Rainbow Electronics MAX3022 - Manual (Page 11)

MAX3013–MAX3022
+1.2V to +3.6V, 0.1µA, 100Mbps,
8-Channel Level Translators
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Detailed Description
The MAX3013–MAX3022 logic-level translators provide
the level shifting necessary to allow 100Mbps data trans-
fer in a multivoltage system. Externally applied voltages,
V
CC and V L , set the logic levels on either side of the
device. Logic signals present on the V L side of the
device appear as a higher voltage logic signal on the
V
CC side of the device, and vice-versa. The MAX3013
bidirectional level translator allows data translation in
either direction (V
L ↔ V CC ) on any single data line. The
MAX3014–MAX3022 unidirectional translators level-shift
data in one direction (V
L → V CC or V CC → V L ) on any
single data line. The MAX3013–MAX3022 accept V L from
+1.2V to (V CC - 0.4V) and operate with V CC from +1.65V
to +3.6V, making them ideal for data transfer between
low-voltage ASICs/PLDs and higher voltage systems.
The MAX3013–MAX3022 feature an input enable mode
(EN) that reduces V
CC and V L supply currents to 0.1µA,
when in tristate mode. These devices operate at a
guaranteed data rate of 100Mbps for V
L > +1.8V.
Level Translation
For proper operation, ensure that +1.65V ≤ V CC ≤ +3.6V,
+1.2V ≤ V L ≤ (V CC - 0.4V). During power-up sequencing,
V L ≥ V CC does not damage the device. During power-
supply sequencing, when V CC is floating and V L is pow-
ering up, up to 40mA current can be sourced to each
load on the V
L side, yet the device does not latch up.
The maximum data rate depends heavily on the load
capacitance (see the Typical Operating Characteristics,
Rise/Fall Times), output impedance of the driver, and the
operating voltage range (see the Timing Characteristics).
Input Driver Requirements
The MAX3013–MAX3022 architecture is based on a
one-shot accelerator output stage (see Figure 5).
Accelerator output stages are always in tristate mode
except when there is a transition on any of the transla-
tors on the input side, either I/O V
L or I/O V CC . Then, a
short pulse is generated during which the accelerator
output stages become active and charge/discharge the
capacitances at the I/Os. Due to its bidirectional nature,
both input stages become active during the one-shot
pulse. This can lead to some current feeding into the
external source that is driving the translator. However,
this behavior helps to speed up the transition on the
driven side.
For proper operation, the external driver must meet the
following conditions: <25Ω output impedance and
>20mA output current. Figure 6 shows a graph of
Typical Input Current vs. Input Voltage.
Output Load Requirements
The MAX3013–MAX3022 I/O were designed to drive
CMOS inputs. Do not load the I/O lines with a resistive
load less than 25kΩ. Also, do not place an RC circuit at
the input of the MAX3013–MAX3022 to slow down the
edges. If a slower data rate is required, please see the
MAX3000E/MAX3001E logic-level translator.
For I 2 C™ level translation, please refer to the MAX3372E–
MAX3379E/MAX3390E–MAX3393E data sheet.
OV CC
V L
IV L
V CC
P
ONE-SHOT
N
ONE-SHOT
TYPICAL DRIVING ONE-CHANNEL ON V L SIDE
150Ω
4kΩ
IV CC
V L
OV L
V CC
TYPICAL DRIVING ONE-CHANNEL ON V
CC
SIDE
4kΩ
150Ω
N
ONE-SHOT
P
ONE-SHOT
Figure 5. MAX3013–MAX3022 Simplified Diagram (1 I/O line)
I 2 C is a trademark of Philips Corp. Purchase of I 2 C components
of Maxim Integrated Products, Inc. or one of its sublicensed
Associated Companies, conveys a license under the Philips I
2 C
Patent Rights to use these components in an I 2 C system, provid-
ed that the system conforms to the I 2 C Standard Specification
as defined by Philips.