MAX3226EAAE+T Maxim Integrated, MAX3226EAAE+T Datasheet - Page 10

• Manufacturer Part Number: MAX3226EAAE+T
• Description: RS-232 Interface IC
• Manufacturer: Maxim Integrated
• Series: MAX3224E, MAX3225E, MAX3226E, MAX3227E, MAX3244E, MAX3245Er

Specifications of MAX3226EAAE+T

• Data Rate: 250 Kbps
• Operating Supply Voltage: 3 V to 5.5 V
• Supply Current: 1 mA
• Operating Temperature Range: 0 C to + 70 C
• Function: Transceiver
• Number Of Drivers: 1
• Number Of I/os: 4
• Number Of Receivers: 1
• Propagation Delay Time Ns: 0.15 us
• Shutdown: Yes

±15kV ESD-Protected +2.5V to +5.5V
RS-232 Transceivers in UCSP and WLP
a larger nominal value. The capacitor’s equivalent series
resistance (ESR) usually rises at low temperatures and
influences the amount of ripple on V+ and V-.
In most circumstances, a 0.1µF V
is adequate. In applications that are sensitive to power-
Figure 5a. Human Body ESD Test Models
Figure 5b. Human Body Model Current Waveform
Figure 6a. IEC 1000-4-2 ESD Test Model
10
AMPERES
VOLTAGE
VOLTAGE
SOURCE
SOURCE
HIGH-
HIGH-
______________________________________________________________________________________
I
DC
DC
P
36.8%
100%
90%
10%
0
CHARGE-CURRENT-
CHARGE-CURRENT-
0
R
LIMIT RESISTOR
LIMIT RESISTOR
C
50MΩ TO 100MΩ
t
RL
R
C
1MΩ
100pF
150pF
C s
C s
Power-Supply Decoupling
CURRENT WAVEFORM
TIME
STORAGE
CAPACITOR
STORAGE
CAPACITOR
R
R
RESISTANCE
RESISTANCE
D
DISCHARGE
DISCHARGE
t
D
DL
1500Ω
330Ω
I r
CC
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
bypass capacitor
DEVICE
DEVICE
UNDER
UNDER
TEST
TEST
supply noise, use a capacitor of the same value as the
charge-pump capacitor C1. Connect bypass capaci-
tors as close to the IC as possible.
Figure 7 shows a transmitter output when exiting shut-
down mode. The transmitter is loaded with 3kΩ in par-
allel with 1000pF. The transmitter output displays no
ringing or undesirable transients as it comes out of
shutdown, and is enabled only when the magnitude of
V- exceeds approximately -3V.
The MAX3230E/AE and MAX3231E/AE maintain the
RS-232 ±5.0V minimum transmitter output voltage even
at high data rates. Figure 8 shows a transmitter loop-
back test circuit. Figure 9 shows a loopback test result
at 120kbps, and Figure 10 shows the same test at
250kbps. For Figure 9, the transmitter was driven at
120kbps into an RS-232 load in parallel with 1000pF.
For Figure 10, a single transmitter was driven at
250kbps and loaded with an RS-232 receiver in paral-
lel with 1000pF.
Figure 6b. IEC 1000-4-2 ESD Generator Current Waveform
Table 3. Required Capacitor Values
2.5 to 3.0
3.0 to 3.6
4.5 to 5.5
3.0 to 5.5
V
t r = 0.7ns to 1ns
CC
(V)
100%
90%
10%
I
C1, C
30ns
Transmitter Outputs when
BYPASS
0.047
0.22
0.22
0.1
60ns
(µF)
Exiting Shutdown
High Data Rates
C2, C3, C4 (µF)
0.22
0.33
0.1
1
t