EVALUATION KIT AVAILABLE MAX2837 General Description The MAX2837 direct-conversion zero-IF RF transceiver is designed specifically for 2.3GHz to 2.7GHz wireless broadband systems. The MAX2837 completely integrates all circuitry required to implement the RF transceiver function, providing RF-to-baseband receive path; and baseband-to-RF transmit path, VCO, frequency synthesizer, crystal oscillator, and baseband/control interface. The device includes a fast-settling sigma-delta RF synthesizer with smaller than 20Hz frequency steps and a crystal oscillator, which allows the use of a low-cost crystal in place of a TCXO. The transceiver IC also integrates circuits for on-chip DC offset cancellation, I/Q error, and carrier-leakage detection circuits. Only an RF bandpass filter (BPF), crystal, RF switch, PA, and a small number of passive components are needed to form a complete wireless broadband RF radio solution. The MAX2837 completely eliminates the need for an external SAW filter by implementing on-chip monolithic filters for both the receiver and transmitter. The baseband filters along with the Rx and Tx signal paths are optimized to meet stringent noise figure and linearity specifications. The device supports up to 2048 FFT OFDM and implements programmable channel filters for 1.75MHz to 28MHz RF channel bandwidths. The transceiver requires only 2μs Tx-Rx switching time, which includes frequency transient settling. The IC is available in a small, 48-pin thin QFN package measuring only 6mm x 6mm x 0.8mm. Applications ●● ●● ●● ●● ●● 802.16-2004 Fixed WiMAX® Korea Wibro and 802.16e Mobile WiMAX Dual Mode™ WiMAX/802.11b/g Wi-Fi Proprietary Wireless Broadband Systems 4G/LTE Systems 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Features ●● 2.3GHz to 2.7GHz Wideband Operation ●● Complete RF Transceiver, PA Driver, and Crystal Oscillator • 0dBm Linear OFDM Transmit Power • -70dBr Tx Spectral Emission Mask • 2.3dB Rx Noise Figure • Tx/Rx I/Q Error and LO Leakage Detection • Monolithic Low-Noise VCO with -39dBc Integrated Phase Noise • Programmable Tx I/Q Lowpass Anti-Aliasing Filter • Sigma-Delta Fractional-N PLL with 20Hz Step Size • 45dB Tx Gain-Control Range • 94dB Receive Gain-Control Range • 60dB Analog RSSI Instantaneous Dynamic Range • 4-Wire SPI Digital Interface • I/Q Analog Baseband Interface • Digitally Tuned Crystal Oscillator • On-Chip Digital Temperature Sensor Read-Out ●● +2.7V to +3.6V Transceiver Supply ●● Low-Power Shutdown Current ●● Small 48-Pin Thin QFN Package (6mm x 6mm x 0.8mm) Ordering Information PART TEMP RANGE MAX2837ETM+TD -40°C to +85°C PIN-PACKAGE 48 TQFN-EP* *EP = Exposed pad. +Denotes a lead(Pb)-free/RoHS-compliant package. Pin Configuration appears at end of data sheet. Dual Mode is a trademark of Maxim Integrated Products, Inc. WiMAX is a registered certification mark and registered service mark of the WiMAX Forum. 19-0806; Rev 2; 7/15 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Absolute Maximum Ratings VCCLNA, VCCTXMX, VCCTXPAD, VCCDIG, VCCCP, VCCXTAL, VCCVCO, VCCRXVGA, VCCRXFL and VCCRXMX to GND...................................................................-0.3V to +3.9V B1–B7, TXRF_, CS, SCLK, DIN, DOUT, TXBBI_, TXBBQ_, RXHP, RXBBI_, RXBBQ_, RSSI, ENABLE, BYPASS, CPOUT_, CLOCKOUT, XTAL1, XTAL2, RXRF_,RXENABLE, TXENABLE to GND.............. -0.3V to (Operating VCC + 0.3V) RXBBI_, RXBBQ_, RSSI, BYPASS, CPOUT_, DOUT, CLOCKOUT, PABIAS Short-Circuit Duration............................................. 10s RF Input Power...............................................................+10dBm Continuous Power Dissipation (TA = +70°C) 48-Pin Thin QFN (derates 37mW/°C above +70°C)......2.96W Operating Temperature Range............................ -40°C to +85°C Junction Temperature.......................................................+150°C Storage Temperature Range............................. -65°C to +160°C Lead Temperature (soldering, 10s).................................. +260°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. DC Electrical Characteristics (MAX2837 evaluation kit: VCC_ = 2.7V to 3.6V, Rx set to the maximum gain; CS = high, RXHP = SCLK = DIN = low, RSSI and clock output buffer are off, no signal at RF inputs, all RF inputs and outputs terminated into 50Ω, receiver baseband outputs are open; 90mVRMS differential I and Q signals applied to I, Q baseband inputs of transmitter in transmit mode, fREF = 40MHz, registers set to recommended settings and corresponding test mode, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = 2.8V, fLO = 2.5GHz, and TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER Supply Voltage CONDITIONS VCC_ MIN Shutdown mode, TA = +25°C 35 91 110 170 Rx calibration mode 135 160 Tx calibration mode 110 135 1.0 1.20 0.85 D9:D8 = 01 in A4:A0 = 00100 1.1 D9:D8 = 10 in A4:A0 = 00100 1.2 D9:D8 = 11 in A4:A0 = 00100 1.35 Tx Baseband Input Bias Current Source current 0.5 10 LOGIC INPUTS: ENABLE, TXENABLE, RXENABLE, SCLK, DIN, CS, B7:B1, RXHP Digital Input-Current High, IIH Digital Input-Current Low, IIL www.maximintegrated.com µA 45 145 DC-coupled Digital Input-Voltage Low, VIL V Tx mode, TA = +25°C Tx Baseband Input CommonMode Voltage Operating Range Digital Input-Voltage High, VIH UNITS 3.6 Rx mode D9:D8 = 00 in A4:A0 = 00100 Rx I/Q Output Common-Mode Voltage MAX 10 Standby mode Supply Current TYP 2.7 VCC - 0.4 mA V 1.2 V 20 µA V 0.4 V -1 +1 µA -1 +1 µA Maxim Integrated │ 2 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver DC Electrical Characteristics (continued) (MAX2837 evaluation kit: VCC_ = 2.7V to 3.6V, Rx set to the maximum gain; CS = high, RXHP = SCLK = DIN = low, RSSI and clock output buffer are off, no signal at RF inputs, all RF inputs and outputs terminated into 50Ω, receiver baseband outputs are open; 90mVRMS differential I and Q signals applied to I, Q baseband inputs of transmitter in transmit mode, fREF = 40MHz, registers set to recommended settings and corresponding test mode, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = 2.8V, fLO = 2.5GHz, and TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS LOGIC OUTPUTS: DOUT Digital Output-Voltage High, VOH Digital Output-Voltage Low, VOL Sourcing 100µA VCC - 0.4 Sinking 100µA V 0.4 V AC Electrical Characteristics—Rx MODE (MAX2837 evaluation kit: VCC_ = 2.8V, fRF = 2.502GHz, fLO = 2.5GHz; receiver baseband I/Q outputs at 90mVRMS (-21dBV), fREF = 40MHz, ENABLE = RXENABLE = CS = high, TXENABLE = SCLK = DIN = low, with power matching for the differential RF pins using the typical applications and registers set to default settings and corresponding test mode, TA = +25°C, unless otherwise noted. Lowpass filter is set to 10MHz RF channel BW. Unmodulated single-tone RF input signal is used, unless otherwise indicated.