DC1263A - Demo Manual

DEMO CIRCUIT 1263
QUICK STARTLTC4558
GUIDE
LTC4558
Dual SIM Smart Card
Power Supply and InterDESCRIPTION
Demonstration circuit 1263 is a Dual SIM Smart
Card Power Supply and Interface featuring the
LTC4558.
The LTC®4558 provides the power conversion and
signal level translation needed for advanced cellular telephones to interface with 1.8V or 3V subscriber identity modules (SIMs). The device meets
all requirements for 1.8V and 3V SIMs and contains LDO regulators to power 1.8V or 3V SIM
cards from a 2.7V to 5.5V input. The output voltages can be set using the two voltage selection
pins and up to 50mA of load current can be supplied. A channel select pin determines which
channel is open for communication. Separate enable pins for each channel allow both cards to be
PERFORMANCE SUMMARY
PARAMETER
VBATT Input Supply Range
DVCC Input Supply Range
VCCA,B Output Voltage Range
CLOCKA,B FREQUENCY
CLOCKA,B RISE/FALL TIME
CLOCKA,B LOW LEVEL OUTPUT
CLOCKA,B HIGH LEVEL OUTPUT
RSTA,B LOW LEVEL OUTPUT
RSTA,B HIGH LEVEL OUTPUT
I/OA,B LOW LEVEL OUTPUT
I/OA,B HIGH LEVEL OUTPUT
DATA LOW LEVEL OUTPUT
DATA HIGH LEVEL OUTPUT
LOW LEVEL INPUT (VIL)
HIGH LEVEL INPUT (VHL)
powered at once and allow for faster transition
from one channel to the other.
Internal level translators allow controllers operating
with supplies as low as 1.4V to interface with 1.8V
or 3V Smart Cards. Battery life is maximized by a
low operating current of 65 A and a shutdown current of less than 1 A. Board area is minimized by
the low profile 3mm × 3mm × 0.75mm leadless
QFN package.
Design files for this circuit board are available.
Call the LTC factory.
L, LTC, LT, are registered trademarks of Linear Technology Corporation. Other
product names may be trademarks of the companies that manufacture the products.
Specifications are at TA = 25°C
CONDITIONS
3V Mode, 0mA<ICCA,B<50mA
18V Mode, 0mA<ICCA,B<50mA
Loaded with 50pF (10% to 90%)
Sink Current = -200uA
Source Current = 200uA
Sink Current = -200uA
Source Current = 200uA
Sink Current = -1mA (DATA = 0V)
Source Current = 20Ua (VDATA = VDVCC)
Sink Current = -500uA (VI/OA,B = 0V)
Source Current = 20Ua (VI/OA,B = VCCA,B)
MIN
2.7
1.4
2.85
1.71
10
VCCA,B -0.2
VCCA,B -0.2
0.85*VCCA,B
0.8*DVCC
0.85*DVCC
TYP
3.00
1.8
MAX
5.5
5.5
3.15
1.89
UNITS
V
V
V
V
MHz
16
ns
0.2
V
V
0.2
V
V
0.3
V
V
0.3
V
V
0.15*DVCC
V
V
QUICK START PROCEDURE
1
LTC4558
Demonstration circuit 1263 is easy to set up to
evaluate the performance of the LTC4558. Refer to
Figure 1 for proper measurement equipment setup
and follow the procedure below:
NOTE. When measuring the input or output voltage ripple, care
must be taken to avoid a long ground lead on the oscilloscope
probe. Measure the input or output voltage ripple by touching the
probe tip directly across the VBATT, VCCA, or VCCB and GND
terminals. See Figure 2 for proper scope probe technique.
1. Place jumpers in the following positions:
JP1 ENABLEA: LO
JP2 VSELA: HI
JP3 CSEL: LO
JP4 CLKRUNA: LO
JP5 CLKRUNB: LO
JP6 VSELB: HI
JP7 ENABLEB: LO
2. With power off, connect the input power supply
(PS1), capable of supplying at least 200mA, to
VBATT and GND terminals.
3. With power off, connect the input power supply
(PS2) to DVCC and GND terminals. If desired, a
single supply may be used for VBATT and
DVCC providing the supply is set within the
VBATT operating range.
4. Turn on the PS1 power supply and set the voltage between 2.7V and 5.5V.
NOTE. Make sure that the input voltage does not exceed 6V.
5. If using two power supplies, turn on the PS2
power supply and set the voltage between 1.4V
and 5.5V.
NOTE. Make sure that the input voltage does not exceed 6V.
2
6. If SIM/Smart Cards are to be used for evaluation, insert cards into one or both card sockets.
7. To enable one or both of the card sockets, move
the ENABLEA and/or ENABLEB jumpers to the
HI position.
8. The VCCA or VCCB voltages may be selected
by changing the positions of the VSELA or
VSELB jumpers, respectively.
9. Move the CSEL jumper to the LO position to
communicate with Card Socket A, or the HI position to communicate with Card Socket B.
10. The CLOCK, DATA and RESET channels may
be tested by applying signals to the CLKIN,
DATA and RSTIN pin and observing the outputs
of the selected card socket.
11. The CLKRUNA and CLKRUNB pins may be
set HI if the user desires to continue to send the
clock signal to a card socket after it has been
deselected. The card socket’s ENABLE pin
must be set HI for this function to work.
The user has the option of controlling the inputs
externally, rather than by using the on-board jumpers. To do this, the jumpers should be removed
and external signal sources (e.g. microcontroller
outputs) should be connected to the associated
terminals on the board.
The RSTIN, CLKIN, ENABLEA, ENABLEB,
VSELA, VSELB, CLKRUNA, CLKRUNB and
CSEL inputs all possess external 100kΩ pull down
resistors (R1 through R9) to prevent them from
floating. These resistors may be removed if the
inputs are controlled with an external signal
source.
LTC4558
Figure 1. Proper Measurement Equipment Setup
GND
VIN
Figure 2. Measuring Input or Output Ripple
3
LTC4558
4
LTC4558
5
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