– – E T E L OBSO HV421 High Voltage 1 REN Ring Generator Ordering Information Package Options Device 8-Lead SO HV421 HV421LG General Description Features 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 VPP pin. The DC-DC converter frequency of the HV421 is set by an external resistor connected between RSW and VDD. 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 RRING and VDD. 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 11 Pin Configuration Absolute Maximum Ratings* Supply Voltage, VDD -0.5V to +10V Output Voltage, Vcs -0.5V to +120V Operating Temperature Range Storage Temperature Range SO-8 Power Dissipation 0°C to +85°C -65°C to +150°C 400mW ςΑ Note: *All voltages are referenced to GND. VDD 1 8 Rring RSW 2 7 Gate VPP 3 6 Gate Lx 4 5 GND Top View SO-8 11-1 HV421 Electrical Characteristics DC Characteristics Symbol RDS(ON) (VDD=5.0V, RRING=30MΩ, RSW=1.3MΩ, LX=330µH, TA=25°C) Parameter On-resistance of switching transistor IDDQ Quiescent VDD supply current IDD Input current going into the VDD pin IIN Input current including inductor current VPP Min Typ Max Units 3.5 5 Ω I=100mA 50 nA RSW=Low 300 µA VIN=5.0V. See Figure 1. 220 mA VIN=5.0V. See Figure 1. V VIN=5.0V. See Figure 1. Hz VIN=5.0V. See Figure 1. 170 Output voltage on VPP 65 68 FRING Ring frequency 20 25 DRING Ringing frequency duty cycle 50 % fsw Switching transistor frequency 35 KHz Dsw Switching transistor duty cycle 88 % 30 Conditions VIN=5.0V. See Figure 1. Recommended Operating Conditions Symbol VDD TA Parameter Supply voltage Operating temperature Min Typ Max Units 4.75 9.5 V 0 85 °C Max Units – E T E L O S Enable/Disable Table B O – Symbol Parameter Min Typ EN-L Logic input low voltage 0 0.5 V EN-H Logic input high voltage VDD-0.5 VDD V 11-2 Conditions Conditions HV421 Block Diagram – E T E L O S B O – Lx VPP VDD RSW DC-DC Converter Gate RRING Ring Frequency Level Translator Gate GND Typical Application ON = 4.75V OFF = 0V 0.01µF 30M 11 Q1 D1 330µH VIN 4.75V 160mA 1 VDD RRING 8 D2 2 RSW Gate 7 Q2 3 VPP Gate 6 Lx GND 1.3M 2.2K Q3 2.2K 1N4148 4 6.8K 5 8.0µF D3 Load HV421LG 1.0µF Q1, Q3 = Supertex VN2110K1 Q2, Q4 = Supertex VP2110K1 D1–D4 = 5.1V Zener diode VOUT = ±60V Freq = 25Hz 0.01µF Figure 1: 1 REN Ring Generator 11-3 D4 Q4 HV421 Application Description Level translation of the ringing frequency The Supertex HV421LG is a high voltage 1 REN ring generator. 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. 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 VPP voltage. An inverted and a noninverted output are generated (gate and gate bar). Enable/Disable function DC-DC converter The DC-DC converter consists of a 330µH 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 1.0µF capacitor when the switch is in the off state. A high voltage DC will develop at VPP which is internally connected to the level translator. The HV421 can be enabled by connecting the 1.3MΩ and 30MΩ resistors to the same potential as VDD and disabled by connecting them to ground. External source follower buffer stage – E T E L O S B O – 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 8.0µF capacitor is used to simulate 1 North American REN (ringer equivalent number). The main specifications for the Supertex source follower transistors are listed below. Device Type Breakdown Voltage, BVDSS Gate Threshold Voltage, VGS(th) On-Resistance, RDS(ON) Package Options VN2110 N-Channel 100V 0.8V to 2.4V 6.0Ω at VGS=5V TO-92, SOT-23 VP2110 P-Channel -100V -1.5V to -3.5V 11Ω at VGS=-5V TO-92, SOT-23 11-4 HV430 Advanced Information High-Voltage Ring Generator Ordering Information Operating Voltage Package Options VPP1 - VNN1 SOW-20 325V HV430WG Features General Description 100VRMS ring signal 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 implemented 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. 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 PGATE 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 Nin will turn on the external N-channel MOSFET. Lockout circuitry prevents the N and P switches from turning on simultaneously. Applications High voltage ring generator 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 Nin 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. Set-top/Street box ring generator Absolute Maximum Ratings 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 Storage temperature Power dissipation +7.5V -65°C to +150°C 800mW 11-5 11