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS 2.7 GHz RECEIVER SECTION: LNA RF INPUT TO BASEBAND I/Q OUTPUTS RF Input Frequency Range 2.3 Peak-to-Peak Gain Variation over RF Input Frequency Range Tested at band edges and band center RF Input Return Loss All LNA gain settings Total Voltage Gain RF Gain Steps Gain Change Settling Time Baseband Gain Range TA = -40°C to +85°C Maximum gain, B7:B1 = 0000000 Minimum gain, B7:B1 = 1111111 www.maximintegrated.com dB 13 dB 99 5 From max RF gain to max RF gain - 8dB 8 From max RF gain to max RF gain - 16dB 16 From max RF gain to max RF gain - 32dB 32 Any RF or baseband gain change; gain settling to within P1dB of steady state; RXHP = 1 0.2 Any RF or baseband gain change; gain settling to within P0.1dB of steady state; RXHP = 1 2 From maximum baseband gain (B5:B1 = 00000) to minimum baseband gain (B5:B1 = 11111), TA = -40°C to +85°C Baseband Gain Minimum Step Size DSB Noise Figure 90 0.8 13 dB dB µs 58 62 2 Voltage gain R 65dB with max RF gain (B7:B6 = 00) 2.3 Voltage gain = 50dB with max RF gain - 8dB (B7:B6 = 01) 5.5 Voltage gain = 45dB with max RF gain - 16dB (B7:B6 = 10) 17 Voltage gain = 15dB with max RF gain - 32dB (B7:B6 = 11) 27 66 dB dB dB Maxim Integrated │ 3 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver AC Electrical Characteristics—Rx MODE (continued) (MAX2837 evaluation kit: VCC_ = 2.8V, fRF = 2.502GHz, fLO = 2.5GHz; receiver baseband I/Q outputs at 90mVRMS (-21dBV), fREF = 40MHz, ENABLE = RXENABLE = CS = high, TXENABLE = SCLK = DIN = low, with power matching for the differential RF pins using the typical applications and registers set to default settings and corresponding test mode, TA = +25°C, unless otherwise noted. Lowpass filter is set to 10MHz RF channel BW. Unmodulated single-tone RF input signal is used, unless otherwise indicated.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS Max RF gain (B7:B6 = 00) -37 Max RF gain - 8dB (B7:B6 = 01) -29 Max RF gain - 16dB (B7:B6 = 10) -21 Max RF gain - 32dB (B7:B6 = 11) -4 Over passband frequency range; at any gain setting; 1dB compression point 2.5 Max RF gain (B7:B6 = 00), AGC set for -65dBm wanted signal -11 Max RF gain - 8dB (B7:B6 = 01), AGC set for -55dBm wanted signal -8 Max RF gain - 16dB (B7:B6 = 10), AGC set for -40dBm wanted signal -6 Max RF gain - 32dB (B7:B6 = 11), AGC set for -30dBm wanted signal +16 I/Q Phase Error 50kHz baseband output; 1s variation 0.15 Degrees I/Q Gain Imbalance 50kHz baseband output; 1s variation 0.1 dB Rx I/Q Output Load Impedance (R || C) Minimum differential resistance 10 kΩ Maximum differential capacitance 5 pF I/Q Output DC Droop After switching RXHP to 0; average over 1µs after any gain change, or 2µs after receive enabled with 100Hz interval ACcoupling, 1s variation ±1 mV/ms I/Q Static DC Offset No RF input signal; measure at 3µs after receive enable; RXHP = 1 for 0 to 2µs and set to 0 after 2µs, 1s variation ±1 mV Loopback Gain (for Receiver I/Q Calibration) Transmitter I/Q input to receiver I/Q output; transmitter B6:B1 = 000011, receiver B5:B1 = 10100 programmed through SPI In-Band Input P-1dB Maximum Output Signal Level Out-of-Band Input IP3 (Note 2) dBm VP-P dBm -4.5 0 +4.5 dB RECEIVER BASEBAND FILTERS Baseband Filter Rejection At 15MHz 57 At 20MHz 75 At > 40MHz 90 RXHP = 1 (used before AGC completion) Baseband Highpass Filter Corner Frequency www.maximintegrated.com D5:D4 = 00 RXHP = 0 (used after D5:D4 = 01 AGC completion) address D5:D4 = 10 A4:A0 = 01110 D5:D4 = 11 dB 650 0.1 kHz 1 30 100 Maxim Integrated │ 4 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver AC Electrical Characteristics—Rx MODE (continued) (MAX2837 evaluation kit: VCC_ = 2.8V, fRF = 2.502GHz, fLO = 2.5GHz; receiver baseband I/Q outputs at 90mVRMS (-21dBV), fREF = 40MHz, ENABLE = RXENABLE = CS = high, TXENABLE = SCLK = DIN = low, with power matching for the differential RF pins using the typical applications and registers set to default settings and corresponding test mode, TA = +25°C, unless otherwise noted. Lowpass filter is set to 10MHz RF channel BW. Unmodulated single-tone RF input signal is used, unless otherwise indicated.) (Note 1) PARAMETER RF Channel BW Supported by Baseband Filter Baseband Gain Ripple Baseband Group Delay Ripple CONDITIONS MIN TYP A4:A0 = 00010 serial bits D7:D4 = 0000 1.75 A4:A0 = 00010 serial bits D7:D4 = 0001 2.25 A4:A0 = 00010 serial bits D7:D4 = 0010 3.5 A4:A0 = 00010 serial bits D7:D4 = 0011 5.0 A4:A0 = 00010 serial bits D7:D4 = 0100 5.5 A4:A0 = 00010 serial bits D7:D4 = 0101 6.0 A4:A0 = 00010 serial bits D7:D4 = 0110 7.0 A4:A0 = 00010 serial bits D7:D4 = 0111 8.0 A4:A0 = 00010 serial bits D7:D4 = 1000 9.0 A4:A0 = 00010 serial bits D7:D4 = 1001 10.0 A4:A0 = 00010 serial bits D7:D4 = 1010 12.0 A4:A0 = 00010 serial bits D7:D4 = 1011 14.0 A4:A0 = 00010 serial bits D7:D4 = 1100 15.0 A4:A0 = 00010 serial bits D7:D4 = 1101 20.0 A4:A0 = 00010 serial bits D7:D4 = 1110 24.0 A4:A0 = 00010 serial bits D7:D4 = 1111 28.0 0 to 2.3MHz for BW = 5MHz 1.3 0 to 4.6MHz for BW = 10MHz 1.3 0 to 2.3MHz for BW = 5MHz 90 0 to 4.6MHz for BW = 10MHz 50 MAX UNITS MHz dBP-P nsP-P Baseband Filter Rejection for 5MHz RF Channel BW At 3.3MHz 7 At > 21MHz 85 Baseband Filter Rejection for 10MHz RF Channel BW At 6.7MHz 7 At > 41.6MHz 85 RLOAD ≥ 10kΩ 0.4 V 2.2 V 30 mV/dB dB dB RSSI RSSI Minimum Output Voltage RSSI Maximum Output Voltage RSSI Slope RSSI Output Settling Time www.maximintegrated.com RLOAD ≥ 10kΩ To within 3dB of steady state +32dB signal step 200 -32dB signal step 800 ns Maxim Integrated │ 5 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver AC Electrical Characteristics—Tx MODE (MAX2837 evaluation kit: VCC_ = 2.8V, TA = +25°C, fRF = 2.502GHz, fLO = 2.5GHz; fREF = 40MHz, ENABLE = TXENABLE = CS = high, and RXENABLE = SCLK = DIN = low, with power matching for the differential RF pins using the Typical Operating Circuit. Lowpass filter is set to 10MHz RF channel BW, 90mVRMS sine and cosine signal (or 90mVRMS 64QAM 1024-FFT OFDMA FUSC I/Q signals wherever OFDM is mentioned) applied to baseband I/Q inputs of transmitter (differential DC-coupled).) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS 2.7 GHz TRANSMIT SECTION: Tx BASEBAND I/Q INPUTS TO RF OUTPUTS RF Output Frequency Range 2.3 Peak-to-Peak Gain Variation over RF Band Output optimally matched over 200MHz RF BW 2.5 dB Total Voltage Gain Max gain; at unbalanced 50Ω balun output 12 dB 0 dBm 8 dB 45 dB Without calibration by modem, and excludes modem I/Q imbalance; POUT = 0dBm 45 dBc B1 1 B2 2 B3 4 B4 8 B5 16 B6 16 Relative to 0dBm output power; without calibration by modem -35 dBc Minimum differential resistance 100 kΩ Maximum differential capacitance 0.5 pF Baseband Frequency Response for 5MHz RF Channel BW 0 to 2.3MHz 0.2 At > 25MHz 80 Baseband Frequency Response for 10MHz RF Channel BW 0 to 4.6MHz 0.2 At > 17MHz 80 0 to 2.3MHz (BW = 5MHz) 20 0 to 4.6MHz (BW = 10MHz) 12 Maximum Output Power over OFDM signal conforming to spectral emission mask and Frequency for Any Given 200MHz -36dB EVM after I/Q imbalance calibration by modem Band (Note 3) RF Output Return Loss Given 200MHz band in the 2.3GHz to 2.7GHz range, for which the matching has been optimized RF Gain Control Range Unwanted Sideband Suppression RF Gain-Control