Home / 最新消息
MAXIM New Products -MAX77271 & MAX14975
2013-05-13
MAX77271
Multimode PA Step-Down Converter with Linear Bypass Mode
Longer Battery Life and Lower Temperature Operation - PA Power Supply for the Latest Multimode/Carrier Smartphones
Description
The MAX77271 step-down converter is optimized for powering the power amplifier (PA) in multistandard handsets such as LTE, WCDMA, TD-SCDMA, GSM, and EDGE. The device integrates a high-efficiency PWM stepdown converter for medium- and low-power transmission with an 85mΩ (typ) low dropout (LDO) bypass regulator, in parallel with the step-down converter, enabling high-power transmission.
The IC uses an analog input driven by an external DAC to control the output voltage linearly for continuous PA power adjustment. The bypass LDO powers the PA directly from the battery during high-power transmission or in case of insufficient headroom between the input and programmed output. The bypass LDO is enabled when the output voltage is greater than 0.65V. In the case where the output current exceeds the step-down converter current limit, the bypass LDO provides supplementary current to the output, ensuring a stable output voltage. The bypass LDO also provides a smooth transition between step-down regulation and operation in dropout.
The IC is available in a 9-bump, 1.6mm x 1.6mm WLP package (0.69mm max height).
The IC uses an analog input driven by an external DAC to control the output voltage linearly for continuous PA power adjustment. The bypass LDO powers the PA directly from the battery during high-power transmission or in case of insufficient headroom between the input and programmed output. The bypass LDO is enabled when the output voltage is greater than 0.65V. In the case where the output current exceeds the step-down converter current limit, the bypass LDO provides supplementary current to the output, ensuring a stable output voltage. The bypass LDO also provides a smooth transition between step-down regulation and operation in dropout.
The IC is available in a 9-bump, 1.6mm x 1.6mm WLP package (0.69mm max height).
Key Features
-
PA Step-Down Converter
- 7µs (typ) Settling Time for 0.7V to 3.4V Output Voltage Change
- Dynamic Output Voltage Setting from 0.5V to VIN
- 85mΩ PFET and 100% Duty Cycle for Low Dropout
- 3MHz Switching Frequency
- Low Output Voltage Ripple
- 2% Output Voltage Accuracy Over Load, Line, and Temperature
- Tiny External Components
- 2.5A Output Current Capability
- Simple Logic On/Off Control
- Low 0.1µA Shutdown Current
- 2.7V to 5.5V Supply Voltage Range
- Thermal Overload Protection
- 1.6mm x 1.6mm WLP Package (0.69mm max Height)
- Slot-to-Slot Average Power Tracking for LTE, TD-SCDMA, and WCDMA Standards
MAX14975
Robust Dual USB 3.0 Equalizer/Redriver with Extended Temperature Operation
Save Power While Supporting SuperSpeed USB 3.0 Interface in a Ruggedized Design
Description
The MAX14975 dual SuperSpeed USB 3.0 equalizer/redriver utilizes programmable input equalization and output deemphasis to reduce deterministic jitter and restore signal loss caused by circuit-board or signal-cable losses, and allows optimal placement of key SuperSpeed USB 3.0 components and longer circuit-board traces or cables. The device features advanced power management with receiver detection and explicit support for USB 3.0 low-frequency periodic signals (LFPS).
The device is available in a small, 24-pin (4.0mm x 4.0mm) TQFN package with flow-through traces for optimal layout and minimal space requirements. The device is specified over the -40°C to +85°C extended operating temperature range.
The device is available in a small, 24-pin (4.0mm x 4.0mm) TQFN package with flow-through traces for optimal layout and minimal space requirements. The device is specified over the -40°C to +85°C extended operating temperature range.
Key Features
-
Advanced Power-Saving Sleep Modes
- Standby State: < 1mW (typ)
- Receiver Detect State: 23mW (typ)
- Dynamic Power-Down State: 82.5mW (typ)
- Active State: 304mW (typ)
-
High-Performance Solution Designed to Overcome Lossy Channels
- Three Levels of Input Equalization Up to 10dB
- Six Levels of Output Deemphasis Up to 4dB
- Compensates Up to 30in of Channel Losses with Deterministic Jitter: 12psP-P (max); Random Jitter: 1psRMS (max)
- 10dB (typ) of Return Loss Up to 2.5GHz
-
Designed to Reliably Operate in Harsh Environments
- Industrial Temperature Rated: -40°C to + 85°C
- ±8kV Human Body Model (HBM) ESD Protection on All Pins
- Housed in a Flow-Through (4.0mm x 4.0mm, 24-Pin) TQFN Package for Resistance to Vibration/Shocks
