THVD1510 Datasheet, PDF (17/39 Pages) Texas Instruments – 5-V RS-485 Transceivers With 18-kV IEC ESD Protection

www.ti.com
THVD1510, THVD1512
THVD1550, THVD1551, THVD1552
SLLSEV1 – SEPTEMBER 2017
When the receiver enable pin, RE, is logic low, the receiver is enabled. When the differential input voltage
defined as V_ID = V_A – V_B is higher than the positive input threshold, V_TH+, the receiver output, R, turns high.
When V_ID is lower than the negative input threshold, V_TH-, the receiver output, R, turns low. If V_ID is between V_TH+
and V_TH- the output is indeterminate.
When RE is logic high or left open, the receiver output is high-impedance and the magnitude and polarity of V_ID
are irrelevant. Internal biasing of the receiver inputs causes the output to go failsafe-high when the transceiver is
disconnected from the bus (open-circuit), the bus lines are shorted to one another (short-circuit), or the bus is not
actively driven (idle bus).
DIFFERENTIAL INPUT
V_ID = V_A – V_B
V_TH+ < V_ID
V_TH- < V_ID < V_TH+
V_ID < V_TH-
X
X
Open-circuit bus
Short-circuit bus
Idle (terminated) bus
Table 6. Receiver Function Table for THVD1512 and THVD1552
ENABLE
RE
L
L
L
H
OPEN
L
L
L
OUTPUT
R
H
?
L
Z
Z
H
H
H
FUNCTION
Receive valid bus high
Indeterminate bus state
Receive valid bus low
Receiver disabled
Receiver disabled by default
Fail-safe high output
Fail-safe high output
Fail-safe high output
Copyright © 2017, Texas Instruments Incorporated
Submit Documentation Feedback
17
Product Folder Links: THVD1510 THVD1512 THVD1550 THVD1551 THVD1552