Document
ą
TLV1548ĆQ1
LOWĆVOLTAGE 10ĆBIT ANALOGĆTOĆDIGITAL CONVERTER
WITH SERIAL CONTROL AND 8 ANALOG INPUTS
SGLS172B − JUNE 2003 − REVISED APRIL 2008
D Qualified for Automotive Applications D ESD Protection Exceeds 2000 V Per
MIL-STD-883, Method 3015; Exceeds 200 V Using Machine Model (C = 200 pF, R = 0)
D Conversion Time ≤ 10 µs D 10-Bit-Resolution ADC D Programmable Power-Down
Mode . . . 1 µA
D Wide Range Single-Supply Operation of
2.7 V dc to 5.5 V dc
D Analog Input Range of 0 V to VCC D Built-in Analog Multiplexer with 8 Analog
Input Channels
D TMS320 DSP and Microprocessor SPI and
QSPI Compatible Serial Interfaces
D End-of-Conversion (EOC) Flag D Inherent Sample-and-Hold Function D Built-In Self-Test Modes
D Programmable Power and Conversion Rate D Asynchronous Start of Conversion for
Extended Sampling
D Hardware I/O Clock Phase Adjust Input
A0 A1 A2 A3 A4 A5 A6 A7 CSTART GND
DB PACKAGE (TOP VIEW)
1
20
2
19
3
18
4
17
5
16
6
15
7
14
8
13
9
12
10
11
VCC EOC I/O CLK DATA IN DATA OUT CS REF+ REF− FS INV CLK
description
The TLV1548 is a CMOS 10-bit switched-capacitor successive-approximation (SAR) analog-to-digital (A/D) converter. The device has a chip select (CS), input-output clock (I/O CLK), data input (DATA IN) and serial data output (DATA OUT) that provides a direct 4-wire synchronous serial peripheral interface (SPI, QSPI) port of a host microprocessor. When interfacing with a TMS320 DSP, an additional frame sync signal (FS) indicates the start of a serial data frame. The device allows high-speed data transfers from the host. The INV CLK input provides further timing flexibility for the serial interface.
In addition to a high-speed converter and versatile control capability, the device has an on-chip 11-channel multiplexer that can select any one of eight analog inputs or any one of three internal self-test voltages. The sample-and-hold function is automatic except for the extended sampling cycle, where the sampling cycle is started by the falling edge of asynchronous CSTART. At the end of the A/D conversion, the end-of-conversion (EOC) output goes high to indicate that the conversion is complete. The TLV1548 is designed to operate with a wide range of supply voltages with very low power consumption. The power saving feature is further enhanced with a software-programmed power-down mode and conversion rate. The converter incorporated in the device features differential high-impedance reference inputs that facilitate ratiometric conversion, scaling, and isolation of analog circuitry from logic and supply noise. A switched-capacitor design allows low-error conversion over the full operating temperature range.
The TLV1548 has eight analog input channels. The TLV1548Q is characterized for operation over the full automotive temperature range of −40°C to 125°C.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
SPI and QSPI are registered trademarks of Motorola, Inc.
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.
Copyright 2008 Texas Instruments Incorporated
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
1
TLV1548ĆQ1
ą
LOWĆVOLTAGE 10ĆBIT ANALOGĆTOĆDIGITAL CONVERTER
WITH SERIAL CONTROL AND 8 ANALOG INPUTS
SGLS172B − JUNE 2003 − REVISED APRIL 2008
functional block diagram
A0−A7 1−8 REF+ 14
Self-Test Reference
Sample and
Hold Function
CLOCK
10-Bit ADC (Switch Capacitors)
Analog MUX
Output Data Register
10-to-1 Data Selector
16 DATA OUT
13 REF−
17 DATA IN
Input Data Register
Control Logic and
I/O Counters
19 EOC
12 FS
15 CS 9 CSTART 11 INV CLK
18 I/O CLK
Terminals shown are for the DB package.
ORDERING INFORMATION{
TA
PACKAGE}
ORDERABLE PART NUMBER
TOP-SIDE MARKING
−40°C to 125°C SSOP − DB Tape and reel TLV1548QDBRQ1 1548Q1
† For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI web site at http://www.ti.com.
‡ Package drawings, thermal data, and symbolization are available at http://www.ti.com/packaging.
2
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
ą
TLV1548ĆQ1
LOWĆVOLTAGE 10ĆBIT ANALOGĆTOĆDIGITAL CONVERTER
WITH SERIAL CONTROL AND 8 ANALOG INPUTS
SGLS172B − JUNE 2003 − REVISED APRIL 2008
Terminal Functions
TERMINAL NAME NO.
A0−A3
1−4
A4−A7
5−8
CS
15
CSTART
9
DATA IN
17
DATA OUT 16
EOC
19
FS
12
GND
10
INV CLK
11
I/O
DESCRIPTION
I Analog inputs. The analog inputs are internally multiplexed. (For a source impedance greater than 1 kΩ, the asynchronous start should be used to increase the sampling time.)
I Chip select. A high-to-.