HV816K6-G

HV816K6-G SUTEX | Alldatasheet

Document overview

• Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
• PDF pages: 5

Technical content

Features

Supply voltage 8.0 to 450V Voltage output device Typical gain 5.0±1% Max VSENSE 500mV Fast rise and fall times, 700ns to 2.0µs Maximum quiescent current 50µA

Applications

The HV7801 high side current monitor IC transfers a high- side current measurement voltage to its ground referenced output with a voltage gain of five. The measurement voltage typically originates at a current sense resistor which is located in a “high side” circuit, such as the positive supply line. This monitor IC features a very wide input voltage range, high accuracy of transfer ratio, small size, low component count, low power consumption, ease of use, and low cost. Offline applications, battery, and portable applications can be served equally well due to the wide input voltage range and the low quiescent current. Typical Application Circuit High Side Current Monitor 8.0 to 450V, Gain of 5 VOU T = 5 • VSENS E 8V to 450V Input ISENSEVSENSE V VOUT HV7801 IN LOAD GND OUT

• 1235 Bordeaux Drive, Sunnyvale, CA 94089 ● Tel: 408-222-8888 ● www.supertex.com

Ordering Information

-G indicates package is RoHS compliant (‘Green’) Absolute Maximum Ratings Parameter Value VIN, VLOAD -0.5V to +450V VOUT -0.5V to +10V VSENSE -0.5V to +5.0V ILOAD ±10mA Operating ambient temperature -40°C to +85°C Operating junction temperature -40°C to +125°C Storage temperature -65°C to +150°C Absolute maximum ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is not implied. Continuous operation of the device at the absolute rating level may affect device reliability. All voltages are referenced to device ground. Thermal Resistance Sym Parameter Min Typ Max Units Conditions Supply VIN Supply voltage 8.0 - 450 V * --- IQ Quiescent supply current - - 50 µA - VIN = 8V to 450V, VSENSE = 0mV Input and Output ROUT OUT pin output resistance - 16.5 - kΩ - --- VOUT Output voltage 0 - 65 mV - VSENSE = 0mV 420 - 580 VSENSE = 100mV 913 - 1087 VSENSE = 200mV 2395 - 2605 VSENSE = 500mV Dynamic Characteristics tRISE Output rise time, 10% to 90% - 0.7 - µs - VSENSE step 5.0mV to 500mV - - 2.0 VSENSE step 0mV to 500mV tFALL Output fall time, 90% to 10% - 0.7 2.0 µs - VSENSE step 500mV to 0mV Electrical Characteristics (TA = 25°C unless otherwise specified, VIN = 8.0 to 450V) * Values apply over the full temperature range. INLOAD OUT GND 5-Lead SOT-23 (top view) 5 4 2 3 NC Pin Configuration Package θja 5-Lead SOT-23 191 OC/W Note: Thermal testboard per JEDEC JESD51-7 Product Marking Y = Last Digit of Year Sealed W = Code for Week Sealed = “Green” Packagin g 7BYW 5-Lead SOT-23

• 1235 Bordeaux Drive, Sunnyvale, CA 94089 ● Tel: 408-222-8888 ● www.supertex.com Block Diagram

Application Information

The HV7801 high side current monitor IC features accurate current sensing, small size, low component count, low power consumption, exceptional input voltage range, ease of use and low cost. Typical use is measurement of line or load current for purpose of overcurrent protection, metering and current regulation. High side current sensing, as opposed to ground referenced or low side current sensing, is desirable or required when: The current to be measured does not flow in a circuit associated with ground. The measurement at ground level can lead to ambiguity due to changes in the grounding arrangement during field use. Introduction of a sense resistor in the system ground is undesirable due to issues with safety, EMI, or signal degradation due to common impedance coupling. Principle of Operation The operational amplifier and MOSFET forces the voltage across R A to track VSENSE within the limit of the offset voltage of the opamp, i.e. VRA = VSENSE. The current through R A returns to ground through R B. RA and R B are integrated, exhibiting tight matching and excellent tracking. By design, RB is five times larger than RA. Consequently, VRB is five times larger than VRA, thus resulting in a voltage gain of 5. OUT Pin Loading Effects Note that the OUT pin has an typical output resistance of 16.5kΩ. Loading the output causes the voltage gain to drop and rise/fall times to increase. For example, assuming output resistance is 16.5kΩ, the load resistance should exceed 16.5MΩ in order to limit the drop in gain to 1 part in 1000. Again assuming output resistance is 16.5kΩ, capacitive loading of 6pF results in a response pole with a time constant of 100ns, not high enough to materially affect the output rise and fall times (about 700ns). ISENSEVSENSE RSENSE Bias Circuits HV7801 IN LOAD GND OUT VOUT RA RB RP (Optional, see text)

