ETC B2526-1M

Bay Linear
Inspire the Linear Power
B2526
Dual USB High Side Power Switch
Description
Features
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The Bay Linear B2526 is a dual high-side power switch
recommended for self-powered and bus-powdered universal
serial for bus (USB) application conforming to USB
requirements. USB voltage drop requirements, fault current
limited to 750mA, flag output to indicate fault connections to
the local USB controller are features that meet USB
requirements.
Additional features such as thermal shutdown to prevent
catastrophic switch failure from excessively high current
loads, under voltage lockout (UVLO) to ensure that the device
remains off unless there is a valid input voltage present, and
3.3V or 5V logic compatible enable inputs. Two versions of
the enable pin, Active High or Active Low are available in 8pin Dip and 8-pin SOIC packages.
Package Information
3.0V to 5.5V Input
110µ
µA Typical on-State Supply Current
1µ
µA Typical off-State Supply Current
500mA Minimum Continuous Load Current
1.25A Maximum Current Limit
2.4V Typical Under Voltage Lockout (UVLO)
Open-Drain Fault Flag Pin
Thermal Shutdown
Available with Active-High or Active-Low Enable
Applications
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USB Host and self-Powered Hubs
USB Power Management
Battery-Charger Circuits
Hot Plug-In Power Supplies
Bus-Powered Hubs
Ordering Information
Package
Active High
B2526-1M
B2526-1P
SO-8
8 DIP
EN (A)
FLG (A)
SO-8
EN (A)
1
8
FLAG (A)
2
FLAG (B)
3
BAY 7
B2526
6
EN (B)
4
5
1
2
Logic
Charge
Pump
3
4
Logic
Charge
Pump
VOUT (A)
VIN
GND
FLB (B)
EN (B)
Active Low
B2526-2M
B2526-2P
8
Out (A)
7
IN
5
Out (B)
VOUT (B)
Top View
Bay Linear, Inc
Enable
2418Armstrong St., Livermore CA USA 94550
6
GND
Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
B2526
ABSOLUTE MAXIMUM RATINGS
OPERATING RATING
Supply Voltage…………………………………...6V
Fault Flag Voltage………………………………..6V
Fault Flag Current……………………………..50mA
Output Voltage……………………………………6V
Output Current……………………Internally Limited
Enable Input……………………………-0.3V to 12V
Storage Temperature………………-65°C to +150°C
Lead Temperature (Soldering 5 sec.)………….260°C
Supply Voltage ..................................................+3V to +5.5V
Ambient Operating Temperature.................... -40°C to +85°C
Thermal Resistance
SOIC .................................................................. 120°C/W
DIP..................................................................... 130°C/W
ELECTRICAL CHARACTERISTICS at VIN = 5V, Ta=25°C, unless otherwise specified. (Note 1)
Units
Parameters
Conditions
Typ
Supply Current
(Note1) Switch Off, OUT = Open
(Note1) Switch On, OUT = Open
Low to High Transition
High to Low Transition, (Note1)
VEN = 0V to 5.5V
0.75
110
2.1
1.9
± 0.01
1
100
140
0.5
1
1
1
Min
Enable Input Threshold
Enable Input Current
Enable Input Capacitance
Switch Resistance
Output Turn-On Delay
Output Turn-On Rise Time
Output Turn-Off Delay
Output Turn-Off Fall Time
Output Leakage Current
Continuous Load Current
Short Circuit Current Limit
Current Limit Threshold
Over temperature Shutdown
Threshold
Error Flag Output Resistance
Error Flag Off Current
UVLO Threshold
VIN = 5V
IOUT = 500mA, Each Switch
VIN = 3.3V IOUT = 500mA, Each Switch
RL = 10Ω
RL = 10Ω
RL = 10Ω
RL = 10Ω
Each output (output disabled)
Each output
Each output (enable into load), VOUT = 4.0V
Ramped Load applied to enable output, VOUT ≤ 4.0V
TJ Increasing
TJ Decreasing
VIN = 5.0V, IL = 10mA
VIN = 3.3V, IL = 10mA
VFLAG = 5V
VIN = Increasing
VIN = Decreasing
0.8
-1
Max
5
160
µA
2.4
V
1
µA
pF
140
180
mΩ
20
20
10
0.5
0.5
0.75
1.6
135
125
10
15
0.01
2.5
2.3
1.25
2.2
ms
ms
µs
µs
µA
A
A
A
°C
Ω
1
µA
V
General Note: Devices are ESD protected, however, handling precautions recommended.
Note 1: Off is ≤ 0.8V and is ≥ 2.4V for the B2526-1. Off is ≥ 2.4V and on is ≤ 0.8V for the B2526-2. The Enable input has approximately 200mV of hysteresis.
TEST CIRCUIT
(Only 1 Output Shown)
5V
0.1µ
µF
Ferrite
Bead
10K
B2526
EN (A)
FLG (A)
FLG (B)
EN (B)
Out (A)
IN
IOUT
RL
CL
+
GND
ILOAD
(for Current
Limit
Response)
Out (B)
Functional Characteristics Test Circuit
Bay Linear, Inc
2418Armstrong St., Livermore CA USA 94550
Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
B2526
PIN DESCRIPTION
Pin No.
