MAX5168 Maxim Integrated Products, MAX5168 Datasheet - Page 10

• Manufacturer Part Number: MAX5168
• Description: 32-Channel Sample/Hold Amplifier
• Manufacturer: Maxim Integrated Products

www.DataSheet4U.com
The input of the MAX5168 feeds the inputs of 32 high-
impedance buffers. These buffers are what charge the
sample/hold capacitor through the multiplexer switch
resistance. The bias current of a selected buffer is
10µA, and this feeds into the 10pF input capacitance.
Figure 5 shows an equivalent input circuit. The bias cur-
rents of the other 31 sample and holds are very small in
comparison to the bias current of the selected channel.
The MAX5168 does not require a special power-up
sequence to avoid latchup. The device requires three
separate supply voltages for operation. However, when
one or two of the voltages are not available, DC-DC
charge-pump (switched-capacitor) converters provide
a simple, efficient solution. The MAX860 provides volt-
age doubling or inversion, ideal for conversions from
+5V to +10V or from +5V to -5V.
TRANSISTOR COUNT: 6961
32-Channel Sample/Hold Amplifier
with a Single Multiplexed Input
Figure 4. 64-Output Sample/Hold Circuit
10
______________________________________________________________________________________
A0–A4
A5
WR
INPUT
Input Drive Requirements
Powering the MAX5168
Chip Information
ADDR0–ADDR4
ADDR0–ADDR4
V
L
CONFIG
CONFIG
SELECT
SELECT
S/H
S/H
IN
IN
Figure 5. Input Equivalent Circuit
MAX5168
MAX5168
10µA, I
NH
= LOW
I
BIAS
10pF
C
IN
OUT0
OUT1
OUT30
OUT31
OUT32
OUT33
OUT62
OUT63