Output driving circuit and transistor output circuit

• US 8,823,425 B2
• Filed: 08/07/2012
• Issued: 09/02/2014
• Est. Priority Date: 08/09/2011
• Status: Expired due to Fees

• Current Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Heo, Chang Jae
• Primary Examiner(s): NGUYEN, LONG T
• Application Number:
  US13/569,094
• Publication Number:
  US 20130038356A1
• Time in Patent Office: 756 Days
• Field of Search: 327/108, 327/112, 327/333, 327/389, 327/391, 326/26, 326/27, 326/68, 326 80- 83
• US Class Current: 327/112
• CPC Class Codes: H03K 17/08122 in field-effect transistor switches
• CPC Class Codes: H03K 3/356104 using complementary field-effect transistors H03K3/35625 takes precedence

Abstract

Disclosed herein are an output driving circuit and a transistor output circuit. The output driving circuit includes: a reference voltage generating unit generating a reference voltage; a level shift unit including a transistor latch and turning off a first transistor of a driving circuit or driving the first transistor; a driving circuit unit including the first transistor that is driven to apply power to a gate of an output transistor and a second transistor that is driven complementarily to the first transistor to lower a gate voltage of the output transistor and drive the output transistor; and an withstand voltage protecting unit that is driven by receiving a reference voltage and includes a first withstand voltage protecting unit for protecting transistors of the transistor latch and the first transistor for stable operations thereof and a second withstand voltage protecting unit for protecting the output transistor for a stable operation thereof.

Claims

1. An output driving circuit, comprising:

a reference voltage generating unit for generating a reference voltage having a predetermined voltage difference with respect to a high voltage power source;

a level shift unit including a latch and turning off a first transistor of a driving circuit unit by applying the high voltage power source to the first transistor according to an input signal of an input terminal or driving the first transistor by lowering a gate voltage of the first transistor according to the input signal of the input terminal;

the driving circuit unit including the first transistor that is driven according to a control of the level shift unit to apply the high voltage power source to a gate of an output transistor that is driven by driving of the driving circuit unit and a second transistor that is driven complementarily to the first transistor to lower a gate voltage of the output transistor and drive the output transistor; and

an withstand voltage protecting unit that is driven by receiving the reference voltage generated from the reference voltage generating unit and includes a first withstand voltage protecting unit for protecting transistors of the latch and the first transistor for stable operations thereof and a second withstand voltage protecting unit for protecting the output transistor for a stable operation thereof.

2. The output driving circuit according to claim 1, wherein the level shift unit includes:

a first inverter for inverting the input signal of the input terminal;

the latch including third and fourth transistors that are P-channel transistors each having a source electrode connected to the high voltage power source, a gate of the fourth transistor being connected to a drain of the third transistor and a gate of the third transistor being connected to a drain of the fourth transistor and a gate of the first transistor;

an N-channel fifth transistor that is driven according to the input signal of the input terminal and lowers a gate voltage of the fourth transistor; and

an N-channel sixth transistor that is driven according to an input corresponding to an inverting output of the first inverter and drives the first transistor by lowering the gate voltage of the first transistor.

3. The output driving circuit according to claim 2, wherein the driving circuit unit includes:

a second inverter for receiving and inverting an output of the first inverter;

the first transistor that is driven by a gate voltage'"'"'s lowering according to driving of the sixth transistor and turns off the output transistor by applying the high voltage power source connected to a source electrode to the gate of the output transistor; and

the second transistor that is driven complementarily to the first transistor by receiving an output of the second inverter and pulls the gate voltage of the output transistor down to a low voltage power source to lower the gate voltage of the output transistor,

wherein the first transistor is a P-channel transistor and wherein the second transistor is an N-channel output transistor.

4. The output driving circuit according to claim 2, wherein the first withstand voltage protecting unit includes:

a P-channel seventh transistor that is driven by receiving the reference voltage and pulls a gate voltage of the fourth transistor connected to a source electrode down to the fifth transistor connected to a drain electrode to lower the gate voltage of the fourth transistor; and

a P-channel eighth transistor that is driven by receiving the reference voltage and pulls gate voltages of the first and third transistors connected to a source electrode down to the sixth transistor connected to a drain electrode to lower the gate voltages of the first and third transistors, and

wherein the second withstand voltage protecting unit includes a P-channel ninth transistor that is driven by receiving the reference voltage and pulls the gate voltage of the output transistor connected to a source electrode down to the second transistor connected to a drain electrode to lower the gate voltage of the output transistor.

