Datasheet

MAX1220/MAX1257/MAX1258
12-Bit, Multichannel ADCs/DACs with FIFO,
Temperature Sensing, and GPIO Ports
6 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(V
AVDD
= V
DVDD
= 2.7V to 3.6V (MAX1257), external reference V
REF
= 2.5V (MAX1257), V
AVDD
= 4.75V to 5.25V, V
DVDD
= 2.7V to V
AVDD
(MAX1220/MAX1258), external reference V
REF
= 4.096V (MAX1220/MAX1258), f
CLK
= 3.6MHz (50% duty cycle), T
A
= -40°C to +85°C,
unless otherwise noted. Typical values are at V
AVDD
= V
DVDD
= 3V (MAX1257), V
AVDD
= V
DVDD
= 5V (MAX1220/MAX1258), T
A
= +25°C.
Outputs are unloaded, unless otherwise noted.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
DIGITAL OUTPUT (EOC) (Note 14)
Output-Voltage Low V
OL
I
SINK
= 2mA 0.4 V
Output-Voltage High V
OH
I
SOURCE
= 2mA
V
DVDD
-
0.5
V
Three-State Leakage Current ±10 µA
Three-State Output
Capacitance
C
OUT
15 pF
DIGITAL OUTPUTS (GPIO_) (Note 14)
I
SINK
= 2mA 0.4
GPIOB_, GPIOC_ Output-
Voltage Low
I
SINK
= 4mA 0.8
V
GPIOB_, GPIOC_ Output-
Voltage High
I
SOURCE
= 2mA
V
DVDD
-
0.5
V
GPIOA_ Output-Voltage Low I
SINK
= 15mA 0.8 V
GPIOA_ Output-Voltage High I
SOURCE
= 15mA
V
DVDD
-
0.8
V
Three-State Leakage Current ±10 µA
Three-State Output
Capacitance
C
OUT
15 pF
POWER REQUIREMENTS (Note 15)
Digital Positive-Supply Voltage DV
DD
2.7 V
AVDD
V
Idle, all blocks shut down 0.2 4 µA
Digital Positive-Supply Current DI
DD
Only ADC on, external reference 1 mA
MAX1257 2.7 3.6
Analog Positive-Supply Voltage AV
DD
MAX1220/MAX1258 4.75 5.25
V
Idle, all blocks shut down 0.2 2 µA
f
SAMPLE
= 225ksps 2.8 4.2
Only ADC on,
external reference
f
SAMPLE
= 100ksps 2.6
Analog Positive-Supply Current AI
DD
All DACs on, no load, internal reference 1.5 4
mA
MAX1257, V
AVDD
= 2.7V -77
REF1 Positive-Supply
Rejection
PSRR
MAX1220/MAX1258, V
AVDD
= 4.75V -80
dB
MAX1257, V
AVDD
= 2.7V to
±0.1 ±0.5
DAC Positive-Supply Rejection PSRD
Output
code =
FFFhex
MAX1220/MAX1258,
V
AVDD
= 4.75V to 5.25V
±0.1 ±0.5
mV
MAX1257, V
AVDD
= 2.7V to
±0.06 ±0.5
ADC Positive-Supply Rejection PSRA
Full-
scale
input
MAX1220/MAX1258,
V
AVDD
= 4.75V to 5.25V
±0.06 ±0.5
mV