MAX3223ECPP Maxim Integrated Products, MAX3223ECPP Datasheet - Page 7

• Manufacturer Part Number: MAX3223ECPP
• Description: RS-232 Interface IC
• Manufacturer: Maxim Integrated Products

Specifications of MAX3223ECPP

• Lead Free Status / Rohs Status: No

The MAX3221E/MAX3223E/MAX3243E’s internal power
supply consists of a regulated dual charge pump that
provides output voltages of +5.5V (doubling charge
pump) and -5.5V (inverting charge pump), over the
+3.0V to +5.5V V
in discontinuous mode: if the output voltages are less
than 5.5V, the charge pumps are enabled; if the output
voltages exceed 5.5V, the charge pumps are disabled.
Each charge pump requires a flying capacitor (C1, C2)
and a reservoir capacitor (C3, C4) to generate the V+
and V- supplies.
The transmitters are inverting level translators that con-
vert CMOS-logic levels to 5.0V EIA/TIA-232 levels. They
guarantee a 250kbps data rate with worst-case loads
of 3kΩ in parallel with 1000pF, providing compatibility
with PC-to-PC communication software such as
LapLink™. Transmitters can be paralleled to drive mul-
tiple receivers. The MAX3243E has been specifically
designed to drive serial mice. Figure 1 shows a com-
plete system connection. When FORCEOFF is driven to
ground, or the AutoShutdown circuitry senses invalid
voltage levels on all receiver inputs, the transmitters are
disabled and the outputs are forced into a high-imped-
ance state. When powered off or shut down, the output
can be driven up to ±12V. The transmitter inputs do not
have pull-up resistors.
LapLink is a trademark of Traveling Software.
±15kV ESD-Protected, 1µA, 3.0V to 5.5V, 250kbps,
_______________Detailed Description
TQFN
EP
—
—
MAX3221E
Dual Charge-Pump Voltage Converter
TSSOP
SSOP/
—
—
—
RS-232 Transceivers with AutoShutdown
CC
_______________________________________________________________________________________
TQFN
EP
range. The charge pumps operate
—
—
MAX3223E
PIN
TSSOP
SSOP/
DIP/
RS-232 Transmitters
—
—
—
TSSOP
SSOP/
SO/
—
—
—
MAX3243E
19, 20
25, 32
9, 16,
THIN
QFN
EP
R_OUTB
NAME
GND
N.C.
Figure 1. Interface Under Control of PMU
MANAGEMENT
CONTROLLER
CPU
KEYBOARD
Noninverting Complementary Receiver Outputs.
Always active.
No Connection. Not internally connected.
Exposed Paddle. Solder the exposed paddle to the
ground plane or leave unconnected.
POWER-
UNIT OR
Pin Description (continued)
WITH
UART
CHIP
INVALID
FORCEOFF
FORCEON
I/O
FUNCTION
MAX3243E
RS-232
7