NON-ISOLATED DC/DC CONVERTERS

Transcription

1 S7DB-07A Series Nonisolated Compact, low profile surface mount package Fixed frequency High efficiency means less power dissipation Excellent thermal performance Optimized for cost Remote on/off Undervoltage lockout UVLO) Over current and short circuit protection Remote sense Description The Bel S7DB-07A modules are a series of non-isolated, step down DC/DC power converters that operate from a nominal 2V source. These converters are available in a range of output voltages from to. They are packaged in a compact, low profile, surface mount DIP package for ease of layout and space savings. 7A maximum output is also provided. Standard features include remote on/off, over current and short circuit protection, UVLO and output voltage adjust. These products may be used almost anywhere low voltage silicon is employed and a 2V source is available. Typical applications include file servers, routers, line cards and other computing and communications equipment. Applications Distributed power architectures Data networking equipment Telecommunications Computers and peripherals Part Number Selection Voltage Input Voltage Max. Current Max. Power Typical Efficiency Part Number 2V 7A 5.0W 92% S7DB-07A0 2V 7A 2.W 90% S7DB-07A0 2V 7A 7.5W 88% S7DB-07A2 2V 7A 2.6W 8% S7DB-07A80 2V 7A 0.5W 82% S7DB-07A0 2V 7A 8.4W 8% S7DB-07A20 page

2 Absolute Maximum Ratings Parameter Symbol Min Typical Max Unit Continuous Input Voltage Enable Terminal Voltage Ambient Temperature Storage Temperature Vin -0. V Vouten -0.. V Tamb 0 C tor -40 C Note: Use beyond the maximum ratings may cause a reliability degradation of the DC/DC converter or may permanently damage the device. Input Specifications Parameter Module Symbol Min Typical Max Units Operating Input Voltage Vin V Input Current Iin A No Load Input Current ma Remote Off Input Current 4 ma Input Reflected Ripple Current ma rms Input Reflected Ripple Current P-P) mapk I 2 t Inrush Current Transient A 2 s Turn On Voltage Threshold 0. 4 V Turn Off Voltage Threshold 8. 2 V Note: Input capacitance two 2µF/6V, ESR = 0.08 Ω max at C.. With simulated source impedance of 0nH, 5Hz to 20MHz. page 2

3 Specifications Parameter Module Symbol Min Typical Max Units Voltage Set Point Vout V Load Regulation Line Regulation 0 Regulation Over Temperature 8 2 Total Voltage Regulation Ripple and Noise 75 p-p 2 Ripple and Noise 0 rms Current Range DC Current Limit Iout 0 7 A Ioutlim A Short Circuit Surge Ioutsurge A 2 s Turn on Ton ms Overshoot at Turn On % Capacitance Cout 0 0 µ F Note: specifications are typical at nominal input, full load at C unless otherwise stated.. Vin = 2V, Iout = full load, Ta = C MHz, 0.µF ceramic cap and 0µF aluminum cap on output. page

4 Specifications Parameter Module Symbol Min Typical Max Units Transient Response V % to % of Max Load 2 V % to % of Max Load 2 Transient Response V % to % of Max Load 65 V % to % of Max Load 65 Transient Response V % to % of Max Load 0 V % to % of Max Load 0 Transient Response V % to % of Max Load 0 0 V % to % of Max Load 0 0 Transient Response V % to % of Max Load 0 0 V % to % of Max Load 0 0 Transient Response V % to % of Max Load V % to % of Max Load 0 0 Note: specifications are typical at nominal input, full load at C unless otherwise stated.. di/dt = 0.5A/µS, Ta = C with a 220µF Tantalum cap at output. 0 page 4

5 General Specifications Parameter Module Symbol Min Typical Max Units Efficiency η % Switching Frequency Fsw khz 2 Voltage Trim Range % Remote Sense Compensation Weight 0 % 0. 8 g. Vin=2V, full load and Ta= C. 2. See graphs on pages 0-. Control Specifications Parameter Module Symbol Min Typical Max Units Remote On/Off Vouten V Signal Low Unit Off) Signal High Unit On) 0 V V. With remote on/off pin 8 open, the module is on. Note: On/off pin designed to work with an open collector/drain switch. page 5

6 Efficiency Data Module Module Efficiency 94% 92% 90% 88% 86% 84% Current 0.8v 2.0v.2V 94% 92% 90% 88% 86% 84% 82% 80% 78% Current 0.8V 2.0V.2V Module Module Efficiency 90% 85% 80% 75% Current 0.8V 2.0V.2V Efficiency 90% 88% 86% 84% 82% 80% 78% 76% 74% Current 0.8V 2.0V.2V Module Module 89% 90% Efficiency 84% 79% 0.8V 2.0V.2V Efficiency 85% 80% 0.8V 2.0V.2V 74% Current 75% Current page 6