Binary Weights Carrier Leakage Tx I/Q Input Impedance (R || C) Baseband Group Delay Ripple www.maximintegrated.com dB dB dB ns Maxim Integrated │ 6 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver AC Electrical Characteristics—Frequency Synthesis (MAX2837 evaluation kit: VCC_ = 2.8V, fLO = 2.5GHz, fREF = 40MHz, ENABLE = CS = high, SCLK = DIN = low, PLL loop bandwidth = 120kHz, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS 2.7 GHz FREQUENCY SYNTHESIZER RF Channel Center Frequency 2.3 Channel Center Frequency Programming Minimum Step Size 20 Hz MHz Charge-Pump Comparison Frequency 11 40 Reference Frequency Range 11 40 Reference Frequency Input Levels Reference Frequency Input Impedance (R || C) AC-coupled to XTAL2 pin 80 800 MHz mVP-P Resistance (XTAL2 pin) 10 kΩ Capacitance (XTAL2 pin) 1 pF Programmable Reference Divider Values 1 Closed-Loop Integrated Phase Noise Loop BW = 120kHz; integrate phase noise from 200Hz to 5MHz, charge-pump comparison frequency = 40MHz Charge-Pump Output Current 2 4 -39 dBc On each differential side 1.6 mA fOFFSET = 0 to 1.8MHz -40 fOFFSET > 7MHz -80 -85 dBc Turnaround LO Frequency Error Relative to steady state; measured 35µs after Tx-Rx or Rx-Tx switching instant, and 4µs after any receiver gain changes ±50 Hz Temperature Range over Which VCO Maintains Lock Relative to the ambient temperature TA, as long as the VCO lock temperature range is within operating temperature range TA ±40 °C Close-In Spur Level Reference Spur Level fOFFSET = 1.8MHz to 7MHz Reference Output Clock Divider Values -70 1 2 Output Clock Drive Level 20MHz output, 1x drive setting 1.5 Output Clock Minimum Load Impedance (R || C) Resistance 10 Capacitance 2 www.maximintegrated.com dBc VP-P kΩ pF Maxim Integrated │ 7 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver AC Electrical Characteristics—Miscellaneous Blocks (MAX2837 evaluation kit: VCC_ = 2.8V, fREF = 40MHz, ENABLE = CS = high, SCLK = DIN = low, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS PA BIAS DAC: CURRENT MODE Numbers of Bits 6 Bits Minimum Output Sink Current D5:D0 = 000000 in A4:A0 = 11100 0 µA Maximum Output Sink Current D5:D0 = 111111 in A4:A0 = 11100 310 µA Compliance Voltage Range Turn-On Time 0.8 Excludes programmable delay of 0 to 7µs in steps of 0.5µs DNL 2.0 V 200 ns 1 LSB VCC -0.2 V 0.1 V ns PA BIAS DAC: VOLTAGE MODE Output High Level 10mA source current Output Low Level 10mA sink current Turn-On Time Excludes programmable delay of 0 to 7µs in steps of 0.5µs 200 Maximum capacitance, A4:A0 = 11000, D6:D0 =1111111 15.5 Minimum capacitance, A4:A0 = 11000, D6:D0 =0000000 0.5 CRYSTAL OSCILLATOR On-Chip Tuning Capacitance Range pF On-Chip Tuning Capacitance Step Size 0.12 pF ON-CHIP TEMPERATURE SENSOR Digital Output Code Read-out at DOUT pin through SPI A4:A0 = 00111, D4:D0 TA = +25°C 01111 TA = +85°C 11101 TA = -40°C 00001 AC Electrical Characteristics—Timing (MAX2837 evaluation kit: VCC_ = 2.8V, fLO = 2.5GHz, fREF = 40MHz, ENABLE = CS = high, SCLK = DIN = low, PLL loop bandwidth = 120kHz, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS SYSTEM TIMING Turnaround Time Tx Turn-On Time (from Standby Mode) www.maximintegrated.com Measured from Tx or Rx to Tx Rx enable rising edge; signal settling to within 0.5dB of steady state Tx to Rx, RXHP = 1 Measured from Tx enable rising edge; signal settling to within 0.5dB of steady state 2 µs 2 2 µs Maxim Integrated │ 8 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver AC Electrical Characteristics—Timing (continued) (MAX2837 evaluation kit: VCC_ = 2.8V, fLO = 2.5GHz, fREF = 40MHz, ENABLE = CS = high, SCLK = DIN = low, PLL loop bandwidth = 120kHz, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS Tx Turn-Off Time (to Standby Mode) From Tx enable falling edge Rx Turn-On Time (from Standby Mode) Measured from Rx enable rising edge; signal settling to within 0.5dB of steady state Rx Turn-Off Time (to Standby Mode) From Rx enable falling edge MIN TYP MAX UNITS 0.1 µs 2 µs 0.1 µs 4-WIRE SERIAL-INTERFACE TIMING (See Figure 1) SCLK Rising Edge to CS Falling Edge Wait Time tCSO 6 ns Falling Edge of CS to Rising Edge of First SCLK Time tCSS 6 ns tDS DIN to SCLK Setup Time 6 ns tDH 6 ns tCH 6 ns tCL 6 ns Last Rising Edge of SCLK to Rising Edge of CS or Clock to Load Enable Setup Time tCSH 6 ns CS High Pulse Width tCSW 20 ns Time Between Rising Edge of CS and the Next Rising Edge of SCLK tCS1 6 ns Clock Frequency fCLK DIN to SCLK Hold Time SCLK Pulse-Width High SCLK Pulse-Width Low Rise Time Fall Time SCLK Falling Edge to Valid DOUT tR 45 MHz ns tF fCLK / 10 fCLK / 10 ns tD 12.5 ns Note 1: Min and max limits guaranteed by test above TA = +25°C and guaranteed by design and characterization at TA = -40°C. The power-on register settings are not production tested. Recommended register setting must be loaded after VCC is supplied. Note 2: Two tones at +25MHz and +39MHz offset with -35dBm/tone. Measure IM3 at 1MHz. Note 3: Gain adjusted over max gain and max gain - 3dB. Optimally matched over given 200MHz band. www.maximintegrated.com Maxim Integrated │ 9 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Typical Operating Characteristics (MAX2837 evaluation kit: VCC_ = 2.8V, fLO = 2.5GHz, 10MHz channel 16E UL/DL WiMax signal, fREF = 40MHz, ENABLE = CS = high, RXHP = SCLK = DIN = low, TA = +25°C, unless otherwise noted.) 0 LNA = MAX LNA = MAX - 8dB LNA = MAX - 16dB 2.4 2.5 2.6 RF FREQUENCY (GHz) EVM (%) 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 12 MAX2837 toc03 MAX2837 toc06 18 LNA = MAX - 32dB 20 10 8 6 0.3 4 2 0 8 16 24 BASEBAND VGA CODE -50 LNA = MAX -90 -80 -70 -60 -50 -40 -30 -20 -10 PIN (dBm) 0 Rx EMISSION SPECTRUM AT LNA INPUT -60 -70 -80 fOFFSET = 10MHz 0 32 WiMAX EVM WITH OFDM JAMMER vs. OFFSET FREQUENCY PIN = -60dBm 32 Rx EVM vs. PIN 14 0.6 8 16 24 BASEBAND VGA CODE 22 16 0.9 0 2.7 0 LNA = MAX -16dB 1.2 MAX2837 toc07 2.3 32 Rx IN-BAND OUTPUT V1dB vs. BASEBAND GAIN SETTING (dBm) -1 8 16 24 BASEBAND VGA CODE EVM (%) LNA = MAX - 32dB 0 1.5 Rx IN-BAND OUTPUT V1dB (VRMS) MAX2837 toc04 1 LNA = MAX - 32dB 0 MAX2837 toc08 3.6 LNA = MAX - 16dB 20 8/3LO 3.0 3.3 SUPPLY VOLTAGE (V) 0 40 2LO 2.7 2 Rx VOLTAGE GAIN VARIATION (dB) LNA = MAX 5 Rx VOLTAGE GAIN VARIATION vs. RF FREQUENCY -2 10 MAX2837 toc05 85 LNA = MAX - 8dB 8LO 87 15 60 LNA = MAX - 8dB 89 LNA = MAX - 16dB 20 LNA = MAX 4LO 91 25 LNA = MAX - 8dB 80 Rx VOLTAGE GAIN (dB) TA = +25°C 30 Rx VOLTAGE GAIN vs. BASEBAND GAIN SETTING 100 4/3LO CURRENT (mA) 93 TA = -40°C LNA = MAX - 32dB 35 NOISE FIGURE (dB) TA = +85°C 95 40 MAX2837 toc01 97 NOISE FIGURE vs. BASEBAND VGA GAIN SETTING MAX2837 toc02 Rx CURRENT vs. SUPPLY VOLTAGE -90 -100 -110 -120 -130 -65 -55 -45 -35 MIN LNA GAIN RBW = 300kHz -140 fOFFSET = 20MHz -25 -150 DC 26.5GHz PJAMMER (dBm) www.maximintegrated.com Maxim Integrated │ 10 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Typical Operating Characteristics (continued) (MAX2837 evaluation kit: VCC_ = 2.8V, fLO = 2.5GHz, 10MHz channel 16E UL/DL WiMax signal, fREF = 40MHz, ENABLE = CS = high, RXHP = SCLK = DIN = low, TA = +25°C, unless otherwise noted.) LNA = MAX LNA = MAX - 8dB 1.5 0V 1.45V 1.0 LNA = MAX - 16dB 2.4 2.6 2.8 RF FREQUENCY (GHz) 0 3.0 Rx RSSI STEP RESPONSE (-40dB SIGNAL STEP) MAX2837 toc12 350 3V -120 -100 -80 -60 -40 -20 INPUT POWER (dBm) LPF GROUP DELAY (ns) 0V 200ns/div Rx LPF GROUP DELAY vs. FREQUENCY CHANNEL BW = 5MHz 300 1.5V 0 CHANNEL BW = 8MHz 250 CHANNEL BW = 9MHz 200 CHANNEL BW = 10MHz 150 0 200ns/div 0 2 4 6 8 10 12 FREQUENCY (MHz) 145 52 39 14 16 0 1σ/div Tx OUTPUT POWER vs. RF FREQUENCY 1 TA = +25°C 140 VCC = 3V, 3.6V 0 Tx POWER (dBm) CURRENT (mA) TA = +85°C MEAN: 0mV STD: 0.977mV SAMPLE SIZE: 1006 13 Tx CURRENT vs. SUPPLY VOLTAGE 150 65 26 100 50 0.45V HISTOGRAM: Rx STATIC DC OFFSET 78 MAX2837 toc16 2.2 MAX2837 toc15 2.0 0.45V LNA = MAX - 32dB MAX2837 toc14 0.5 LNA = MAX 3V 2.0 -30 -40 MAX2837 toc10 2.5 MAX2837 toc13 LNA = MAX - 8dB, LNA = MAX - 16dB MAX2837 toc11 CW TONE -10 -20 Rx RSSI STEP RESPONSE (+40dB SIGNAL STEP) RSSI VOLTAGE vs. INPUT POWER 3.0 MAX2837 toc09 LNA = MAX - 32dB RSSI VOLTAGE (V) INPUT RETURN LOSS (dB) 0 INPUT RETURN LOSS vs. RF FREQUENCY -1 VCC = 2.7V -2 TA = -40°C 135 2.7 www.maximintegrated.com 3.0 3.3 SUPPLY VOLTAGE (V) 3.6 -3 2.3 2.4 2.5 2.6 RF FREQUENCY (GHz) 2.7 Maxim Integrated │ 11 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Typical Operating Characteristics (continued) (MAX2837 evaluation kit: VCC_ = 2.8V, fLO = 2.5GHz, 10MHz channel 16E UL/DL WiMax signal, fREF = 40MHz, ENABLE = CS = high, RXHP = SCLK = DIN = low, TA = +25°C, unless otherwise noted.) -1.5 -2.0 10 35 60 TEMPERATURE (°C) RF 4/3RF RBW = 1MHz 2RF 8/3RF -30 1.8 EVM (%) -50 16/3RF -60 EVM vs. Tx OUTPUT POWER 2.0 4RF -40 1.6 1.4 -70 1.2 -80 MAX2837 toc19 -40°C +25°C -50 +85°C 0 8 16 24 32 40 48 Tx VGA GAIN CODE 56 64 PHASE NOISE vs. OFFSET FREQUENCY -60 -70 -80 -90 -100 -110 -120 -130 -140 -90 26.5GHz -30 -24 -18 -12 -6 OUTPUT POWER (dBm) PLL SETTLING TIME FROM SHUTDOWN 500Hz/div -2.5kHz 0s www.maximintegrated.com 1ms CRYSTAL OFFSET FREQUENCY (Hz) 2.5kHz 1.0 0 800 700 600 500 400 300 200 100 0 -100 -200 -300 -400 -500 -600 -700 -800 -150 0.001 0.01 0.1 1 OFFSET FREQUENCY (MHz) 10 CRYSTAL OFFSET FREQUENCY vs. CTUNE BITS KYOCERA (CX-3225SB) MAX2837 toc24 DC MAX2837 toc23 -100 +85°C -30 -50 5MHz/div Tx TRANSMIT SPECTRUM FROM DC TO 26.5GHz -20 (dBm) 85 PHASE NOISE (dBc/Hz) -15 MAX2837 toc21 -40 0 -10 -20 -40 MAX2837 toc20 -3.0 -10 MAX2837 toc22 -2.5 +25°C FORBIDDEN CODE 10dB/div (dBm) -1.0 -40°C 0 Tx POWER (dBm) POUT = -3dBm EVM = 1.35% fRF = 2.5GHz Tx POUT vs. GAIN SETTING 10 MAX2837 toc18 Tx VGA SET TO MAX - 3dB -0.5 Tx POWER (dBm) Tx OUTPUT SPECTRUM Tx OUTPUT POWER vs. TEMPERATURE MAX2837 toc17 0 0 10 20 30 40 50 60 70 80 90 100110120130 CTUNE (DIGITAL BITS) Maxim Integrated │ 12 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Block Diagram/Typical Operating Circuit B2 TXRF+ TXRF- Rx/Tx GAIN CONTROL B1 1 RXBBI- RXBBI+ RXHP VCCRXFL TXBBI- TXBBI+ TXBBQ+ TXBBQ- VCCRXMX VCCRXVGA 39 38 37 36 IMUX MAX2837 2 35 TO RSSI MUX RSSI 3 QMUX 34 4 33 5 TEMP SENSOR RSSI 90 6 IMUX QMUX 32 31 0 SERIAL INTERFACE 7 AM DETECTOR 8 RSSI MUX 30 29 SCLK 9 28 10 27 11 SERIAL INTERFACE 12 VCCTXMX 13 14 PLL CRYSTAL OSCILLATOR/ BUFFER 15 16 17 SERIAL INPUTS 18 26 25 19 20 21 22 23 RXBBQ+ RXBBQ- Rx Q OUTPUTS B6 Rx/Tx GAIN CONTROL B7 Rx GAIN CONTROL RSSI DIN SERIAL INPUTS CS SERIAL INPUTS DOUT SERIAL OUTPUT VCCVCO BYPASS GNDVCO ENABLE MODE CONTROL 24 CPOUT- Tx OUTPUT Rx/Tx GAIN CONTROL B3 40 Rx I OUTPUTS CPOUT+ Rx/Tx GAIN CONTROL 41 GNDCP VCCTXPAD 42 VCCCP B4 43 VCCDIG Rx/Tx GAIN CONTROL 44 VCCXTAL RXRF- 45 XTAL1 RXRF+ 46 XTAL2 Rx/Tx GAIN CONTROL 47 CLOCKOUT Rx INPUT B5 Rx BASEBAND HPF CONTROL Tx INPUTS SCLK GNDRXLNA 48 PABIAS VCCRXLNA + TXENABLE RXENABLE MODE CONTROL PLL LOOP FILTER REFERENCE CLOCK BUFFER OUTPUT www.maximintegrated.com Maxim Integrated │ 13 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Pin Description PIN NAME 1 VCCRXLNA 2 GNDRXLNA LNA Ground 3 B5 4 RXRF+ 5 RXRF- 6 B4 7 VCCTXPAD 8 FUNCTION LNA Supply Voltage. Bypass with a capacitor as close as possible to the pin. Receiver and Transmitter Gain-Control Logic Input Bit 5 LNA Differential Inputs. Inputs are internally DC-coupled. An external shunt inductor and series capacitors match the inputs to 100Ω differential. Receiver and Transmitter Gain-Control Logic Input Bit 4 Supply Voltage for Power-Amplifier Driver. Bypass with a capacitor as close as possible to the pin. B3 Receiver and Transmitter Gain-Control Logic Input Bit 3 9 B2 Receiver and Transmitter Gain-Control Logic Input Bit 2 10 TXRF+ 11 TXRF- 12 B1 13 VCCTXMX 14 15 16 PABIAS SCLK Power-Amplifier Driver Differential Output. PA driver output is internally matched to a 100I differential. The pins have internal DC-blocking capacitors. Receiver and Transmitter Gain-Control Logic Input Bit 1 Transmitter Upconverter Supply Voltage. Bypass with a capacitor as close as possible to the pin. Transmit PA Bias DAC Output Serial-Clock Logic Input of 4-Wire Serial Interface (See Figure 1) CLOCKOUT Reference Clock Buffer Output 17 XTAL2 Crystal or Reference Clock Input. AC-couple a crystal or a reference clock to this analog input. 18 XTAL1 Connection for Crystal-Oscillator Off-Chip Capacitors. When using an external reference clock input, leave XTAL1 unconnected. 19 VCCXTAL 20 Crystal-Oscillator Supply Voltage. Bypass with a capacitor as close as possible to the pin. VCCDIG Digital Circuit Supply Voltage. Bypass with a capacitor as close as possible to the pin. 22 GNDCP Charge-Pump Circuit Ground 23 CPOUT+ 24 CPOUT- Differential Charge-Pump Output. Connect the frequency synthesizer’s loop filter between CPOUT+ and CPOUT-. (See the Typical Operating Circuit.) 25 ENABLE Operation Mode Logic Input. See Table 1 for operating modes. 26 GNDVCO VCO Ground 27 BYPASS On-Chip VCO Regulator Output Bypass. Bypass with a 1µF capacitor to GND. Do not connect other circuitry to this point. 28 VCCVCO VCO Supply Voltage. Bypass with a capacitor as close as possible to the pin. 21 29 30 VCCCP DOUT PLL Charge-Pump Supply Voltage. Bypass with a capacitor as close as possible to the pin. Data Logic Output of 4-Wire Serial Interface (See Figure 1) CS Chip-Select Logic Input of 4-Wire Serial Interface (See Figure 1) 31 DIN Data Logic Input of 4-Wire Serial Interface (See Figure 1) 32 RSSI RSSI or Temperature Sensor Multiplexed Analog Output 33 B7 Receiver Gain-Control Logic Input Bit 7 34 B6 Receiver and Transmitter Gain-Control Logic Input Bit 6 35 RXBBQ- 36 RXBBQ+ 37 RXBBI- 38 RXBBI+ 39 VCCRXVGA 40 41 RXHP VCCRXFL www.maximintegrated.com Receiver Baseband Q-Channel Differential Outputs. In Tx calibration mode, these pins are the LO leakage and sideband detector outputs. Receiver Baseband I-Channel Differential Outputs. In Tx calibration mode, these pins are the LO leakage and sideband detector outputs. Receiver VGA Supply Voltage Receiver Baseband AC-Coupling Highpass Corner Frequency Control Logic Input Receiver Baseband Filter Supply Voltage Maxim Integrated │ 14 