Figure 6.
GPIO connector circuit
2.3
Level translator: ST2378E
The
device is an 8-bit, dual supply, bidirectional level translator with ±15 kV ESD protection on I/Os at
VCC side. It is designed to interface data transfer between low voltage ASICs/PLDs and higher voltage systems.
Externally applied voltage, VCC and VL, set logic levels at both sides with the range specified as 1.71 V ≤ VL≤ 5.5
V and VL≤ VCC≤ 5.5 V. For proper operation, VCC should be set higher than VL.
Using a transmission-gate-based design, this device allows bidirectional asynchronous data transfer. This means
that each channel is allowed to have either VCC to VL or VL to VCC data transfer direction independently; no
direction pin is required.
The
device operates at a guaranteed data rate of 13 Mbps over the entire specified operating voltage
range. The OE pin allows the disable mode operation whereby the current consumption is reduced to less than 1
μA.
Table 4.
ST2378E details
Features
Description
Order code
ST2378ETTR
Package
20-TSSOP
Operating voltage
1.71 V to 5.5 V
As all the on-board sensors operate at 1.8 V, the voltage is shifted before communicating with the 40-pin GPIO
connector.
UM3076
Level translator: ST2378E
UM3076
-
Rev 1
page 7/38