Datasheet LTC7851, LTC7851-1 (Analog Devices) - 4
| Manufacturer | Analog Devices |
| Description | Quad Output, Multiphase Step-Down Voltage Mode DC/DC Controller with Accurate Current Sharing |
| Pages / Page | 38 / 4 — ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply … |
| Revision | A |
| File Format / Size | PDF / 4.2 Mb |
| Document Language | English |
ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply over the specified operating
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Text Version of Document
LTC7851/LTC7851-1
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2). VCC = 5V, VRUN1,2,3,4 = 5V, VFREQ = VCLKIN = 0V, VFB = 0.6V, fOSC = 600kHz, unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Current Sense Amplifier
VISENSE(MAX) Maximum Differential Current Sense Voltage LTC7851 50 mV (VISNSP – VISNSN) LTC7851-1 150 mV AV(ISENSE) Voltage Gain LTC7851 20 V/V LTC7851-1 4 V/V VCM(ISENSE) Input Common Mode Range –0.3 VCC – 0.5 V IISENSE SENSE Pin Input Current VCM = 1.5V 100 nA VIAVG Zero Current IAVG Pin Voltage VISNSP = VISNSN 500 mV VOS Current Sense Input Referred Offset LTC7851 l –1 1 mV LTC7851-1 l –3 3 mV
Oscillator and Phase-Locked Loop
fOSC Oscillator Frequency VCLKIN = 0V VFREQ = 0V l 520 600 680 kHz VFREQ = 5V l 0.85 1 1.15 MHz VCLKIN = 5V RFREQ < 24.9k 180 kHz RFREQ = 30.9k 370 kHz RFREQ = 36.5k 570 kHz RFREQ = 48.7k 970 kHz RFREQ = 64.9k 1.4 MHz RFREQ = 82.5k 1.9 MHz RFREQ = 88.7k 2.1 MHz Maximum Frequency 3 MHz Minimum Frequency 0.25 MHz IFREQ FREQ Pin Output Current VFREQ = 0.8V 18.5 20 21.5 µA tCLKIN(HI) CLKIN Pulse Width High VCLKIN = 0V to 5V 100 ns tCLKIN(LO) CLKIN Pulse Width Low VCLKIN = 0V to 5V 100 ns RCLKIN CLKIN Pull Up Resistance 20 kΩ VCLKIN CLKIN Input Threshold VCLKIN Falling 0.8 V VCLKIN Rising 2 V VFREQ FREQ Input Threshold VCLKIN = 0V VFREQ Falling 1.5 V VFREQ Rising 2.5 V VOL(CLKOUT) CLKOUT Low Output Voltage ILOAD = –500µA 0.2 V VOH(CLKOUT) CLKOUT High Output Voltage ILOAD = 500µA VCC – 0.2 V θ2 – θ1 Channel 2 to Channel 1 Phase Relationship 180 Deg θ3 – θ1 Channel 3 to Channel 1 Phase Relationship 90 Deg θ4 – θ1 Channel 4 to Channel 1 Phase Relationship 270 Deg θCLKOUT – θ1 CLKOUT to Channel 1 Phase Relationship 45 Deg
PWM Output
PWM PWM Output High Voltage ILOAD = 500µA l VCC – 0.5 V PWM Output Low Voltage ILOAD = –500µA l 0.5 V PWM Output Current in Hi-Z State ±5 µA PWM Maximum Duty Cycle 91.5 % Rev A 4 For more information www.analog.com Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2). VCC = 5V, VRUN1,2,3,4 = 5V, VFREQ = VCLKIN = 0V, VFB = 0.6V, fOSC = 600kHz, unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Current Sense Amplifier
VISENSE(MAX) Maximum Differential Current Sense Voltage LTC7851 50 mV (VISNSP – VISNSN) LTC7851-1 150 mV AV(ISENSE) Voltage Gain LTC7851 20 V/V LTC7851-1 4 V/V VCM(ISENSE) Input Common Mode Range –0.3 VCC – 0.5 V IISENSE SENSE Pin Input Current VCM = 1.5V 100 nA VIAVG Zero Current IAVG Pin Voltage VISNSP = VISNSN 500 mV VOS Current Sense Input Referred Offset LTC7851 l –1 1 mV LTC7851-1 l –3 3 mV
Oscillator and Phase-Locked Loop
fOSC Oscillator Frequency VCLKIN = 0V VFREQ = 0V l 520 600 680 kHz VFREQ = 5V l 0.85 1 1.15 MHz VCLKIN = 5V RFREQ < 24.9k 180 kHz RFREQ = 30.9k 370 kHz RFREQ = 36.5k 570 kHz RFREQ = 48.7k 970 kHz RFREQ = 64.9k 1.4 MHz RFREQ = 82.5k 1.9 MHz RFREQ = 88.7k 2.1 MHz Maximum Frequency 3 MHz Minimum Frequency 0.25 MHz IFREQ FREQ Pin Output Current VFREQ = 0.8V 18.5 20 21.5 µA tCLKIN(HI) CLKIN Pulse Width High VCLKIN = 0V to 5V 100 ns tCLKIN(LO) CLKIN Pulse Width Low VCLKIN = 0V to 5V 100 ns RCLKIN CLKIN Pull Up Resistance 20 kΩ VCLKIN CLKIN Input Threshold VCLKIN Falling 0.8 V VCLKIN Rising 2 V VFREQ FREQ Input Threshold VCLKIN = 0V VFREQ Falling 1.5 V VFREQ Rising 2.5 V VOL(CLKOUT) CLKOUT Low Output Voltage ILOAD = –500µA 0.2 V VOH(CLKOUT) CLKOUT High Output Voltage ILOAD = 500µA VCC – 0.2 V θ2 – θ1 Channel 2 to Channel 1 Phase Relationship 180 Deg θ3 – θ1 Channel 3 to Channel 1 Phase Relationship 90 Deg θ4 – θ1 Channel 4 to Channel 1 Phase Relationship 270 Deg θCLKOUT – θ1 CLKOUT to Channel 1 Phase Relationship 45 Deg
PWM Output
PWM PWM Output High Voltage ILOAD = 500µA l VCC – 0.5 V PWM Output Low Voltage ILOAD = –500µA l 0.5 V PWM Output Current in Hi-Z State ±5 µA PWM Maximum Duty Cycle 91.5 % Rev A 4 For more information www.analog.com Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts