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Pin Description (continued) PIN NAME 42 TXBBI- 43 TXBBI+ 44 TXBBQ+ 45 TXBBQ- 46 VCCRXMX FUNCTION Transmitter Baseband I-Channel Differential Inputs Transmitter Baseband Q-Channel Differential Inputs Receiver Downconverters Supply Voltage. Bypass with a capacitor as close as possible to the pin. 47 TXENABLE 48 RXENABLE Rx Mode Control Logic Input. See Table 1 for operating modes. EP EP Tx Mode Control Logic Input. See Table 1 for operating modes. Exposed Paddle. Connect to the ground plane with multiple vias for proper operation and heat dissipation. Do not share with any other pin grounds and bypass capacitors’ ground. Table 1. Operating Mode Table LOGIC PINS REGISTER SETTING ENABLE RXENABLE TXENABLE D1:D0 A4:A0 = 10000 MODE CIRCUIT BLOCK STATES Rx PATH Tx PATH PLL, VCO, LO GEN CALIBRATION SECTIONS ON CLOCK OUT On Clock-Out 1 0 0 0 0 Off Off Off None Shutdown 0 0 0 0 X Off Off Off None Off Standby 1 0 0 0 1 Off* Off* On None On Rx 1 1 0 0 1 On Off On None On Tx 1 0 1 0 1 Off On On None On Rx Calibration 1 1 0 1 1 On Tx Baseband Buffer On Tx Calibration 1 0 1 1 1 On AM Detector, Rx I/Q Buffers On On Off (Except (Except Upconverters) LNA) Off On (Except PA Driver) *Blocks of the transceiver can be selectively enabled through SPI. Detailed Description Modes of Operation internal programmable registers. If the supply voltage is applied, the registers are loaded and retained. The modes of operation for the MAX2837 are clock-out, shutdown, transmit, receive, transmitter calibration, and receiver calibration. See Table 1 for a summary of the modes of operation. The logic input pins—ENABLE (pin 25), TXENABLE (pin 47), and RXENABLE (pin 48)—control the various modes. When the parts are active, various blocks can be shut down individually through SPI. Standby Mode Shutdown Mode Receive (Rx) Mode The MAX2837 features a low-power shutdown mode. Current drain is the minimum possible with the supply voltages applied. In shutdown mode, all circuit blocks are powered down, except the 4-wire serial bus and its www.maximintegrated.com The standby mode is used to enable the frequency synthesizer block while the rest of the device is powered down. In this mode, PLL, VCO, and LO generator are on, so that Tx or Rx modes can be quickly enabled from this mode. These and other blocks can be selectively enabled in this mode. In receive mode, all Rx circuit blocks are powered on and active. Antenna signal is applied; RF is downconverted, filtered, and buffered at Rx BB I and Q outputs. The slowcharging Tx circuits are in a precharged “idle-off” state for fast Rx-to-Tx turnaround time. Maxim Integrated │ 15 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver DON'T CARE DOUT BIT 1 DIN BIT 2 BIT 5 BIT 6 BIT 13 BIT 14 SCLK tDS tCH tCL tCS1 CS tCSO tCSS tDH tCSH tCSW SPI REGISTER WRITE DON'T CARE DOUT BIT 6 BIT 13 BIT 14 tD DIN BIT 1 BIT 2 BIT 5 DON'T CARE SCLK CS SPI REGISTER READ Figure 1. 4-Wire SPI Serial-Interface Timing Diagram Transmit (Tx) Mode Clock-Out Only In transmit mode, all Tx circuit blocks are powered on. The external PA is powered on after a programmable delay using the on-chip PA bias DAC. The slow-charging Rx circuits are in a precharged “idle-off” state for fast Tx-to-Rx turnaround time. In clock-out mode, the entire transceiver is off except the divided reference clock output on the CLKOUT pin and the clock divider, which remains on. www.maximintegrated.com Maxim Integrated │ 16 MAX2837 Temperature Sensor Readout Through DOUT Pin To estimate chip temperature, on-chip temperature sensor is enabled by programming Address 9 D<1> = 1. The procedure is as follows: 1) Enable temp-sensor by setting Address 9 D<1> = 1. Roughly 100µs to 1ms time is needed to let the temperature sensor output settle to within 5 to 1 degrees. 2) To trigger temperature sensor ADC, program Address 9 D<0> from “0” to “1”. The ADC will acquire the 5-bit logic output in 2µs, temperature sensor needs to be ON (Address 9 D<1> = 1) to maintain the ADC logic output. Note that the ADC trigger should happen AFTER the temp sensor is enabled to get the correct result. Therefore, step 1 and step 2 of this procedure should be carried out on two separate SPI programming events separated by the temp sensor settling time. 3) Note that after the ADC latches its output and you desire to retake another temp sensor temperature reading value, the ADC has to be retriggered to reacquire a new temp sensor value (assuming the temp sensor is already enabled). To do so, program Address 9 D<0> from “1” to “0” then from “0” to “1”. After the ADC latches it digital output in 2µs it shuts off. 4) To read the 5-bit logic output through DOUT pin, apply 4-wire SPI readout programming sequence to Address 7. VAS Operating Procedure After power-up, program Address 22 D<1> = 0 such that VAS frequency acquisition starts from VCO band 15, it reduces the worst-case acquisition time by half. VAS acquisition starts after Address 17 is programmed (i.e. rising edge of CSB), it takes the worst-case 896µs to acquire lock. 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Wireless LAN or MAN systems do not switch channel frequency often, die temperature may change quite a bit over time and makes PLL out of lock. To relock PLL as soon as possible, the user can program Address 22 D<1> = 1 after the first power-up frequency acquisition. VAS starts from the previous frequency subband and should relock PLL within 112µs. VAS Readout The selected VCO subband, Vtune ADC output and VAS accomplished (VASA) signal can be read out through DOUT pin by programming Address 9 D<7:5> = 010 and corresponding Address 26 D<9:6>. VCO Subband Selection Through SPI For very fast band selection operation, the user can characterize the mapping between VCO frequencies and corresponding subbands during factory calibration. After programming Address 22 D<0> = 0, the VCO subband can be selected by Address 23 D<4:0>. Programmable Registers and 4-Wire SPI Interface The MAX2837 includes 32 programmable 16-bit registers. The most significant bit (MSB) is the read/write selection bit. The next 5 bits are register address. The 10 least significant bits (LSBs) are register data. Register data is loaded through the 4-wire SPI/MICROWIRE®-compatible serial interface. Data at DIN is shifted in MSB first and is framed by CS. When CS is low, the clock is active, and input data is shifted at the rising edge of the clock. During the read mode, register data selected by address bits is shifted out to DOUT at the falling edges of the clock. At the CS rising edge, the 10-bit data bits are latched into the register selected by address bits. See Figure 1. The register values are preserved in shutdown mode as long as the power-supply voltage is maintained. However, every time the power-supply voltage is turned on, the registers are reset to the default values. Note that default register states are not guaranteed, and the user should always reprogram all registers after power-up. MICROWIRE is a registered