Document
19-3425; Rev 0; 10/04
KIT ATION EVALU LE B A IL A AV
www.DataSheet4U.com
Single-Chip Global Positioning System Receiver Front-End
General Description Features
o Complete Single-Chip GPS Radio for 16.368MHz and 32.736MHz Floorplans o Single-Ended or Differential Outputs at 4.092MHz o Low 3.5dB Typical Noise Figure o No External IF SAW or Discrete Filters Required o On-Chip Temperature Sensor o 2.4V to 3.6V Operational Supply Voltage Range o Power Consumption as Low as 41mW at 2.4V o Wide -40°C to +85°C Operational Temperature Range
MAX2745
The MAX2745 complete single-chip global positioning system (GPS) RF front-end downconverter utilizes many innovative and leading-edge RF CMOS design techniques. This high-performance, state-of-the-art device consumes extremely low power and eliminates the need for costly SAW and bulky discrete IF filters. The MAX2745 incorporates a fully integrated low-noise amplifier (LNA) and mixer, IF section, digital sampler, and local oscillator synthesizer. The MAX2745 also provides a voltage supply for an external LNA. In addition, the MAX2745 features a voltage booster, which can extend the power-supply voltage to as low as 1.6V. The MAX2745 supports both 3rd overtone crystal designs in 32MHz and fundamental frequency crystal designs in 16MHz, as well as a TCXO implementation. In addition, the MAX2745 incorporates an on-chip temperature sensor and crystal oscillator with trimmed capacitors, resulting in a very accurate frequency and additional system cost savings. The MAX2745 is available in a space-saving 48-pin TQFP package and is specified for the extended (-40°C to +85°C) temperature range. The power consumption of this device is as low as 41mW at 2.4V.
Ordering Information
PART MAX2745ECM TEMP RANGE -40°C to +85°C PIN-PACKAGE 48 TQFP-EP*
*EP = Exposed paddle. Typical Operating Circuit appears at end of data sheet
Applications
In-Vehicle Navigation Systems (IVNSs)
XTALOUT
CP_OUT
XTALIN
VTUNE
Telematics (Vehicle/Asset Tracking and Inventory Management) Recreational Handheld/Walkie Talkies Geographical Information Systems (GISs) Emergency Roadside Assistance Emergency Response Systems Digital Cameras/Camcorders Consumer Electronics
48 RBIAS 1 CBIAS 2 VDD 3 VDD 4 GND 5 GND 6
47
46
45
44
43
42
41
40
39
38
SDATA
37 36 BPF_CTRL 35 ODS 34 CFS 33 COE 32 VDD 31 SCLK 30 GND 29 VOUT+ 28 VOUT27 VDD 26 GND 25 VDD 24
SHDN
Location-Based Services (PDAs and Accessories)
Block Diagram/ Pin Configuration
GND GND VDD VDD VDD
VSPORT LNA/MIXER RFIN 7 GND 8 VDD 9 BANDPASS FILTER IEXT_LNA 10 VDD 11 AGC_FIL 12 13 14 15 16 17 18 19 20 21 22 23 FILTER AUTOMATIC TUNING VOLTAGE BOOSTER AGC QUANTIZER VCO
VCXO
MAX2745
TEMPERATURE SENSOR
BIAS PFD DIVIDER CHG PUMP
XTAL_SSEL
XTAL_CSEL
BST_CTRL
TEST_EN
VDD_VB
VB_CS+
VB_CS-
CKOUT
DOUT
GND
VDD
VTO
________________________________________________________________ Maxim Integrated Products
VOUT
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
www.DataSheet4U.com
Single-Chip Global Positioning System Receiver Front-End MAX2745
ABSOLUTE MAXIMUM RATINGS
VDD to GND ...........................................................-0.3V to +3.7V Other Pins to GND......................................-0.3V to (VDD + 0.3V) RF LNA Input Power .......................................................+10dBm Continuous Power Dissipation (TA = +70°C) 48-Pin TQFP-EP (derate 12.5mW/°C above +70°C) ............1W Operating Temperature Range ...........................-40°C to +85°C
CAUTION! ESD SENSITIVE DEVICE Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Soldering Temperature (10s) ...........................................+300°C
DC ELECTRICAL CHARACTERISTICS
(MAX2745 EV kit, VDD = +2.4V to +3.6V, SHDN = GND, TA = -40°C to +85°C. Typical values are at VDD = +3.0V and TA = +25°C, unless otherwise noted.)
PARAMETER Supply Voltage Supply Current Optional External LNA Supply Current Logic-Input High Voltage Logic-Input Low Voltage Logic-Input Bias Current -10 VDD = +3.0V, TA = +25°C (Note 1) Shutdown mode VDD = +3.0V 2.0 0.5 +10 CONDITIONS MIN 2.4 20.5 11 10 TYP MAX 3.6 27 UNITS V mA µA mA V V µA
AC ELECTRICAL CHARACTERISTICS
(MAX2745 EV kit, VDD = +2.4V to +3.6V, SHDN = GND, TA = -40°C to +85°C. Typical values are at VDD = +3.0V and TA = +25°C, unless otherwise noted.)
PARAMETER GENERAL PERFORMANCE Maximum Conversion Gain Input Frequency Noise F.