7 Ripple and Noise 0.µF ceramic cap and 0µF aluminum electrolytic cap added at the output. Ripple and noise at full load and 2Vdc input, dc output and Ta= C Ripple and noise at full load and 2Vdc input, dc output and Ta= C Ripple and noise at full load and 2Vdc input, dc output and Ta= C Ripple and noise at full load and 2Vdc input, dc output and Ta= C Ripple and noise at full load and 2Vdc input, dc output and Ta= C Ripple and noise at full load and 2Vdc input, dc output and Ta= C page 7

8 Transient Response Transient response: di/dt = 0.5A/µS, external load capacitance Co=220µF aluminum cap at output Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C page 8

9 Transient Response Transient response: di/dt = 0.5A/µS, external load capacitance Co=4µF Tantalum capacitor) Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C Vout= % to % load transients at 2V input and Ta= C page 9

10 Thermal Considerations Derating Curve 7 LFM 6 Current A) Natural Convection Ambient Temperature, Ta C) Current vs. Local Ambient Temperature and Air Velocity Voltage Set-Point Adjustment Trim Down Test Circuit Trim Up Test Circuit Vo Vo Trim Trim Gnd Gnd page 0

11 Voltage Set-Point Adjustment S7DB-07A0 Trim Resistor Calculation Rtrim down = 0.52 Vo Vo, adj 4.55) Kohm Trim resistor value Rtrim_downKohm) Adjusted output voltage Vo,adj V) 90. Rtrim up = 2 Vo, adj Vo 2.05) Kohm Trim resistor value,rtrim_upkohm) Adjusted output voltage Vo,adjV) Trim resistor value Rtrim_downKohm) Adjusted output voltage Vo,adj V) S7DB-07A0 Trim Resistor Calculation Rtrim down = 5.08 Vo Vo, adj 4.55) Kohm Trim resistor value,rtrim_upkohm) Rtrim up =.75 Vo, adj Vo 2.05) Kohm Adjusted output voltage Vo,adjV) page

12 Voltage Set-Point Adjustment S7DB-07A2 Trim Resistor Calculation Rtrim down =.926 Vo Vo, adj 4.64) Kohm Trim resistor value Rtrim_downKohm) Adjusted output voltage Vo,adj V) Rtrim up = 4.02 Vo, adj Vo.47) Kohm Trim resistor value,rtrim_upkohm) Adjusted output voltage Vo,adjV) Trim resistor value Rtrim_downKohm) Adjusted output voltage Vo,adj V) S7DB-07A80 Trim Resistor Calculation Rtrim down =.869 Vo Vo, adj.4) Kohm Trim resistor value,rtrim_upkohm) Rtrim up =.072 Vo, adj Vo 7.5) Kohm Adjusted output voltage Vo,adjV) page 2

13 Voltage Set-Point Adjustment S7DB-07A0 Trim Resistor Calculation Rtrim down = 2.4 Vo Vo, adj.4) Kohm Trim resistor value Rtrim_downKohm) Adjusted output voltage Vo,adj V) Rtrim up =.072 Vo, adj Vo 7.5) Kohm Trim resistor value,rtrim_upkohm) Adjusted output voltage Vo,adjV) Trim resistor value Rtrim_downKohm) Trim resistor value,rtrim_upkohm) Adjusted output voltage Vo,adj V) Adjusted output voltage Vo,adjV) S7DB-07A20 Trim Resistor Calculation Rtrim down = Rtrim up = Vo Vo, adj.728 Vo, adj Vo 6.58) Kohm 4.42) Kohm page

14 Mechanical.22 [0.99] 0.94 [0.0] Suggested PCB Pad Layout 0.97 [5.00] 0.67 [7.00] [22.7] 0.20 [.05] 0. [2.54] 0-5 6X 0.02 [2.59] [.02] 5X 0.97 [5.00] 0. [8.76] 0.00 [0.] [2.0] [0.0] 2X 0.0 [.27] 2X [.99] Pin Function Dimensions are in inches [millimeters]. Standard dimension tolerance is ±0.005 [0.] unless otherwise noted. Ground 2 Ground Ground Ground 5 +Vin 6 +Vin 7 Trim 8 Remote On/Off Remote Sense +) 0 +Vo +Vo 2 +Vo CORPORATE Bel Fuse Inc. 206 Van Vorst Street Jersey City, NJ 02 Tel Fax page 4 FAR EAST Bel Fuse Ltd. 8F / 8 Luk Hop Street San Po Kong Kowloon, Hong Kong Tel Fax EUROPE Bel Fuse Europe Ltd. Preston Technology Management Centre Marsh Lane, Suite G7, Preston Lancashire, PR 8UD, U.K. Tel Fax