trademark of National Semiconductor Corp. www.maximintegrated.com Maxim Integrated │ 17 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 2. Recommended Register Settings ADDRESS D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 HEX 0 0 1 0 1 0 1 0 0 0 0 150 1 0 0 0 0 0 0 0 0 1 0 002 2 0 1 1 1 1 1 0 1 0 0 1F4 3 0 1 1 0 1 1 1 0 0 1 1B9 4 0 0 0 0 0 0 1 0 1 0 00A 5 0 0 1 0 0 0 0 0 0 0 080 6 0 0 0 0 0 0 0 1 1 0 006 7 0 0 0 0 0 0 0 0 0 0 000 8 0 0 1 0 0 0 0 0 0 0 080 9 0 0 0 0 0 1 1 0 0 0 018 10 0 0 0 1 0 1 1 0 0 0 058 11 0 0 0 0 0 1 0 1 1 0 016 12 1 0 0 1 0 0 1 1 1 1 24F 13 0 1 0 1 0 1 0 0 0 0 150 14 0 1 1 1 0 0 0 1 0 1 1C5 15 0 0 1 0 0 0 0 0 0 1 081 16 0 0 0 0 0 1 1 1 0 0 01C 17 0 1 0 1 0 1 0 1 0 1 155 18 0 1 0 1 0 1 0 1 0 1 155 19 0 1 0 1 0 1 0 0 1 1 153 20 1 0 0 1 0 0 0 0 0 1 241 21 0 0 0 0 1 0 1 1 0 1 02D 22 0 1 1 0 1 0 1 0 0 1 1A9 23 1 0 0 1 0 0 1 1 1 1 24F 24 0 1 1 0 0 0 0 0 0 0 180 25 0 1 0 0 0 0 0 0 0 0 100 26 1 1 1 1 0 0 1 0 1 0 3CA 27 1 1 1 1 1 0 0 0 1 1 3E3 28 0 0 1 1 0 0 0 0 0 0 0C0 29 1 1 1 1 1 1 0 0 0 0 3F0 30 0 0 1 0 0 0 0 0 0 0 080 31 0 0 0 0 0 0 0 0 0 0 000 www.maximintegrated.com Maxim Integrated │ 18 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 3. Address 0, RXRF Register 1 (Default = 150HEX) DATA BITS DEFAULT DESCRIPTION D9 0 D8:D3 101010 D2 0 Enables RX quadrature generation, except for shut down mode. 1 = Enable 0 = Disabled D1 0 Enables RX Mixer, except for shut down mode. 1 = Enable 0 = Disabled D0 0 Enables LNA, except for shut down mode. 1 = Enable 0 = Disabled Sets the center frequency of LNA output LC tank. 0 = Band 2.3~2.5GHz 1 = Band 2.5~2.7GHz Set to recommended value. Table 4. Address 1, RXRF Register 2 (Default = 002HEX) DATA BITS D9:D5 DEFAULT 00000 DESCRIPTION RX LO IQ calibration SPI control. Active when Address 8 D<9> = 1. Serves as trim word of fuse links independent of Address 8 D<9>. 00000 = +4.0° phase error (default) (Q lags I signal by 94°). … 01111 = 0.0° phase error. … 11111 = -4.0° deg phase error (Q lags I signal by 86°). Adjusts the LNA gain by SPI. Active when Address 8 D<0> = 1. 000 = MAX gain (default) 100 = MAX-8dB 010 = MAX-16dB 110 = MAX-24dB 011 = MAX-32dB 111 = MAX-40dB D4:D2 000 D1 1 LNA output tank de_Q resistance tuning in ‘Down’ process. 0 = Nominal 1 = Increase ~2dB gain in down process (default) D0 0 LNA output LC tank center frequency tuning in ‘Down’ process. 0 = Nominal (default) 1 = Down process www.maximintegrated.com Maxim Integrated │ 19 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 5. Address 2, LPF Register 1 (Default = 1F4HEX) DATA BITS D9:D8 D7:D4 DEFAULT 01 1111 DESCRIPTION Fine-tune the LPF cutoff frequency. 00 = -10% 01 = Nominal (default) 10 = Nominal 11 = +10% Sets the LPF RF Bandwidth. 0000 = 1.75MHz 0001 = 2.5MHz 0010 = 3.5MHz 0011 = 5.0MHz 0100 = 5.5MHz 0101 = 6.0MHz 0110 = 7.0MHz 0111 = 8.0MHz 1000 = 9.0MHz 1001 = 10.0MHz 1010 = 12.0MHz 1011 = 14.0MHz 1100 = 15.0MHz 1101 = 20.0MHz 1110 = 24.0MHz 1111 = 28.0MHz (default) D3:D2 01 Sets the mode of the lowpass filter block. Active when Address 6 D<9> = 1. 00 = Rx Calibration 01 = Rx LPF (default) 10 = Tx LPF 11 = LPF Trim D1 0 Enables the TX input buffer, except for shutdown mode. 1 = Enabled 0 = Disabled D0 0 Enables the lowpass filter, except for shutdown mode. 1 = Enabled 0 = Disabled www.maximintegrated.com Maxim Integrated │ 20 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 6. Address 3, LPF Register 2 (Default = 1B9HEX) DATA BITS DEFAULT D9:D7 011 D6:D0 0111001 DESCRIPTION Tx output (real pole) common-mode voltage adjustment. 000 = 1.00 V 001 = 1.05 010 = 1.10 011 = 1.15 (default) 100 = 1.20 101 = 1.25 110 = 1.30 111 = Not allowed Set to recommended value. Table 7. Address 4, LPF Register 3 and VGA Register 1 (Default = 00AHEX) DATA BITS DEFAULT DESCRIPTION D9:D8 00 Sets the RX VGA output common-mode voltage. 00 = 0.9V (default) 01 = 1.0V 10 = 1.1V 11 = 1.25V D7:D6 00 Set to recommended value. D5 0 RXVGA output MUX and buffer enable, except for shutdown mode. 1 = Enable 0 = Disabled D4 0 Enables RxVGA, except for shutdown mode. 1 = Enable 0 = Disabled D3:D0 1010 Set to recommended value. Table 8. Address 5, VGA Register 2 (Default = 080HEX) DATA BITS DEFAULT D9:D6 0010 D5 D4:D0 0 00000 www.maximintegrated.com DESCRIPTION Set to recommended value. RX baseband output select. Used to select RX mode and TX calibration mode output. 0 = RXVGA (default) 1 = TX AM detector for TX calibration mode. Sets attenuation in the RxVGA. Active when Address 8 D<1 > = 1. 00000 = MAX gain (default) 00001 = MAX - 2dB … 11111 = MIN gain Maxim Integrated │ 21 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 9. Address 6, VGA Register 3 and RX_TOP SPI bits (Default = 006HEX) DATA BITS DEFAULT DESCRIPTION D9 0 LPF mode mux, LPF_MODE_SEL = 1. 0 = Normal operation 1 = Operating mode is programmed Address 2 D3:D2 D8 0 RSSI operating mode during RX mode. 0 = Off when RXHP = 0 1 = Independent of RXHP D7 0 RSSI pin output MUX. 0 = Select RSSI 1 = Select Temperature sensor. D6 0 RSSI enable, except in shutdown mode. 0 = Disable RSSI 1 = Enable RSSI. D5:D0 000110 Set to recommended value. Table 10. Address 7, Temperature Sensor 5 bit ADC outputs (Default = 000HEX) DATA BITS DEFAULT D9:D5 00000 Set to Zeros DESCRIPTION D4:D0 00000 Directly connected to Temp Sensor ADC’s 5 bit outputs, can be read out by selecting RD_ ENABLE for this register. See the Temperature Sensor Readout Through DOUT Pin section in the Detailed Description. Table 11. Address 8, RX_TOP SPI bits and RX_BIAS SPI (Default = 080HEX) DATA BITS DEFAULT D9 0 D8:D2 0100000 D1 0 Mux VGA gain control bits from SPI. 0 = VGA gain to be controlled by external pins. 1= VGA gain to be controlled by SPI. D0 0 Mux LNA gain control bits from SPI. 0 = LNA gain to be controlled by external pins. 1 = LNA gain to be controlled by SPI www.maximintegrated.com DESCRIPTION RX IQ calibration DAC MUX between trim word and SPI. 0 = Select mux trim word 1 = Select mux SPI Set to recommended value. Maxim Integrated │ 22 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 12. Address 9, RX_TOP SPI bits (Default = 018HEX) DATA BITS DEFAULT D9:D8 00 Set to recommended value. D7:D5 00 DOUT pin output MUX select. 000 = SPI output (default) 001 = PLL lock detect and test output by Address 21 D9:D7. Set Address 21 D9:D7 = 000 for lock detect output. D4 1 DOUT pin pullup enable. 0 = Open drain 1 = CMOS (default) D3 1 DOUT pin output drive select. 0 = 1x (dly<4.4ns) 1 = 4x (dly<3.1ns, default) D2 0 Set to recommended value. D1 0 Temp sensor comparator and clock enable. 0 = Disable (default) 1 = Enable 0 Temp sensor ADC trigger. 0 = Not trigger ADC readout 1 = Trigger ADC readout, ADC is disabled automatically after readout finishes. See the Temperature Sensor Readout Through DOUT Pin section in the Detailed Description. D0 DESCRIPTION Table 13. Address 10, TX_TOP SPI register 1 (Default = 058HEX) DATA BITS DEFAULT D9:D6 0001 DESCRIPTION Set to recommended value. 011 Adjust the bandwidth of TX AM detector baseband filter. 