET reverse current flow prevention circuit. This prevents current from flowing backwards (from OUT to IN) when CTL is disabled as long as VIN is above UVLO minimum. In Figure 2, when U1 is on and

= 7.5V) even for a short duration.

IN max

2.7V to 7.5V

MIC2505BM

CTL OUT

FLG

GND OUT

GATE IN

0.1µF to 1µF

U2 is off, this feature prevents current flow from the load (5V) backward through U2 to the 3.3V supply. (If a discrete MOSFET and driver were used, the MOSFET’s internal body diode would short the 5V load to the 3.3V supply.)

FLG will be active (low) on any switch that is off whenever the load voltage is greater than the open load threshold (approximately 1V) except for MIC2505-1 and MIC2505-2.

Logic-High = 5V Output

Logic-Low = 3.3V Output

1N4148

(optional)

+5V

MIC2505BM

CTL OUT

FLG

GND OUT

GATE IN

0.1µF

Load

MIC2505BM

CTL OUT

FLG

GND OUT

GATE IN

+3.3V

0.1µF

Figure 2. 5V/3.3V Switch Concept

This circuit’s function would otherwise require a dual driver, two MOSFETs, plus two diodes (or a dual driver plus four MOSFETs).

Hot Plug-In Applications (Soft-Start)

The MIC2505/6 family can be used to protect the socket-side and card-side of a supply circuit from transients caused when a capacitive load is connected to an active supply.

The switch presents a high impedance when off, and slowly becomes a low impedance as it turns on. This reduces the inrush current and related voltage drop that result from charging a capacitive load.

Power Control

3.3V

GND

MIC2505BM

CTL OUT

FLG

GND OUT

GATE IN

CardSocket

0.1µF

Circuitry

Capacitive

Load

Figure 3. Hot Plug-In Concept

A gate capacitor may be added to the MIC2505 to slow the turn on time even more, reducing the inrush current. See “MIC2505 Turn-On Delay” graph. The UVLO feature insures that each time the card is removed and VIN = 0 that the gate of the output switch is discharged to zero volts. A controlled turn-on is executed each time a board is plugged in, even with multiple insertions.

April 1998 9 MIC2505/2506

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MIC2505/2506 Micrel

Applications Information

USB Application

Figure 4 depicts a low cost and robust implementation of a four-port, self-powered USB hub circuit employing ganged overcurrent protection.

Ferrite

(+)

4.45V to 5.25V

3.5A max. (–)

V D+ D– GND

BUS

33µF

MIC5203-3.3 MIC5207-3.3

LDO Regulator

IN OUT

4.7 µF

GND

V+

1.0

OVERCURRENT

µF

D+ D–

100k

GND

ON/OFF

MIC2505-2/-13.3V USB Controller

EN OUT FLG IN GND OUT GATE IN

33µF

0.1µF 33µF

Bead

0.01µF

BUS

D+ D–

GND

BUS

D+ D–

GND

Downstream

USB

Port 1

500mA max.

Downstream

USB

Port 2

500mA max.

Bold lines indicate

0.1" wide, 1-oz. copper high-current traces.

Figure 4. Ganged-Switch Self-Powered Hub

33µF

Data

0.01µF

BUS

D+ D–

GND

BUS

D+ D–

GND

Downstream

USB

Port 3

500mA max.

Downstream

USB

Port 4

500mA max.

MIC2505/2506 10 April 1998

Page 11

MIC2505/2506 Micrel

Package Information

0.026 (0.65) MAX)

PIN 1

0.157 (3.99)

0.150 (3.81)

0.050 (1.27)

0.064 (1.63)

0.045 (1.14)

TYP

0.197 (5.0)

0.189 (4.8)

0.380 (9.65)

0.370 (9.40)

DIMENSIONS:

INCHES (MM)

0.020 (0.51)

0.013 (0.33)

0.0098 (0.249)

0.0040 (0.102)

0°–8°

SEATING

PLANE

8-Pin SOIC (M)

PIN 1

0.135 (3.43)

0.125 (3.18)

45°

0.050 (1.27)

0.016 (0.40)

0.244 (6.20)

0.228 (5.79)

DIMENSIONS:

INCH (MM)

0.010 (0.25)

0.007 (0.18)

0.255 (6.48)

0.245 (6.22)

0.300 (7.62)

0.018 (0.57)

0.100 (2.54)

0.130 (3.30)

0.0375 (0.952)

8-Pin DIP (N)

0.013 (0.330)

0.010 (0.254)

0.380 (9.65)

0.320 (8.13)

April 1998 11 MIC2505/2506

Page 12

MIC2505/2506 Micrel

MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 USA

TEL + 1 (408) 944-0800 FAX + 1 (408) 944-0970 WEB 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.

MIC2505/2506 12 April 1998