User Manual

ATA5756/ATA5757 [Preliminary]

4702D–RKE–02/04

4 ANT2 Emitter of antenna output stage

5 ANT1 Open collector antenna output

6 XTO2 Diode switch, used for FSK modulation

7 XTO1 Connection for crystal

8 VS Supply voltage See ESD protection circuitry (see Figure 12)

9 GND Ground See ESD protection circuitry (see Figure 12)

10 ENABLE

ENABLE input

If ENABLE is connected to GND and

the ASK or FSK pin is High, the device

stays in idle mode.

In normal operation ENABLE is left

open and ASK or FSK is used to enable

the device.

Pin Description

Pin Symbol Function Configuration

ANT1

ANT2

XTO2

210 µA

(FSK < 0.25V)

AND

(ENABLE > 1.7V)

XTO1

1.2k

1.5k

182 µA

ENABLE

150k

30 µA

(FSK >1.7 V ) OR

(ASK > 1.7 V)

250k