000 = Default +12% … 011 = Default bandwidth … 111 = Default – 16% D2:D1 00 TX AM detector baseband gain control. 00 = Default minimum gain 01 = +10dB 10 = +20dB 11 = +30dB D0 0 Set to recommended value. D5:D3 www.maximintegrated.com Maxim Integrated │ 23 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 14. Address 11, TX_TOP SPI register 2 (Default = 016HEX) DATA BITS DEFAULT D0 0 D4:D1 1011 D0 0 DESCRIPTION AM detector SPI enable. 0 = Disable AM detector 1 = Enable AM detector in all modes except shutdown. Sets the TX mixer V2I gain. 0000 = MAX gain 0001 = MAX gain – 0.5dB … 1011 = MAX gain – 5.5dB (default) … 1111 = MAX gain – 7.5dB Set to recommended value. Table 15. Address 12, HPFSM register 1 bits (Default = 24FHEX) DATA BITS D9:D7 D6:D4 D3:D2 D1:D0 DEFAULT DESCRIPTION 100 Sets the RXVGA 600kHz highpass corner duration triggered by B7 and B6 switching. 000 = 0µs 001 = 0.8µs 010 = 1.6µs 011 = 2.4µs 100 = 3.2µs (default) 101 = 4.0µs 110 = 4.8µs 111 = stay “1” 100 Sets the RXVGA 600kHz highpass corner duration triggered by RXEN rising edge. 000 = 0µs 001 = 0.8µs 010 = 1.6µs 011 = 2.4µs 100 = 3.2µs (default) 101 = 4.0µs 110 = 4.8µs 111 = stay “1” 11 Sets the RXVGA 10MHz highpass corner duration triggered by B7 and B6 switching. 00 = 0µs 01 = 0.4µs 10 = 0.8µs 11 = 1.2µs (default) 11 Sets the RXVGA 10MHz highpass corner duration triggered by RXEN rising edge. 00 = 0µs 01 = 0.4µs 10 = 0.8µs 11 = 1.2µs (default) www.maximintegrated.com Maxim Integrated │ 24 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 16. Address 13, HPFSM register 2 bits (Default = 150HEX) DATA BITS D9:D7 D6:D4 D3:D2 D1:D0 DEFAULT DESCRIPTION 100 Sets the RXVGA 600kHz highpass corner duration triggered by B7 and B6 switching. 000 = 0µs 001 = 0.8µs 010 = 1.6µs 011 = 2.4µs 100 = 3.2µs (default) 101 = 4.0µs 110 = 4.8µs 111 = stay “1” 100 Sets the RXVGA 600kHz highpass corner duration triggered by RXEN rising edge. 000 = 0µs 001 = 0.8µs 010 = 1.6µs 011 = 2.4µs 100 = 3.2µs (default) 101 = 4.0µs 110 = 4.8µs 111 = stay “1” 11 Sets the RXVGA 10MHz highpass corner duration triggered by B7 and B6 switching. 00 = 0µs 01 = 0.4µs 10 = 0.8µs 11 = 1.2µs (default) 11 Sets the RXVGA 10MHz highpass corner duration triggered by RXEN rising edge. 00 = 0µs 01 = 0.4µs 10 = 0.8µs 11 = 1.2µs (default) www.maximintegrated.com Maxim Integrated │ 25 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 17. Address 14, HPFSM register 3 bits (Default = 1C5HEX) DATA BITS DEFAULT D9 0 Selects the RXVGA HPFSM operating mode. 0 = Mode #1 1 = Mode #2 which makes use of pin RXHP. D8 1 RXVGA HPFSM retriggered by B7 and B6. 0 = Disable 1 = Enable (default) 11 RXVGA highpass corner on-hold selection only during MODE2 when RXHP = 1. 00 = 1kHz 01 = 30kHz 10 = 100kHz 11 = 600kHz (default) 00 Selects the RXVGA final highpass corner. 00 = 100Hz (default) 01 = 1kHz 10 = 30kHz 11 = 100kHz 01 Sets the RXVGA HPCa and HPCd rising edge delay for 100kHz/30kHz/1kHz/100Hz highpass corner. 00 = 0µs 01 = 0.2µs (default) 10 = 0.4µs 11 = 0.6µs 01 RXVGA 1kHz highpass corner duration triggered by B7 and B6 switching. 00 = 0µs 01 = 3.2µs (default) 10 = 6.4µs 11 = 9.6µs D7:D6 D5:D4 D3:D2 D1:D0 DESCRIPTION Table 18. Address 15, HPFSM Register 4 Bits (Default = 081HEX) DATA BITS DEFAULT D9:D8 00 Set to recommended value. D7 1 Controls DOUT three-state to be dependent on CSB. 1 = Dout is three-state when CSB is Hi (default) 0 = Dout is not three-state and is independent on CSB D6 0 Sequence bypass during RXHP 1-->0 transition. 0 = Switch from HPC_STOP_M2<1:0> and programmed sequence (default) 1 = Switch from HPC_STOP_M2<1:0> directly to HPC_STOP<1:0> D5:D0 000001 www.maximintegrated.com DESCRIPTION Set to recommended value. Maxim Integrated │ 26 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 19. Address 16, Building Block SPI Enable Control (Default = 01CHEX) DATA BITS DEFAULT D9 0 TX LO I/Q Divider Enable. Enable TX LO divide-by-2 divider except for shutdown. 0 = Disable 1 = Enable D8 0 TX Mixer SPI Enable. Enable TX Mixer in all modes except shutdown. 0 = Disable 1 = Enable 0 PA Bias DAC TX Mode Enable. Enable PA Bias DAC only in TX mode. Turn-on delay is controlled by Address 27 D9:D6. 0 = Disable (default) 1 = Enable when pin TXENABLE = 1 D6 0 PA Bias DAC SPI Enable. Enable PA Bias DAC in all modes except for shutdown. The turn-on delay is controlled by Address 27 D9:D6. 0 = Disable (default) 1 = Enable except during shutdown mode D5 0 PA Driver SPI Enable. Enable PA Driver in all modes except shutdown. 0 = Enable by pin combination (default) 1 = Enable except shutdown mode D3 1 Synthesizer SPI Enable. Enable and disable PLL in all modes except shutdown. Independent of RXEN and TXEN pins. 0 = Disable 1 = Enable except shutdown mode (default) D2 1 LOGEN SPI Enable. Enable LOGEN in all modes except for shutdown. 0 = Enable by pin combination 1 = Enable except shutdown mode (default) D1 0 RX/TX Calibration Mode Enable. RX or TX mode is selected by pin RXEN or TXEN. 0 = Normal operation (default) 1 = Calibration mode 0 Chip Enable Bit. Logic AND with pin ENABLE to enable/disable the whole chip except crystal oscillator and CLKOUT pin buffer. 0 = Disable (default) 1 = Enable D7 D0 DESCRIPTION Table 20. Address 17, Synthesizer Fractional Divide Ratio #1 (Default = 155HEX) DATA BITS D9:D9 DEFAULT 0101010101 www.maximintegrated.com DESCRIPTION Synthesizer 20-bit Fractional Divide Ratio Bit<9:0>, combine with Address 18 D9:D0 to form the whole fractional word. Default = 0101010101 Maxim Integrated │ 27 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 21. Address 18, Synthesizer Fractional Divide Ratio #2 (Default = 155HEX) DATA BITS DEFAULT D9:D9 0101010101 DESCRIPTION Synthesizer 20-bit Fractional Divide Ratio Bit<19:10>, combine with Address 17 D<9:0> to form the whole fractional word. Default = 0101010101 Table 22. Address 19, Synthesizer Integer Divide Ratio (Default = 153HEX) DATA BITS DEFAULT D9:D8 01 D7:D0 1010011 DESCRIPTION Sets the LO Generation Band Switch Control for Optimal TX Spur. 00 = 2300~2399.99MHz 01 = 2400~2499.99MHz (default) 10 = 2500~2599.99MHz 11 = 2600~2700MHz Synthesizer 8-Bit Integer Divide Ratio. Default = 01010011 Table 23. Address 20, Synthesizer Configuration#1 (Default = 241HEX) DATA BITS DEFAULT D9:D7 100 D6 1 Synthesizer Turbo Mode Enable. 0 = Disable 1 = Enable. D5 0 CLOCKOUT Buffer Drive. 0 = 1x drive (default) 1 = 4x drive 00 Selects the Charge-Pump Current. 00 = 3.2mA diff. CP (default) 01 = 1.6mA diff. CP 10 = 1.6mA single-ended CP 11 = 0.8mA single-ended CP D2:D1 00 Sets the Reference Divider Ratio. 00 = Divide-by-1 (default) 01 = Divide-by-2 10 = Divide-by-4 11 = Divide-by-8 D0 1 Fractional-N PLL Mode Enable. 1 = Enable the fractional-N PLL 0 = Enable the integer-N PLL. D4:D3 www.maximintegrated.com DESCRIPTION Set to recommended value. Maxim Integrated │ 28 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 24. Address 21, Synthesizer Configuration#2 (Default = 02DHEX) DATA BITS DEFAULT DESCRIPTION 000 Synthesizer Test Output Select. D<9> = 1 programs charge pump into test mode. D<8:7> decide which PLL test signal is delivered to DOUT MUX and finally selected by Address 9 D<7:5>. 