Pin Name
1&4
EN (A)/(B)
2&3
FLAG (A)/(B)
6
GND
7
VIN
8&5
VOUT (A)/(B)
Pin Function
Enable (Input): Logic-compatible enables input. High input > 2.1V typical.
Low input < 1.9V typical (B2526-1 active high, B2526 -2 active low).
Fault Flag (Output): Active-low, open-drain output. Indicates over current,
UVLO and thermal shutdown.
Ground: Supply return.
Supply Input: Output MOSFET drain. Also supplies IC’s internal circuitry. Connect to positive
supply.
Switch Output: Output MOSFET source. Typically connect to switched side of load.
DETAILED DESCRIPITION
Power Switch
The power switch is an N-Channel MOSFET with a maximum on-state resistance of 140mΩ (VIN = 5V). the power switch supplies a
minimum of 500mA per switch.
Enable
The Logic enable disables the power switch and the bias for the charge pump, driver and other circuitry to reduce the supply current to
less than 5µA when a logic high is present on the EN pin for B2526-2 or a logic low is present on EN for B2526-1. The enable input
is compatible with both TTL and CMOS logic levels.
Driver
The driver controls the gate voltage of the power switch. To Limit large current surges the driver incorporates circuitry that controls
the rise and fall times of the output voltage.
Charge Pump
An internal charge pump supplies power to the driver circuit and provides the necessary voltages to pull the gate of the MOSFET
above the source.
Fault Flag FLG (A)/(B)
FLG is a N-Channel, open drain MOSFET output. The fault flag is active (low) for one or more of the following conditions: undervoltage (while 2V < VIN < 2.7V), current limit or thermal shutdown. The flag output MOSFET is capable of sinking a 10mA load to
typically 100mV above ground. Multiple FLG pins may be “wired NORed” to a common pull-up resistor.
Thermal Shutdown
An internal thermal sense circuit shuts off the power switch when the junction temperature rises to approximately 150°C. Hysteresis is
built into the thermal sense circuit.
Current Sense
A sense FET monitors the current supplied to the load. When an overload or short circuit is encountered, the current sense circuitry
sends a control signal to the driver. The driver in turn reduces the gate voltage and sends the power FET into its saturation region,
which switches the output into a constant current mode. The 2526 current-limit profile exhibits a small foldback effect of
approximately 500mA. Once this current-limit threshold is exceeded the device enters constant current mode. The constant current is
specified as the short circuit current limit in the “Electrical Characteristics" table. It is important to note that the 2526 will deliver load
current up to the current-limit Threshold which is typically 1.6A (2.2Amax)."
Under-Voltage Lockout (UVLO)
UVLO prevents the output MOSFET form turning on until VIN exceeds 2.5V. In the under-voltage state, the FLG will be low. After
the switch turns on, if the voltage drops below approximately 2.3V, UVLO shuts off the output MOSFET and signals fault flag.
Under-voltage detection functions only when at least one switch is enabled.
Bay Linear, Inc
2418Armstrong St., Livermore CA USA 94550
Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
B2526
Bay Linear, Inc
2418Armstrong St., Livermore CA USA 94550
Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
B2526
B4300
B2526
Two-Port Self Powered Hub (Using B2526 & B4300)
Bay Linear, Inc
2418Armstrong St., Livermore CA USA 94550
Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
B2526
BLOCK DIAGRAM
TYPICAL APPLICATION
VCC 5V
10K
100K
10K
100K
3.3V USB Controller
B2526-2
VIN
µF
0.1µ
ON/OFF
EN (A)
VBUS
D+
FLG (A)
IN
Over-Current
FLG (B)
GND
D-
+
Out (A)
Over-Current
ON/OFF
Ferrite
Beads
47µF
47µ
USB
Port
1
GND
µF
0.1µ
EN (B)
VBUS
Out (B)
D+
D-
+
USB
Port
2
GND
47µF
47µ
Data
(Two Pair to USB Controller)
2 Port USB Self-Powered Hub
Bay Linear, Inc
2418Armstrong St., Livermore CA USA 94550
Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
Advance Information- These data sheets contain descriptions of products that are in development. The specifications are based on the engineering calculations, computer simulations and/
or initial prototype evaluation.
Preliminary Information- These data sheets contain minimum and maximum specifications that are based on the initial device characterizations. These limits are subject to change upon the
completion of the full characterization over the specified temperature and supply voltage ranges.
The application circuit examples are only to explain the representative applications of the devices and are not intended to guarantee any circuit design or permit any
industrial property right to other rights to execute. Bay Linear takes no responsibility for any problems related to any industrial property right resulting from the use of
the contents shown in the data book. Typical parameters can and do vary in different applications. Customer’s technical experts must validate all operating parameters
including “ Typical” for each customer application.
LIFE SUPPORT AND NUCLEAR POLICY
Bay Linear products are not authorized for and should not be used within life support systems which are intended for surgical implants
into the body to support or sustain life, in aircraft, space equipment, submarine, or nuclear facility applications without the specific
written consent of Bay Linear President.
Bay Linear, Inc
2418Armstrong St., Livermore CA USA 94550
Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com