MIC2564A-0YSM Micrel Inc, MIC2564A-0YSM Datasheet - Page 10
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MIC2564A-0YSM
Manufacturer Part Number
MIC2564A-0YSM
Description
IC PCMCIA/CARDBUS DUAL 24-SSOP
Manufacturer
Micrel Inc
Type
PCMCIA/Cardbus Switchr
Datasheet
1.MIC2564A-1YTS.pdf
(14 pages)
Specifications of MIC2564A-0YSM
Number Of Outputs
4
Rds (on)
5 Ohm
Internal Switch(s)
Yes
Current Limit
260mA
Voltage - Input
3.3V, 5V, 12V
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
24-SSOP (0.200", 5.30mm Width)
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
MIC2564A
Applications Information
PC Card power control for two sockets is easily accomplished
using the MIC2564A PC Card/CardBus power controller.
Control commands from a three-wire (plus Reset) serial bus
determine V
or operate mode.
V
Card current are supported. The V
GND (0V) and high-impedance states. The V
support V
high-impedance. When the V
condition is selected, the device switches into sleep mode
and draws only leakage current.
Full protection during hot switching is provided which pre-
vents feedback from the V
supply into the 3.3V supply) by locking out the low-voltage
switch until the initial switch’s gate voltage drops below 0.7V.
MIC2564A internal logic and MOSFET drive circuitry is
powered from the V
voltage multipliers. Switching speeds are carefully controlled
to prevent damage to sensitive loads and meet all PC Card
specification timing requirements, including those for the
CardBus option.
Supply Bypassing
The MIC2564A is a switch and has no stability problems;
however, supply bypass capacitors are recommended to
reduce inductive transients and improve output ripple. As all
internal device logic and comparison functions are powered
from the V
most important. Micrel recommends placing 1 m F surface-
mount ceramic (low ESR) capacitors from V
V
capacitors, one from each V
V
capacitors for noise reduction and to reduce the chance of
ESD (electrostatic discharge) damage.
Power Status Feedback (Flags)
Two flag outputs monitor the V
both slot A and B, falling low when the voltage is not proper.
Use of these open-drain flag outputs is optional; if they are
used, a pull-up resistor to either the 3.3V or 5V supply is
required. Unused flag outputs may be left open.
PC Card Slot Implementation
The MIC2564A is designed for full compatibility with the
PCMCIA (Personal Computer Memory Card International
Association) PC Card Specification including the CardBus
and Zoom Video (ZV) options.
When a PC card is initially inserted, it should receive V
(3.3V ± 0.3V or 5.0V ± 5%). The initial voltage is determined
by a combination of mechanical socket keys and voltage
sense pins. The card sends a handshaking data stream to the
logic controller, which then determines if this card requires
V
M0250-031104
CC
CC5
CC
PP
OUT and V
and if the card is designed for dual V
outputs of 3.3V and 5V at the maximum allowable PC
IN pins to ground and two 0.1 m F surface-mount ceramic
PP
CC3
CC
(12V), V
input, the power supply quality on this line is the
and V
PP
OUT pins may use 0.01 m F to 0.1 m F
CC
PP
CC3
voltages (3.3V or 5V), GND (0V), or
output voltages and select standby
CC
input and internal charge-pump
output (for example, from the 5V
PP
CC
CC
IN pin, to ground. Also, the
and V
= Hi-Z (high-impedance)
CC
PP
outputs also support
output voltages on
CC
. If the card is
CC3
PP
outputs
IN and
CC
10
compatible with, and requires, a different V
controller commands the power controller to make this change
by disabling V
enabling the other V
If no card is inserted, or the system is in sleep mode, the logic
controller commands the MIC2564A to shut down V
also places the switch into a shutdown (sleep) mode, where
current consumption drops to nearly zero, with only tiny
CMOS leakage currents flowing.
Internal device control logic, MOSFET drive and bias voltage
is powered from V
by an internal charge pump multiplier. Input logic threshold
voltages are compatible with common PC Card logic control-
lers using either 3.3V or 5V supplies.
PC Card Voltage Regulation
The MIC2564A has been designed to meet or exceed PC
Card voltage regulation specifications. The on-resistance of
the FET switches will meet regulation requirements at 600mA
and 1A respectively for V
Flash Memory Implementation
When programming flash memory (standard +12V flash
memories), the PC Card slot logic controller enables V
the MIC2564A, which connects V
V
allows using a small bypass capacitor on the V
with the main filtering performed by a large filter capacitor on
V
sufficient.) Using a small-value capacitor such as 0.1 m F on
the output causes little or no timing delays.
The V
200 m s. After programming is completed, the logic controller
signals to the MIC2564A, which then reduces V
V
trolled rise times reduce switching transients and lower
current spikes through the switch.
Output Current and Protection
The MIC2564A meets or exceeds all PCMCIA specifications.
MIC2564A output switches are capable of passing the maxi-
mum current needed by any PC Card. For system and card
protection, output currents are internally limited. For full
system protection, long term (longer than a few milliseconds)
output short circuits invoke overtemperature shutdown, pro-
tecting the MIC2564A, the system power supplies, the card
socket pins, board traces, and the PC Card. Individual
internal status registers for each slot indicate when power
problems exist.
Control Bus Interface Overview
The MIC2564A power controller communicates with a logic
controller (host adapter) via a 3-wire serial interface. A fourth
control line attaches to the system reset line (RST#) and
places all MIC2564A switches in the high-impedance (off)
state. The reset function is active low.
PP
PP
CC
OUT. The low on-resistance of the MIC2564A switch
IN. (Usually the main power supply filter capacitor is
level. Break-before-make switching action and con-
PP
OUT transition from V
CC
CC3
, waiting at least 100ms, and then re-
CC
IN. The high voltage bias is generated
voltage.
CC
= 5V ± 3% and 3.3V ± 3%.
CC
PP
to 12.0V typically takes
IN (nominally +12V) to
CC
level, the logic
PP
PP
March 2004
OUT to the
OUT pins,
CC
Micrel
PP
. This
on