HV421

HV421 SUTEX | Alldatasheet

Document overview

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Technical content

Features

Processed with HVCMOS ® technology 4.75V to 9.5V operating supply voltage DC to AC conversion

1 REN load capacity

Adjustable ring frequency from 15Hz to 60Hz Adjustable converter frequency Enable/Disable function

Ordering Information

The Supertex HV421 is a high voltage ring generator designed to drive 1 North American REN (ringer equivalent number) from a 5V source. The HV421 has an internal DC-DC converter which converts the 5V DC supply to a nominal 68V DC connected to the V PP pin. The DC-DC converter frequency of the HV421 is set by an external resistor connected between R SW and V DD. The ringing signal is generated by a high voltage H-bridge which produces two square waves which are 180 degrees from each other. The ringing frequency of the H-bridge is set by an external resistor connected between R RING and VDD. Pin Configuration ςΑ Package Options Device 8-Lead SO HV421 HV421LG Top View VDD Rring RSW Gate VPP Gate Lx GND SO-8 – OBSOLETE –

Symbol Parameter Min Typ Max Units Conditions RDS(ON) On-resistance of switching transistor 3.5 5 Ω I=100mA IDDQ Quiescent VDD supply current 50 nA R SW=Low IDD Input current going into the V DD pin 300 µAV IN=5.0V. See Figure 1. IIN Input current including inductor current 170 220 mA V IN=5.0V. See Figure 1. VPP Output voltage on V PP 65 68 V V IN=5.0V. See Figure 1. FRING Ring frequency 20 25 30 Hz V IN=5.0V. See Figure 1. DRING Ringing frequency duty cycle 50 % fsw Switching transistor frequency 35 KHz V IN=5.0V. See Figure 1. Dsw Switching transistor duty cycle 88 %

Electrical Characteristics

DC Characteristics (VDD=5.0V, RRING=30MΩ, RSW=1.3MΩ, LX=330µH, TA=25°C) Symbol Parameter Min Typ Max Units Conditions VDD Supply voltage 4.75 9.5 V TA Operating temperature 0 85 °C Recommended Operating Conditions Symbol Parameter Min Typ Max Units Conditions EN-L Logic input low voltage 0 0.5 V EN-H Logic input high voltage V DD-0.5 V DD V Enable/Disable Table HV421 – OBSOLETE –

1.3M 0.01µF VIN HV421LG 330µH 1N4148 VDD RSW VPP Lx RRING Gate Gate GND ON = 4.75V OFF = 0V Q1 Q3 8.0µF Load Q41.0µF 6.8K 4.75V 160mA 0.01µF 2.2K 2.2K Q1, Q3 = Supertex VN2110K1 Q2, Q4 = Supertex VP2110K1 D1–D4 = 5.1V Zener diode VOUT = ±60V Freq = 25Hz Figure 1: 1 REN Ring Generator HV421 – OBSOLETE –

Device Type Voltage, BV DSS Voltage, VGS(th) On-Resistance, RDS(ON) Package Options VN2110 N-Channel 100V 0.8V to 2.4V 6.0 Ω at VGS=5V TO-92, SOT-23 VP2110 P-Channel -100V -1.5V to -3.5V 11 Ω at VGS=-5V TO-92, SOT-23 Application Description The Supertex HV421LG is a high voltage 1 REN ring genera- tor. A typical application circuit is shown in Figure 1. There are four basic parts to the circuit; the DC-DC converter, level translation of the ringing frequency, enable/disable function, and an external source follower buffer stage. Enable/Disable function The HV421 can be enabled by connecting the 1.3M Ω and 30MΩ resistors to the same potential as VDD and disabled by connecting them to ground. DC-DC converter The DC-DC converter consists of a 330 µH inductor, 1N4148 diode, 1.0µF capacitor and 1.3MΩ resistor. The 1.3MΩ resistor sets the DC-DC converter frequency. Energy is stored in the 330µH inductor when the switching transistor is turned on and is released into the 1.0 µF capacitor when the switch is in the off state. A high voltage DC will develop at V PP which is internally connected to the level translator. Level translation of the ringing frequency The ringing frequency is set by a 30MΩ resistor. A low voltage square wave is generated with a nominal frequency of 25Hz. Lower ringing frequencies can be obtained by using resistors greater than 30MΩ. The signal is then level translated to swing from 0V to the V PP voltage. An inverted and a noninverted output are generated (gate and gate bar). External source follower buffer stage The gate and gate bar are connected to an external source follower stage. Supertex transistors VP2110K1 and VN2110K1 are used for the buffering. Zener diodes clamps across the gates are recommended as a precaution but not required. The voltage seen by the load is ±60V. A 6.8KΩ resistor in series with an 8.0 µF capacitor is used to simulate 1 North American REN (ringer equivalent number). The main specifi- cations for the Supertex source follower transistors are listed below. HV421 – OBSOLETE –

VPP1 - VNN1, power supply voltage +340V VPP1, positive high voltage supply +220V VPP2, positive gate voltage supply +220V VNN1, negative high voltage supply -220V VNN2, negative gate voltage supply -220V VDD, logic supply +7.5V Storage temperature -65 °C to +150°C Power dissipation 800mW Operating Voltage Package Options VPP1 - VNN1 SOW-20 325V HV430WG General Description The Supertex HV430 is a high voltage PWM ring generator integrated circuit. The high voltage outputs, Pgate and Ngate, are used to drive the gates of external high voltage P-channel, TP2640, and N-channel, TN2640, MOSFETs in a push-pull configuration. Pulse by pulse over current protection are imple- mented on both the P-channel and N-channel MOSFETs. The RESET inputs functions as a power-on reset and as a low voltage lockout, allowing for hot-swapping capabilities. The FAULT output indicates over-current and low voltage lockout conditions. It is active-low and open-drain to allow wire OR’ing of multiple drivers. P GATE and NGATE are controlled independently by logic inputs Pin and Nin when the mode pin is at logic high. A logic high on Pin will turn on the external P-channel MOSFET. Similarly, a logic high on N in will turn on the external N-channel MOSFET. Lockout circuitry prevents the N and P switches from turning on simulta- neously. For applications where a single control input is desired, the mode pin should be connected to Gnd. The PWM control signal is then input to the N in pin. A user-adjustable deadband in the control logic assures break-before-make on the outputs, thus avoiding cross conduction on the high voltage output during switching. A logic high on Nin will turn the external P-Channel MOSFET on and the N-Channel off, and vice versa. The IC can be powered down by applying a logic low on the Enable pin, placing both external MOSFETs in the off state. High-Voltage Ring Generator Output over current protection 5.0V CMOS logic control Logic enable/disable to save power Fault output for over-current and low voltage lockout conditions Adjustable deadband in single-control mode Power-on reset for hot-swap protection Low voltage lockout

Applications

High voltage ring generator Set-top/Street box ring generator Advanced Information