5. The output driving circuit according to claim 1, wherein the reference voltage generating unit includes a Zener diode connected to the high voltage power source.

6. The output driving circuit according to claim 1, wherein the reference voltage generating unit includes a plurality of P-channel MOSFETs that are connected in series to the high voltage power source.

7. The output driving circuit according to claim 1, wherein the reference voltage generating unit includes a plurality of N-channel MOSFETs that are connected in series to the high voltage power source.

8. The output driving circuit according to claim 1, wherein the output transistor is a P-channel MOSFET or a P-channel LDMOS transistor that is driven by driving of the second transistor of the driving circuit unit to output high voltage power.

9. The output driving circuit according to claim 2, wherein the output transistor is a P-channel MOSFET or a P-channel LDMOS transistor that is driven by driving of the second transistor of the driving circuit unit to output high voltage power.

10. The output driving circuit according to claim 3, wherein the output transistor is a P-channel MOSFET or a P-channel LDMOS transistor that is driven by driving of the second transistor of the driving circuit unit to output high voltage power.

11. The output driving circuit according to claim 4, wherein the output transistor is a P-channel MOSFET or a P-channel LDMOS transistor that is driven by driving of the second transistor of the driving circuit unit to output high voltage power.

12. A transistor output circuit, comprising:

the output transistor according to claim 1 having a source electrode connected to the high voltage power source and outputting high voltage power through a drain electrode;

an N-channel output transistor that operates complementarily to the output transistor and pulls power from a drain electrode connected to the drain electrode of the output transistor down to a lower voltage power source connected to a source electrode; and

the output driving circuit according to claim 1, for driving each of the output transistor and the N-channel output transistors according to a complementary switching operation,

wherein the output transistor is a P-channel output transistor.

13. The transistor output circuit according to claim 12, wherein the level shift unit of the output driving circuit includes:

a first inverter for inverting the input signal of the input terminal;

the latch including third and fourth transistors that are P-channel transistors each having a source electrode connected to the high voltage power source, a gate of the fourth transistor being connected to a drain of the third transistor and a gate of the third transistor being connected to a drain of the fourth transistor and a gate of the first transistor;

an N-channel fifth transistor that is driven according to the input signal of the input terminal and lowers a gate voltage of the fourth transistor; and

an N-channel sixth transistor that is driven according to an input corresponding to an inverting output of the first inverter and drives the first transistor by lowering the gate voltage of the first transistor.

14. The transistor output circuit according to claim 13, wherein the driving circuit unit of the output driving circuit includes:

a second inverter for receiving and inverting an output of the first inverter;

the first transistor that is driven by a gate voltage'"'"'s lowering according to driving of the sixth transistor and turns off the output transistor by applying the high voltage power source connected to a source electrode to the gate of the output transistor; and

the second transistor that is driven complementarily to the first transistor by receiving an output of the second inverter and pulls the gate voltage of the output transistor down to a low voltage power source to lower the gate voltage of the output transistor,

wherein the first transistor is a P-channel transistor and wherein the second transistor is an N-channel output transistor.

15. The transistor output circuit according to claim 13, wherein the first withstand voltage protecting unit of the output driving circuit includes:

a P-channel seventh transistor that is driven by receiving the reference voltage and pulls a gate voltage of the fourth transistor connected to a source electrode down to the fifth transistor connected to a drain electrode to lower the gate voltage of the fourth transistor; and

a P-channel eighth transistor that is driven by receiving the reference voltage and pulls gate voltages of the first and third transistors connected to a source electrode down to the sixth transistor connected to a drain electrode to lower the gate voltages of the first and third transistors, and

wherein the second withstand voltage protecting unit includes a P-channel ninth transistor that is driven by receiving the reference voltage and pulls the gate voltage of the output transistor connected to a source electrode down to the second transistor connected to a drain electrode to lower the gate voltage of the output transistor.

16. The transistor output circuit according to claim 12, wherein the P-channel output transistor is driven by driving of the second transistor, and the N-channel output transistor is driven according to a complementary input to the input signal of the input terminal for driving the second transistor.