000 = Lock detect (default) 001 = Sigma-delta modulator TVM output 010 = Reference-divider output 011 = Main divider output 100 = CP in low-Z mode and select lock detect 101 = CP in source mode and select sigma-delta modulator 110 = CP in sink mode and select reference-divider output 111 = CP in high-Z mode and select main divider output (used for VCO frequency estimation) D6:D5 01 Charge-Pump Linearity Current Select. 00 = Disable 01 = +3% (default) 10 = +9% 11 = +12% D4:D0 01101 D9:D7 Set to recommended value. Table 25. Address 22, VCO Auto-Select (VAS) Configuration (Default = 1A9HEX) DATA BITS DEFAULT DESCRIPTION D9:D8 01 Set to recommended value. D7 1 VAS Triggering by Address 17 Enable. See Address 17 definitions for details. 0 = Disable for small frequency adjustment (i.e.~100kHz). 1 = Enable for channel switching (default) D6:D2 01010 D1 0 VAS Relock Mode Select. 0 = Relock starting at sub-band selected by Address 23 D4:D0 (default) 1 = Relock starting at present acquired sub-band. D0 1 VAS Operating Mode Select. 0 = Select VCO subband by SPI Address 23 D<4:0> (VAS_SPI<4:0>) 1 = Select VCO subband by VAS (default) Set to recommended value. Table 26. Address 23, LO Miscellaneous Configuration (Default = 24FHEX) DATA BITS DEFAULT D9 1 D8:D5 0010 Set to recommended value. 01111 VAS Sub-band SPI Overwrite. Active when Address 22 D0 (VAS_MODE) = 0. 00000 = Minimum frequency … 01111 = 15 (default) … 11111 = Maximum frequency D4:D0 www.maximintegrated.com DESCRIPTION VCO SPI Enable. Enable VCO except shutdown mode. 0 = Disable 1 = Enable Maxim Integrated │ 29 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 27. Address 24, Crystal Oscillator Configuration (Default = 180HEX) DATA BITS DEFAULT D9 0 Crystal Oscillator Core Enable. Enable except shutdown mode. 0 = Disable (default) 1 = Enable D8 1 Sets the CLKOUT Divide Ratio. 0 = Divide-by-1 1 = Divide-by-2 (default) D7 1 CLKOUT Pin Enable. 0 = Disable 1 = Enable (default) D6:D0 0000000 DESCRIPTION Crystal Oscillator Frequency Tuning. 000000 = Maximum frequency (default) … 111111 = Minimum frequency Table 28. Address 25, Voltage Controlled Oscillator (VCO) Configuration (Default = 100HEX) DATA BITS DEFAULT DESCRIPTION D9:D8 01 VCO Buffer Bias Control. 00 = 800µA 01 = 1200µA (default) 10 = 1600µA 11 = 2000µA D7:D5 000 Set to recommended value. D4:D1 0000 VCO Bias Trim SPI Code. Active when Address 25 D<0> (VCO_BIAS_SPI_EN) = 1. Trim word for VCO bias trim. 0000 = Minimum bias (default) … 1000 = Nominal process … 1111 = Maximum bias D0 0 VCO Bias Trim SPI Overwrite Enable. 0 = By trim block (default) 1 = By SPI Table 29. Address 26, LO Generation (LOGEN) Configuration (Default = 3CAHEX) DATA BITS DEFAULT D9:D0 1111001010 www.maximintegrated.com DESCRIPTION Set to recommended value. Maxim Integrated │ 30 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 30. Address 27, PA Driver and PA Bias DAC (PADRV and PADAC) Configuration (Default = 3E3HEX) DATA BITS DEFAULT D9 1 TX DC Offset Correction. 0 = Disable 1 = Enable D8 1 PA DRV/DAC On/Off Gating by VAS TXOOL and PLL LD. 0 = Independent of TXOOL and LD 1 = Relock when TXOOL = 1 or LD = 0 (default) D7 1 Set to recommended value. D6 1 PA DAC Voltage-Mode Output Select. Active when Address 27 D5 (PADAC_IV) = 0. 0 = Logic “0” output 1 = Logic “1” output (default) D5 1 PA DAC I/V Output Select. 0 = Select voltage output 1 = Select current output. D4:D3 10 Set to recommended value. 011 PA Driver Bias Control. 000 = Minimum … 011 = Default … 111 = Maximum D2:D0 DESCRIPTION Table 31. Address 28, PA Bias DAC (PADAC) Configuration (Default = 0C0HEX) DATA BITS D9:D6 D5:D0 DEFAULT 0011 000000 www.maximintegrated.com DESCRIPTION PADAC Turn-On Delay Control. 0000 = 0µs 0001 = 0µs 0010 = 0.5µs … 0011 = 1.0µs (default) … 1111 = 7.0µs PADAC Output Current Control. Active when Address 27 D5 = 1 (PADAC_IV). 000000 = 0µA (default) 000001 = 5µA … 111111 = 315µA Maxim Integrated │ 31 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 32. Address 29, TX Gain Configuration (Default = 3F0HEX) DATA BITS DEFAULT DESCRIPTION TX VGA SPI Gain Control. Active when Address 29 D0 (TXVGA_GAIN_SPI_EN) = 1 000000 = MIN attenuation … 111111 = MAX attenuation (default) D9:D4 111111 D3 0 Set to recommended value. D2 0 TX DC Offset SPI Adjust Enable. 0 = By fuse (default) 1 = By SPI D1 0 Pin TR6 SPI TX VGA Control Enable. 0 = By pin (default) 1 = By SPI Address 29 D9 D0 0 TX VGA Gain SPI Control Enable. 0 = By pin (default) 1 = By SPI Address 29 D9:D4 Table 33. Address 30, TX LO I/Q Configuration (Default = 080HEX) DATA BITS DEFAULT D9:D6 0010 D5 0 D4:D0 00000 www.maximintegrated.com DESCRIPTION Set to recommended value. TX LO I/Q Phase SPI Adjust Enable. 0 = By trim (default) 1 = By Address 30 D4:D0 TX LO I/Q Phase SPI Adjust. Active when Address 30 D5 (TXLO_IQ_SPI_EN) = 1. As trim word for fuse trim. 00000 = +4deg (Q lags I by 94degs, default) … 01111 = +0deg … 11111 = -4deg (Q lags I by 86degs) Maxim Integrated │ 32 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Table 34. Address 31, TX DC Correction Configuration (Default = 000HEX) DATA BITS DEFAULT DESCRIPTION 00000 TX DC Offset Correction for Q-Channel. Active when Address 29 D2 (TX_DCCORR_SPI_EN) = 1. As trim word for fuse trim. 00000 = 992/0µA (+/-ve offset current, default) 00001 = 960/32µA 00010 = 928/64µA … 01111 = 512/480µA … 11111 = 0/992µA D9:D5 D4:D0 TX DC Offset Correction for I-Channel. Active when Address 29 D2 (TX_DCCORR_SPI_EN) = 1.As trim word for fuse trim. 00000 = 992/0µA (+/-ve offset current, default) 00001 = 960/32µA 00010 = 928/64µA 00000 … 01111 = 512/480µA … 11111 = 0/992µA Chip Information ENABLE GNDVCO BYPASS VCCVCO DOUT CS PROCESS: SiGe BiCMOS DIN RSSI B7 RXBBQ- B6 TOP VIEW RXBBQ+ Pin Configuration Package Information 36 35 34 33 32 31 30 29 28 27 26 25 RXBBI- 37 24 CPOUT- RXBBI+ 38 23 CPOUT+ VCCRXVGA 39 22 GNDCP RXHP 40 21 VCCCP VCCRXFL 41 20 VCCDIG TXBBI- 42 19 VCCXTAL MAX2837 TXBBI+ 43 18 XTAL1 TXBBQ+ 44 17 XTAL2 TXBBQ- 45 16 CLOCKOUT VCCRXMX 46 For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE 48 TQFN-EP PACKAGE CODE T4866+2 DOCUMENT NO. 21-0141 LAND PATTERN NO. 90-0007 15 SCLK TXENABLE 47 14 PABIAS + RXENABLE 48 5 6 7 8 9 VCCRXLNA B5 RXRF+ RXRF- B4 VCCTXPAD B3 B2 10 11 12 B1 4 TXRF- 3 TXRF+ 2 GNDRXLNA 13 VCCTXMX 1 THIN QFN 6mm x 6mm www.maximintegrated.com Maxim Integrated │ 33 MAX2837 2.3GHz to 2.7GHz Wireless Broadband RF Transceiver Revision History REVISION NUMBER REVISION DATE PAGES CHANGED DESCRIPTION 0 5/07 Initial release — 1 11/08 Corrected SPI description in Programmable Registers and 4-Wire SPI-Interface section 16 2 7/15 Added new Temperature Sensor Readout Through DOUT Pin, VAS Operating Procedure, VAS Readout, and VCO Subband Selection Through SPI sections. Added Register and Bit Descriptions. 16–33 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. © 2015 Maxim Integrated Products, Inc. │ 34