MAX8805W MAXIM [Maxim Integrated Products], MAX8805W Datasheet

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... PA power adjustment. The REFIN to OUT gain is available in two options (2V/V for the MAX8805Y/MAX8805Z and 2.5V/V for the MAX8805W/MAX8805X). At high-duty cycle, the MAX8805W/MAX8805X/MAX8805Y/MAX8805Z auto- matically switch to the bypass mode, connecting the input to the output through a low-impedance (60mΩ ...

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... ELECTRICAL CHARACTERISTICS ( IN1A IN1B IN2 PA_EN (MAX8805W/MAX8805X -40°C to +85°C. Typical values are PARAMETER INPUT SUPPLY Input Voltage V IN1A Input Undervoltage Threshold V IN1A Shutdown Supply Current ...

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... PWM Step-Down Converters in 2mm x 2mm WLP for WCDMA PA Power ELECTRICAL CHARACTERISTICS (continued IN1A IN1B IN2 PA_EN (MAX8805W/MAX8805X -40°C to +85°C. Typical values are PARAMETER REFIN V REFIN Dual Mode™ Threshold LX p-channel MOSFET switch, I On-Resistance n-channel MOSFET rectifier, I ...

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... PWM Step-Down Converters in 2mm x 2mm WLP for WCDMA PA Power ELECTRICAL CHARACTERISTICS (continued IN1A IN1B IN2 PA_EN (MAX8805W/MAX8805X -40°C to +85°C. Typical values are PARAMETER Output Noise 100Hz to 100kHz < I Output Capacitor for Stable Operation 0 < I Shutdown Output Impedance V ...

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... 3.2V IN1 V = 4.2V IN1 V = 3.6V IN1 100 200 300 400 500 600 700 LOAD CURRENT (mA) PA STEP-DOWN CONVERTER EFFICIENCY vs. LOAD CURRENT (MAX8805W/MAX8805Y) 100 4.2V IN1 V = 3.2V IN1 3.6V IN1 100 200 300 400 500 600 700 LOAD CURRENT (mA) ...

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... IN1 -20 -40 -60 -80 -100 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 REFIN VOLTAGE (V) 6 _______________________________________________________________________________________ Typical Operating Characteristics (continued) = 2.85V 2.85V 7.5Ω, circuit of Figure 5, T LDO1 LDO2 PA PA STEP-DOWN CONVERTER EFFICIENCY vs. LOAD CURRENT (MAX8805W/MAX8805Y) 100 4. 400 500 600 700 0 4.0 3.5 MAX8805X/MAX8805Z 3.0 2.5 2.0 1.5 1.0 0.5 400 500 600 700 0 REFIN vs ...

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... V = 1.2V 50mA PA PA SWITCHING WAVEFORMS (MAX8805W/MAX8805Y) MAX8805W/X/Y/Z toc20 V 20mV/div AC-COUPLED 500mA/div 2V/div V = 1.2V 500mA +25°C, unless other- A REFIN vs. REFIN TO OUT GAIN (MAX8805W 3.2V, NO LOAD IN1 4.2V, NO LOAD IN1 10 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 REFIN VOLTAGE (V) PA STEP-DOWN CONVERTER LIGHT-LOAD MAX8805W/X/Y/Z toc19 V PA 20mV/div I ...

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... V = 2.85V 7.5Ω, circuit of Figure 5, T LDO1 LDO2 PA WAVEFORMS (MAX8805W/MAX8805Y) MAX8805W/X/Y/Z toc22 V PA_EN 2V/div 1V/div 500mA/div LX PA STEP-DOWN CONVERTER LINE TRANSIENT RESPONSE (MAX8805W/MAX8805Y) MAX8805W/X/Y/Z toc24 4.0V 4.0V V 500mV/div IN1 V PA 50mV/div AC-COUPLED I 200mA/div LX PA STEP-DOWN CONVERTER LOAD TRANSIENT RESPONSE (MAX8805W/MAX8805Y) MAX8805W/X/Y/Z toc26 I ...

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... BYPASS-FET TRANSIENT RESPONSE MAX8805W/X/Y/Z toc32 V REFIN 2V SINUSOIDAL V SIGNAL 1V/div REFIN 0.6V 2V/div 1. 500mA/div +25°C, unless other- A (MAX8805Y/MAX8805Z) MAX8805W/X/Y/Z toc29 1.5V 2V/div 0V 3.6V 2V/div 1.2V 500mA/div 20μs/div (MAX8805W/MAX8805X) MAX8805W/X/Y/Z toc31 2V 2V/div 0V 3.6V 2V/div 1.2V 500mA/div 20μs/div (MAX8805Y/MAX8805Z) MAX8805W/X/Y/Z toc33 IS A 0.4V TO 1V/div 3.6V 1V/div 500mA/div 200μs/div 9 ...

