Description – Rainbow Electronics AT77C102B User Manual
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5364A–BIOM–09/05
AT77C102B
3.
Description
The AT77C102B is part of the Atmel FingerChip monolithic fingerprint sensor family for which no
optics, no prism and no light source are required.
The AT77C102B is a single-chip, high-performance, low-cost sensor based on temperature
physical effects for fingerprint sensing.
The AT77C102B has a linear shape, which captures a fingerprint image by sweeping the finger
across the sensing area. After capturing several images, Atmel proprietary software can recon-
struct a full 8-bit fingerprint image.
The AT77C102B has a small surface combined with CMOS technology, and a Chip-on-Board
package assembly. These facts contribute to a low-cost device.
The device delivers a programmable number of images per second, while an integrated analog-
to-digital converter delivers a digital signal adapted to interfaces such as an EPP parallel port, a
USB microcontroller or directly to microprocessors. No frame grabber or glue interface is there-
fore necessary to send the frames. These facts make AT77C102B an easy device to include in
any system for identification or verification applications.
Table 3-1.
Absolute Maximum Ratings
()
Parameter
Symbol
Comments
Value
Positive supply voltage
V
CC
GND to 4.6
Note: Stresses beyond those listed
under “Absolute Maximum Ratings”
may cause permanent damage to the
device. These are stress ratings only
and functional operation of the device at
these or any other conditions beyond
those indicated in the operational
sections of this specification is not
implied. Exposure to absolute
maximum rating conditions for extended
periods may affect device reliability.
Temperature stabilization
power
TPP
GND to 4.6
Front plane
FPL
GND to V
CC
+0.5
Digital input voltage
RST PCLK
GND to V
CC
+0.5
Storage temperature
T
stg
-50 to +95
Lead temperature
(soldering, 10 seconds)
T
leads
Do not solder
Forbidden
Table 3-2.
Recommended Conditions Of Use
Parameter
Symbol
Comments
Min
Typ
Max
Unit
Positive supply voltage
V
CC
3V
3.3V
3.6V
V
Front plane
FPL
Must be grounded
GND
V
Digital input voltage
CMOS levels
V
Digital output voltage
CMOS levels
V
Digital load
C
L
50
pF
Analog load
C
A
R
A
Not connected
pF
k
Ω
Operating temperature range
T
amb
V grade
-40
°C to +85°C
°C
Maximum current on TPP
ITPP
0
100
mA