X60003CIG3-50 Intersil, X60003CIG3-50 Datasheet - Page 12

• Manufacturer Part Number: X60003CIG3-50
• Description: IC VOLT REF 2.5MV 20PPM SOT-23
• Manufacturer: Intersil
• Series: FGA™r

Specifications of X60003CIG3-50

• Reference Type: Series
• Voltage - Output: 5V
• Tolerance: ±2.5mV
• Temperature Coefficient: 20ppm/°C
• Voltage - Input: 5.1 ~ 9 V
• Number Of Channels: 1
• Current - Quiescent: 900nA
• Current - Output: 10mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: SOT-23-3, TO-236-3, Micro3™, SSD3, SST3
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Current - Cathode: -

Applications Information
FGA Technology
The X60003 voltage references use the floating gate
technology to create references with very low drift and
supply current. Essentially the charge stored on a
floating gate cell is set precisely in manufacturing. The
reference voltage output itself is a buffered version of
the floating gate voltage. The resulting reference device
has excellent characteristics which are unique in the
industry: very low temperature drift, high initial
accuracy, and almost zero supply current. Also, the
reference voltage itself is not limited by voltage
bandgaps or zener settings, so a wide range of
reference voltages can be programmed (standard
voltage settings are provided, but customer-specific
voltages are available).
The process used for these reference devices is a floating
gate CMOS process, and the amplifier circuitry uses
CMOS transistors for amplifier and output transistor
circuitry. While providing excellent accuracy, there are
limitations in output noise level and load regulation due
to the MOS device characteristics. These limitations are
addressed with circuit techniques discussed in other
sections.
Handling and Board Mounting
FGA references provide excellent initial accuracy and low
temperature drift at the expense of very little power
drain. There are some precautions to take to insure this
accuracy is not compromised. Excessive heat during
solder reflow can cause excessive initial accuracy drift, so
the recommended +260°C max temperature profile
should not be exceeded. Expect up to 1mV drift from the
solder reflow process.
FGA references are susceptible to excessive X-radiation
like that used in PC board manufacturing. Initial accuracy
can change 10mV or more under extreme radiation. If an
assembled board needs to be X-rayed, care should be
taken to shield the FGA reference device.
Nanopower Operation
Reference devices achieve their highest accuracy when
powered up continuously, and after initial stabilization
has taken place.
The X60003 is the first high precision voltage reference
with ultra low power consumption that makes it practical
to leave power-on continuously in battery operated
circuits. The X60003 consume extremely low supply
current due to the proprietary FGA technology. Supply
current at room temperature is typically 500nA which is 1
to 2 orders of magnitude lower than competitive devices.
Application circuits using battery power will benefit
greatly from having an accurate, stable reference which
essentially presents no load to the battery.
In particular, battery-powered data converter circuits
that would normally require the entire circuit to be
disabled when not in use can remain powered-up
12
X60003
between conversions as shown in Figure 33. Data
acquisition circuits providing 12 to 24-bits of accuracy
can operate with the reference device continuously
biased with no power penalty, providing the highest
accuracy and lowest possible long term drift.
Other reference devices consuming higher supply
currents will need to be disabled in between conversions
to conserve battery capacity. Absolute accuracy will
suffer as the device is biased and requires time to settle
to its final value, or, may not actually settle to a final
value as power-on time may be short.
Board Mounting Considerations
For applications requiring the highest accuracy, board
mounting location should be reviewed. Placing the device
in areas subject to slight twisting can cause degradation
of the accuracy of the reference voltage due to die
stresses. It is normally best to place the device near the
edge of a board, or the shortest side, as the axis of
bending is most limited at that location. Obviously
mounting the device on flexprint or extremely thin PC
material will likewise cause loss of reference accuracy.
Board Assembly Considerations
FGA references provide high accuracy and low
temperature drift but some PC board assembly
precautions are necessary. Normal Output voltage shifts
of 100µV to 1mV can be expected with Pb-free reflow
profiles or wave solder on multi-layer FR4 PC boards.
Precautions should be taken to avoid excessive heat or
extended exposure to high reflow or wave solder
temperatures, this may reduce device initial accuracy.
Post-assembly x-ray inspection may also lead to
permanent changes in device output voltage and should
be minimized or avoided. If x-ray inspection is required,
it is advisable to monitor the reference output voltage to
verify excessive shift has not occurred. If large amounts
of shift are observed, it is best to add an X-ray shield
consisting of thin zinc (300µm) sheeting to allow clear
imaging, yet block x-ray energy that affects the FGA
reference.
FIGURE 33. BATTERY-POWERED DATA CONVERTER
V
IN
= +6V TO 9V
CIRCUITS
GND
X60003
V
IN
V
OUT
0.001µF
SERIAL
BUS
10µF
REF IN
ENABLE
SCK
SDAT
A/D CONVERTER
0.01µF
12 TO 24-bit
March 21, 2011
FN8137.3