Datasheet ADP2323 (Analog Devices)

Dual 3 A, 20 V Synchronous Step-Down Regulator with Integrated High-Side MOSFET Data Sheet ADP2323 FEATURES TYPICAL APPLICATION CIRCUIT Input voltage: 4.5 V to 20 V RTOP1 ±1% output accuracy CC1 V Integrated 90 mΩ typical high-side MOSFET IN RBOT1 C Flexible output configuration RC1 SS1 CIN1 Dual output: 3 A/3 A 1 1 B1 N1 N T F MP1 SS1 E Parallel single output: 6 A BS C O BST1 PVI INTVCC C L1 VOUT1 Programmable switching frequency: 250 kHz to 1.2 MHz CINT MODE SW1 External synchronization input with programmable phase SCFG TRK2 M1 shift, or internal clock output C TRK1 OUT1 DL1 Selectable PWM or PFM mode operation VDRV C ADP2323 DRV Adjustable current limit for small inductor GND PGND External compensation and soft start PGOOD2 PGOOD1 DL2 Startup into precharged output C M2 OUT2 SYNC Supported by ADIsimPower™ design tool RT SW2 2 2 V APPLICATIONS ROSC MP2 N L2 OUT2 T O C B2 N2 BST2 F C SS2 E PVI BS Communications infrastructure RC2 Networking and servers V C IN SS2 RBOT2 CC2 Industrial and instrumentation R C TOP2 IN2
001
Healthcare and medical
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Intermediate power rail conversion
Figure 1.
DC-to-dc point of load applications GENERAL DESCRIPTION
inputs and power good outputs provide reliable power sequencing. The ADP2323 is a full featured, dual output, step-down dc-to- To enhance system reliability, the device also includes undervoltage dc regulator based on current-mode architecture. The ADP2323 lockout (UVLO), overvoltage protection (OVP), overcurrent pro- integrates two high-side power MOSFETs and two low-side drivers tection (OCP), and thermal shutdown (TSD). for the external N-channel MOSFETs. The two pulse-width mod- The ADP2323 operates over the −40°C to +125°C junction ulation (PWM) channels can be configured to deliver dual 3 A temperature range and is available in a 32-lead LFCSP_WQ outputs or a parallel-to-single 6 A output. The regulator operates package. from input voltages of 4.5 V to 20 V, and the output voltage can
100
be as low as 0.6 V.
95
The switching frequency can be programmed between 250 kHz
90
and 1.2 MHz, or synchronized to an external clock to minimize
85
interference in multirail applications. The dual PWM channels
%) ( 80
run 180° out of phase, thereby reducing input current ripple as
Y C N
well as reducing the size of the input capacitor.
75 IE 70
The bidirectional synchronization pin can be programmed at
FFIC E
a 60°, 90°, or 120° phase shift, providing the possibility for a
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stackable multiphase power solution.
60 VOUT = 5V VOUT = 3.3V
The ADP2323 can be set to operate in pulse-frequency modulation
55
(PFM) mode at a light load for higher efficiency or in forced
50 0 0.5 1.0 1.5 2.0 2.5 3.0
002 PWM for noise sensitive applications. External compensation
OUTPUT CURRENT (A)
09357- and soft start provide design flexibility. Independent enable Figure 2. Efficiency vs. Output Current at VIN = 12 V, fSW = 600 kHz
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Document Outline Features Applications Typical Application Circuit General Description Revision History Functional Block Diagram Specifications Absolute Maximum Ratings Thermal Resistance Boundary Condition ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Theory of Operation Control Scheme PWM Mode PFM Mode Precision Enable/Shutdown Separate Input Voltages Internal Regulator (INTVCC) Bootstrap Circuitry Low-Side Driver Oscillator Synchronization Soft Start Peak Current-Limit and Short-Circuit Protection Voltage Tracking Parallel Operation Power Good Overvoltage Protection Undervoltage Lockout Thermal Shutdown Applications Information ADIsimPower Design Tool Input Capacitor Selection Output Voltage Setting Voltage Conversion Limitations Current-Limit Setting Inductor Selection Output Capacitor Selection Low-Side Power Device Selection Programming UVLO Input Compensation Components Design Design Example Output Voltage Setting Current-Limit Setting Frequency Setting Inductor Selection Output Capacitor Selection Low-Side MOSFET Selection Compensation Components Soft Start Time Programming Input Capacitor Selection External Components Recommendation Typical Application Circuits Outline Dimensions Ordering Guide