常見的靜電放電輸出輸入級電路

一般常見的靜電放電輸出輸入級電路如圖 5.1 所示，輸入級與輸出級的 PAD 連接拉 降與拉升元件，通常直接使用寄生於靜電放電輸出輸入級 NMOS 與 PMOS 中的 N-type 二極體與 P-type 二極體，也可以直接使用二極體，電壓鉗制元件則擺放在電源線與接地 線之間，正負極性的脈衝電流進入積體電路後的理想電流路徑如下:

Internal

Protection Input stage Output buffer Vdd-Vss

Protection

c. PD mode - 正極性脈衝電流由輸出輸入接腳對電源接腳測試

正極性的脈衝電流經由輸入或輸出端 PAD 進入積體電路後以順向偏壓的方式通過 拉升元件(寄生 P-type 二極體)將電流導到電源線，電流路徑如圖 5.3 實線所示（箭頭方 向為電洞流方向）。

d. ND mode - 負極性脈衝電流由輸出輸入接腳對電源接腳測試

負極性的脈衝電流經由輸入或輸出端 PAD 進入積體電路後以順向偏壓的方式通過 拉降元件(寄生 N-type 二極體)將電流導到接地線，電壓鉗制元件跨接於電源線與接地線 之間，電流拉降接地線電位使壓鉗制元件的基極與汲極的電位差增加，當此一電位差到 達電壓鉗制元件內寄生電晶體的啟始電壓時(元件崩潰電壓或是熱電子效應產生足夠的 基板電流)寄生電晶體導通將電流排放至電源線，可避免電流經由內部電路的閘極或是 經由接地線進入內部電路造成損害，電流路徑如圖 5.3 虛線所示（箭頭方向為電子流方 向）。

圖 5.2 PS mode 與 NS mode 的理想電流路徑。

Protection Input stage Output buffer Vdd-Vss

Protection

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

Protection Input stage Output buffer Vdd-Vss

Protection

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

Protection Input stage Output buffer

Internal

Protection Input stage Output buffer Vdd-Vss

Protection

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

Protection Input stage Output buffer Vdd-Vss

Protection

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

Output Protection Input

Protection Input stage Output buffer Vdd-Vss

Protection

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

Protection Input stage Output buffer Vdd-Vss

Protection

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

Protection Input stage Output buffer

Internal

Protection Input stage Output buffer Vdd-Vss

Protection

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

Protection Input stage Output buffer

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

Protection Input stage Output buffer Vdd-Vss

Protection

+ Pulse

- Pulse

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Pickup of HV-PMOS )

P- type( Drain of HV-PMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

N- type( Drain of HV-NMOS )

P- type( Pickup of HV-NMOS )

Protection Input stage Output buffer

Internal

Protection Input stage Output buffer

Internal

Protection Input stage Output buffer

Output

Protection Input stage Output buffer Vdd-Vss

Protection