LINEAR_DIMENSIONS LNDADC14

ADVANCE DATASHEET
D
LNDADC14
<4uA 14 Bit Pipeline ADC
GENERAL DESCRIPTION
The LNDADC14 is a very low current (typical 3.5uA in 14 bit
mode and 2.7uA in 10 bit mode) analog to digital converter
developed for low bandwidth battery operated portable
electronics applications. The LNDADC14 uses the latest
techniques in low current data converter design. These newly
derived techniques obsolete many of the existing low current
implementations with respect to their power per conversation
figure of merit (FOM).
The LNDADC14 operates from 2.7 to 3.6V Vin and operates
at a 2.5kHz clock rate. The LDSADC12 features a user
settable resolution from 8 to 14 bits to optimize power savings
(for example a signal may be sampled at 8 bits until a desired
signal is found to be present and then the resolution improved
to 14 bits to improve feature accuracy at the price of current
consumption for a period of time).
FEATURES
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2.7 to 3.6Vin operation
0 to 3.6V dynamic range
3.5uA typical current (14 bit sampling)
2.7uA typical current (10 bit sampling)
1.5 bit quantizer
Self correcting architecture
Eight (8) through fourteen (14) bit user adjustable
operation to save power
Fast startup (<100us)
<100nA in sleep mode
Operates from as little as 2.7V Vin
2.5kHz minimum sampling rate
>12 ENOB (14 bit operation)
DNL +/-0.45, INL +/-0.65
SPI Interface (independently enabled)
SELF CORRECTING 1.5 BIT QUANTIZER
The LNDADC14 utilizes a 1.5 bit self correcting and fully
differential internal analysis engine making it extremely
tolerant to noise, battery glitches, and comparator
metastability. An example of this self correcting capability is
shown in Figure 1 (this is an 8 bit example).
For extremely low current applications of limited bandwidth
(<1uA) the LNDADC14 may be utilized in a wakeup and sleep
mode due to its fast startup time. The LNDADC14 utilizes
<100nA of current in sleep mode.
The LNDADC14 features an ENOB of >12 in 14 bit mode and
>9 in 10 bit mode, an INL of +/-0.65 LSB and DNL of +/-0.45
LSB.
SELF CORRECTING EXAMPLE
Figure 1 – Self correcting behavior (here shown for 8 bit operation) of the 1.5
bit quantizer illustrates the robustness of the LNDADC14 to noise or
comparator metastability errors
APPLICATIONS
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Portable heart rate equipment
Portable fitness & wellness products
Non-critical diagnostics
Low bandwidth portable electronics
EXAMPLE WAVEFORMS
Figure 2 – Cycle by cycle waveforms of the LNDADC14
in 8 bit mode of operation from the internal pipeline
operation to digital output using 2.7uA.
 Linear Dimensions Semiconductor Inc.  22620 Ricardo Rd, Cupertino CA 95014 USA  tel 312.321.1810  fax 312.321.1830  www.lineardimensions.com 