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... 100mA/div 150 120 4.5 5.0 5.5 = +25°C, unless other STEP-DOWN CONVERTER AUTOMATIC BYPASS-FET TRANSIENT RESPONSE (MAX8805W/MAX8805X) MAX8805W/X/Y/Z toc35 1V/div 3.6V 1V/div 0.48V TO REFIN 2.1V SINSOIDAL SIGNAL 500mA/div 200μs/div PA STEP-DOWN CONVERTER SHUTDOWN RESPONSE (MAX8805X/MAX8805Z) MAX8805W/X/Y/Z toc37 2V 2V/div 0V 1.2V 2V/div 100mA/div 10μ ...

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... LDO1 100mA/div 0mA V LDO2 50mV/div + 200mV LDO1,2 = +25°C, unless other- A vs. FREQUENCY 0 100 1000 FREQUENCY (kHz) LDO LINE TRANSIENT RESPONSE MAX8805W/X/Y/Z toc43 4.0V 4.0V 500mV/div 3.5V 5mV/div I = 80mA LDO_ 20μs/div LDO1, LDO2 TURN ON AND SHUTDOWN RESPONSE MAX8805W/X/Y/Z toc45 2V/div 2V/div 2V/div 1ms/div 11 ...

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... PA_ is connected to the internal feedback network. Bypass PA_ with a 2.2µF ceramic capacitor as close as possible to PA_ and PGND. 12 ______________________________________________________________________________________ FUNCTION for the MAX8805W/MAX8805X. When V REFIN for the MAX8805W/MAX8805X, bypass mode is enabled. IN2 Pin Description for the REFIN reaches 0.465 x V REFIN ...

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PWM Step-Down Converters in 2mm x 2mm WLP for WCDMA PA Power IN1A IN1B REFIN IN2 REFBP 1.25V REFERENCE AGND BANDGAP EN1 CONTROL EN2 LOGIC PA_EN Figure 1. Block Diagram ______________________________________________________________________________________ BYPASS ...

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... REFIN voltage, the load regulation should be considered. Because inductor resistance is typically well specified and the typical resistive load, the MAX8805Y/MAX8805Z REFIN less than 2V/V, and the MAX8805W/MAX8805X gain is slightly less than 2.5V/V. OUT 14 ______________________________________________________________________________________ During high-power transmission, the bypass mode con- nects IN1A and IN1B directly to PAA and PAB with the internal 60mΩ ...

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... MAX8805X/MAX8805Z allow the use of physically smaller inductors at the cost of slightly lower efficiency. The lower switching frequency of the MAX8805W/MAX8805Y results in greater efficien the cost of a physically larger inductor. See the Output Voltages Typical Operating Characteristics for efficiency graphs for both the MAX8805W/MAX8805Y and MAX8805X/ MAX8805Z ...

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PWM Step-Down Converters in 2mm x 2mm WLP for WCDMA PA Power Table 2. Suggested Inductors MANUFACTURER SERIES Coilcraft LPO3310 MIPF2520 FDK MIPS2520 MIPF2016 Hitachi KSLI-252010 Murata LQH32C_53 Sumida CDRH2D09 CDRH2D11 Taiyo Yuden CB2518T D3010FB D2812C TOKO D310F D312C ...

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... With X7R or X5R dielectrics, a capacitance equal to the sum is sufficient at all operating temperatures. Thermal Considerations In most applications, the MAX8805W/MAX8805X/ MAX8805Y/MAX8805Z do not dissipate much heat due to their high efficiency. However, in applications where the MAX8805W/MAX8805X/MAX8805Y/MAX8805Z run at high ambient temperature with heavy loads, the heat dissipated may exceed the maximum junction tempera- ture of the IC ...

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PWM Step-Down Converters in 2mm x 2mm WLP for WCDMA PA Power AGND C BYP C LDO2 C IN2 VIN Figure 3. Recommended PCB Layout 18 ______________________________________________________________________________________ PGND VPA C LDO1 5.5mm C C IN1 ...

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... Li+ BATTERY 2.2μF DAC BASEBAND PROCESSOR GPIO GPIO GPIO GPIO 1μF *1μH FDK MIPS 2520D1R0 2.2μH FDK MIPF 2520D2R2 Figure 4. Typical Application Circuit Using LDOs for PA Enable/Bias ______________________________________________________________________________________ MAX8805W MAX8805X MAX8805Y MAX8805Z IN1A IN1B REFIN 2MHz OR 4MHz BUCK PA_EN HP EN1 CONTROL EN2 ...

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... DAC BASEBAND PROCESSOR GPIO GPIO GPIO GPIO 2.2μF *1μH FDK MIPS 2520D1R0 2.2μH FDK MIPF 2520D2R2 Figure 5. Typical Application Circuit Using LDOs for RF Power 20 ______________________________________________________________________________________ MAX8805W MAX8805X MAX8805Y MAX8805Z IN1A IN1B REFIN 2MHz OR 4MHz BUCK PA_EN HP EN1 CONTROL EN2 IN2 ...

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PWM Step-Down Converters in 2mm x 2mm WLP for WCDMA PA Power Pin Configuration TOP VIEW REFBP AGND REFIN LDO2 PA_EN EN2 IN2 HP IN1B LDO1 EN1 PAB D1 D2 ...

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PWM Step-Down Converters in 2mm x 2mm WLP for WCDMA PA Power (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) Revision History Pages changed ...