• 1235 Bordeaux Drive, Sunnyvale, CA 94089 ● Tel: 408-222-8888 ● www.supertex.com Sense Resistor Considerations Limit the sense resistor voltage to 500mV during normal operating conditions. Limit the power dissipation in the sense resistor to suit the application; a high sense voltage benefits accuracy, but increases power dissipation. Consider the use of Kelvin connections for applications where considerable voltage drops may occur in the PCB traces. A layout pattern which minimizes voltage across the sense lines is shown below. Choose a low inductance type sense resistor if preservation of bandwidth is important. The use of Kelvin connections helps by excluding the inductive voltage drop across the traces leading to the sense resistor. The inductive voltage drop may be substantial when operating at high frequencies. A trace or component inductance of just 10nH contributes an impedance of 6.2m Ω at 100kHz, which constitutes a 6% error when using a 100mΩ sense resistor. Transient Protection Add a protection resistor (R P) in series with the LOAD pin if VSENSE can exceed 5V in a positive sense or 600mV in a negative sense, whether in a steady state or in transient conditions. A large VSENSE may occur during system startup or shutdown due to the charging and discharging of bulk storage capacitors. VSENSE may be large due to fault conditions, such as a short circuit condition, or a broken or missing sense resistor. An internal 5V Zener diode with a current rating of 10mA protects the sense amplifier inputs. The block diagram shows the orientation of this diode. The Zener diode provides clamping at 5V for a positive V SENSE and at 600mV for a negative VSENSE. Under worst case conditions, limit the Zener current to 10mA. A 100kΩ resistor limits the maximum Zener diode current to 4.5mA when V SENSE is 450V, whether positive or negative. Note that the protection resistor may affect the bandwidth. The resistor forms an RC network with the trace and pin capacitance at the LOAD pin. A capacitance of 5pF results in a time constant of 500ns. The protection resistor may cause an offset voltage due to bias current at the LOAD input. Under worst case bias current (1nA), a 100kΩ protection resistor could cause an offset of 100µV or 0.2% of full scale. Note that the bias current is nominally zero as the LOAD is a high impedance CMOS input. Pin Description Pin # Pin Name Description 1 LOAD Sense amplifier input. High impedance input with Zener diode protection. Add an external protection resistor in series with LOAD if VSENSE exceeds the range of -600mV to +5V. 2 NC No connect. This pin must be left floating for proper operation. 3 IN Sense amplifier input and supply. 4 GND Supply return. 5 OUT Output with a nominal output resistance of 16.5kΩ. Preservation of accuracy may require an external buffer amplifier to prevent excessive loading. R SENSE + VSENSE - IN LOAD

Supertex inc. does not recommend the use of its products in life support applications, and will not knowingly sell them for use in such appl ications unless it receives an adequate “product liability indemnification insurance agreement.” Supertex inc. does not assume responsibility for use of devices described, and limits its liability to the replacement of the devices determined defective due to workmanship. No responsibility is assumed for possible omissions and inaccuracies. Circuitry and specifications ©2008 All rights reserved. Unauthorized use or reproduction is prohibited .

1235 Bordeaux Drive, Sunnyvale, CA 94089

Tel: 408-222-8888 www.supertex.com HV7801 (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to http://www.supertex.com/packaging.html.) Doc.# DSFP-HV7801 A120308 5-Lead SOT-23 Package Outline (K1) 2.90x1.60mm body, 1.45mm height (max), 0.95mm pitch Symbol A A1 A2 b D E E1 e e1 L L1 L2 θ θ1 Dimension (mm) 0.95 BSC 1.90 BSC 0.30 0.60 REF 0.25 BSC 0O 5O JEDEC Registration MO-178, Variation AA, Issue C, Feb. 2000. * This dimension is not specified in the original JEDEC drawing. The value listed is for reference only. Drawings not to scale. Supertex Doc. #: DSPD-5SOT23K1, Version NR110308. D Seating Plane Gauge Plane L Top View Side View View A - A View B View B θ E1 E A A2 A A Seating Plane e b Note 1 (Index Area D/2 x E1/2) Note: A Pin 1 identifier must be located in the index area indicated. The Pin 1 identifier can be: a molded mark/identifier; an embedded metal marker; or a printed indicator.