5

5364C–BIOM–3/07

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

Digital input voltage

RST PCLK

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

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

V grade

-40

°C to +85°C°C

Maximum current on TPP

ITPP

0

100

mA