MIC2076-1YM Micrel Inc, MIC2076-1YM Datasheet - Page 13

• Manufacturer Part Number: MIC2076-1YM
• Description: IC,Power Supply Switching Circuit,SOP,8PIN,PLASTIC
• Manufacturer: Micrel Inc
• Type: High Side Switchr

Specifications of MIC2076-1YM

• Number Of Outputs: 2
• Rds (on): 140 mOhm
• Internal Switch(s): Yes
• Current Limit: 900mA
• Voltage - Input: 2.7 ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Short Circuit Current Limit: 900mA
• Input Voltage Range: 2.7 to 5.5V
• Number Of Switches: Dual
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 8
• Package Type: SOIC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 576-2145; MIC2076-1YM

Application Information
Supply Filtering
A 0.1µF to 1µF bypass capacitor positioned close to V
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 MIC2026/76 are ideal inrush current-limiters for hot
plug applications. Due to their integrated charge pumps,
the MIC2026/76 present a high impedance when off and
slowly become a low impedance as their integrated
charge pumps turn on. This “soft-start” feature effectively
isolates power supplies from highly capacitive loads by
reducing inrush current. Figure 3 shows how the
MIC2076 may be used in a card hot-plug application.
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 should be selected to
match the length of the transient, less t
MIC2026/76.
Micrel, Inc.
June 2010
to "Hot"
Receptacle
GND
V
BUS
Cable
D(min)
Figure 3. Hot-Plug Application
4.7
µF
of the
IN
1
2
3
4
USB Peripheral
ENA
FLGA
FLGB
ENB
SPN010012
13
OUTA
OUTB
Universal Serial Bus (USB) Power Distribution
The MIC2026/76 are 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 shows a typical USB Host application
that may be suited for mobile PC applications employing
USB. The requirement 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. Please refer to Application Note
17 for more details on designing compliant USB hub and
host systems.
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 V
soft-start is necessary. Although the hub can consume
up to 500mA from the upstream bus, the hub must
consume
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.
GND
IN
8
5
7
6
only
C
BULK
C
100mA
BULK
Controller
Function
Function
USB
USB
USB
max
at start-up,
M9999-060410-B
MIC2026/2076
until
BUS
it
,