Switching Electrical Characteristics (continued)

(VDDA – VGNDA = 1.71V to 5.5V, VDDB – VGNDB = 4.5V to 5.5V, TA = TMIN to TMAX, unless otherwise noted. Typical values are

at VDDA – VGNDA = 3.3V, VDDB – VGNDB = 5V, VGNDA = VGNDB, and TA = +25°C.) (Note 8)

Note 3: All currents into the device are positive. All currents out of the device are negative. All voltages are referenced to their

respective ground (GNDA or GNDB), unless otherwise noted.

Note 7: The short circuit output current applies to the peak current just prior to foldback current limiting.

Note 8: Not production tested. Guaranteed by design.

Note 9: CMTI is the maximum sustainable common-mode voltage slew rate while maintaining the correct output states. CMTI

applies to both rising and falling common-mode voltage edges. Tested with the transient generator connected between

GNDA and GNDB. ΔVCM = 1kV.

Note 10: Capacitive load includes test probe and fixture capacitance.

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Driver Enable to Output Low

tDZL

RL = 500Ω, CL = 50pF, Figure 6

88

ns

Driver Disable Time from Low

tDLZ

RL = 500Ω, CL = 50pF, Figure 6

80

ns

Driver Disable Time from High

tDHZ

RL = 500Ω, CL = 50pF, Figure 5

80

ns

RECEIVER

Receiver Propagation Delay

tRPLH, tRPHL CL = 15pF, Figure 7 and 8 (Note 10)

68

ns

Receiver Output Skew

|tRPLH - tRPHL|

tRSKEW

CL = 15pF, Figure 7 and 8

(Note 10)

6

ns

Maximum Data Rate

DRMAX

20

Mbps

Receiver Enable to Output

High

tRZH

RL = 1kΩ, CL = 15pF, S2 closed,

Figure 9

20

ns

Receiver Enable to Output Low

tRZL

RL = 1kΩ, CL = 15pF, S1 closed,

Figure 9

30

ns

Receiver Disable Time From

Low

tRLZ

RL = 1kΩ, CL = 15pF, S1 closed,

Figure 9

20

ns

Receiver Disable Time From

High

tRHZ

RL = 1kΩ, CL = 15pF, S2 closed,

Figure 9

20

ns

MAX14938/MAX14939

RS-485 Transceivers with ±35kV ESD Protection

www.maximintegrated.com

Maxim Integrated │ 6