1. General description
The 74LVC1T45; 74LVCH1T45 are single bit, dual supply transceivers with 3-state
outputs that enable bidirectional level translation. They feature two 1-bit input-output ports
(A and B), a direction control input (DIR) and dual supply pins (V
CC(A)
and V
CC(B)
). Both
V
CC(A)
and V
CC(B)
can be supplied at any voltage between 1.2 V and 5.5 V making the
device suitable for translating between any of the low voltage nodes (1.2 V, 1.5 V, 1.8 V,
2.5 V, 3.3 V and 5.0 V). Pins A and DIR are referenced to V
CC(A)
and pin B is referenced
to V
CC(B)
. A HIGH on DIR allows transmission from A to B and a LOW on DIR allows
transmission from B to A.
The devices are fully specified for partial power-down applications using I
OFF
. The I
OFF
circuitry disables the output, preventing any damaging backflow current through the
device when it is powered down. In suspend mode when either V
CC(A)
or V
CC(B)
are at
GND level, both A port and B port are in the high-impedance OFF-state.
Active bus hold circuitry in the 74LVCH1T45 holds unused or floating data inputs at a valid
logic level.
2. Features and benefits
Wide supply voltage range:
V
CC(A)
: 1.2 V to 5.5 V
V
CC(B)
: 1.2 V to 5.5 V
High noise immunity
Complies with JEDEC standards:
JESD8-7 (1.2 V to 1.95 V)
JESD8-5 (1.8 V to 2.7 V)
JESD8C (2.7 V to 3.6 V)
JESD36 (4.5 V to 5.5 V)
ESD protection:
HBM JESD22-A114F Class 3A exceeds 4000 V
CDM JESD22-C101E exceeds 1000 V
Maximum data rates:
420 Mbps (3.3 V to 5.0 V translation)
210 Mbps (translate to 3.3 V))
140 Mbps (translate to 2.5 V)
75 Mbps (translate to 1.8 V)
60 Mbps (translate to 1.5 V)
Suspend mode
74LVC1T45; 74LVCH1T45
Dual supply translating transceiver; 3-state
Rev. 6 — 6 August 2012 Product data sheet