Dat a Sh eet AS1351 Programmable Dual LDO 1 General Description 2 Key Features 2 Independent Voltage Regulators with Shutdown The AS1351 is a high-performance dual CMOS low- dropout voltage regulator in a single 3x3mm package. Output Current: 200mA each LDO The efficient set of programmable power supplies is opti- One Time Programmable Output Voltage mized to deliver the best compromise between quies- (User- or Factory-Trimmed) cent current and regulator performance for mobile Programmable Output Voltage Range: 1.8 to 3.3V in phones, PDAs, MP3 players, and other battery powered 0.1V Steps devices. Accuracy: 1.5% The one-time-programmable (OTP) function provides PSRR: 70dB at 1kHz, 40dB at 100kHz greater design flexibility by allowing for independent pro- Line Regulation: 2mV gramming of the output voltage for each regulator on- site. The OTP function allows for fast prototyping reduc- Load Regulation: 0.6mV ing development times and costs significant. Factory Supply Range: 3 to 5.5V trimmed versions for full-production are also available. 0.2V Dropout Voltage I = 200mA Stability is guaranteed with ceramic output capacitors of Shutdown Current: 1A only 1F (20% X5R) up to 4.7F (20% X5R). The Supply Current Without Load: 125A (typ) low equivalent series resistance (ESR) of these capaci- tors ensures low output impedance at high frequencies. Softstart for Low Inrush Current Stable with low ESR Ceramic Capacitors from 1 to Regulation performance is excellent even under low 4.7F dropout conditions, when the power transistor has to operate in linear mode. Low Noise: 40V rms 10Hz to 100kHz Bandwidth The low-noise performance allows direct connection of Thermal Protection noise sensitive circuits without additional filtering net- Over-Current Protection works. Temperature Range: -40 to +85C The AS1351 is available in a 12-pin QFN 3x3mm pack- 12-pin QFN 3x3mm Package age. 3 Applications The AS1351 is ideal for cordless and mobile phones, MP3 players, CD and DVD players, PDAs, handheld computers, digital cameras, and any other hand-held battery-powered device. Figure 1. Pinout Assignments (Top View) N/C N/C REF 12 11 10 1 VDD EN2 9 EN1 AS1351 N/C 2 8 GND 3 7 VDD 4 5 6 13 GND (Exposed Pad) GND VOUT1 VOUT2 www.austriamicrosystems.com Revision 1.21 1 - 10AS1351 Data Sheet - Pinout 4 Pinout Pin Descriptions Figure 2. Pin Assignments (Top View Not To Scale) N/C N/C REF 12 11 10 VDD EN2 1 9 EN1 N/C 2 AS1351 8 GND 3 7 VDD 4 5 6 13 GND (Exposed Pad) GND VOUT1 VOUT2 Table 1. Pin Descriptions Number Name Description 1 EN2 Digital input to enable VOUT2. 2 EN1 Digital input to enable VOUT1. 3GND Negative supply voltage. 4GND Negative supply voltage. 5VOUT1 Regulated analog output voltage 1. 6VOUT2 Regulated analog output voltage 2. 7VDD Positive supply voltage. Pins 7 and 9 must be connected together externally. 8 N/C Not connected. 9VDD Positive supply voltage. Pins 7 and 9 must be connected together externally. 10 REF Analog reference voltage connect to 100nF capacitor during normal operation. 11 N/C Not connected. 12 N/C Not connected. 13 GND Negative supply voltage this pin is the exposed pad. All GND pins (3, 4, and 13) must be connected together externally. www.austriamicrosystems.com Revision 1.21 2 - 10